Rest-Based Training - Metabolic Effect...
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Rest-Based Training A New System and Psychology for Safe and Effective Exercise Jade Teta ND, CSCS Safety and results. These are the primary charge of every fitness professional. But it is not easy. After all, the two ideas are diametrically opposed. Too much attention to one often leads to problems with the other. Fitness professionals require tools that work, are safe and can be adapted to each and every individual. High intensity unconventional workouts are surging in popularity and hold real promise in delivering results. But how does a trainer or group exercise instructor use these tools while keeping things safe and manageable for all fitness levels and physical abilities? A new training tool called rest-based training (RBT) may provide a solution. RBT is a system that makes rest, not work, the primary goal of the workout. It allows participants to take rest when needed and for as long as necessary. Rest actually becomes a tool for increasing intensity, because exercisers can use it strategically to work harder than they could without rest. It also provides a buffer against overexertion making even high-intensity workouts safe. In RBT, the protocol adapts to the individual rather than forcing a person to adjust to it. The physiological link between rest, intensity and results Work and rest are often viewed as opposites. In reality, they are closely linked and dependent on one another. For a real world example, consider a sprinter running a 100-meter race. If at the completion of the race he or she was told to immediately run the race again, could they muster the same degree of intensity? Intense exertion is the major determinant of physical adaptation and rest is the chief driver of intensity. Without rest, exercise must be naturally regulated with pacing strategies. This is a key insight because aerobic exercise modalities by their very nature do not employ rest. With aerobic exercise, the only options to increase intensity are going farther or exercising for longer. This may not be the most efficient way to drive results. A 1997 meta-analysis by Miller et al. (1997) analyzed 400 plus aerobic exercise studies spanning over 25 years. The conclusion of the research was that aerobic exercise provides an insignificant weight loss advantage over diet by itself. Melanson, et. al (2009) more recently showed little metabolic stimulation from moderate intensity aerobic exercise beyond the calories burned during activity. At the same time, researchers have determined higher intensity exercise like weight training and interval exercise burns significantly more calories than once thought and can provide a substantial metabolic advantage. Anaerobic contributions to energy use can be underestimated by 70% for weight training and 95% for interval exercise (Scott 2005; 2009). The metabolic advantage can also result in a significant “after-burn” that can last 16 hours in women and 48 hours in men. (Schuenke 2002; Osterberg 2000). Interval training, boot camps, metabolic conditioning and other more anaerobic programs are surging in popularity. They also seem to deliver on the promise of results. When compared head to head against traditional aerobics some research shows substantial benefit. Trapp et. al. (2008) looked at a 20-minute anaerobic interval program compared to 40-minutes of aerobics. The programs were conducted 3 times each week
Transcript of Rest-Based Training - Metabolic Effect...
Rest-Based Training A New System and Psychology for Safe and Effective Exercise Jade Teta ND, CSCS
Safety and results. These are the primary charge of every fitness professional. But it is not easy. After all, the two ideas are diametrically opposed. Too much attention to one often leads to problems with the other.
Fitness professionals require tools that work, are safe and can be adapted to each and every individual. High intensity unconventional workouts are surging in popularity and hold real promise in delivering results. But how does a trainer or group exercise instructor use these tools while keeping things safe and manageable for all fitness levels and physical abilities?
A new training tool called rest-based training (RBT) may provide a solution. RBT is a system that makes rest, not work, the primary goal of the workout. It allows participants to take rest when needed and for as long as necessary. Rest actually becomes a tool for increasing intensity, because exercisers can use it strategically to work harder than they could without rest. It also provides a buffer against overexertion making even high-intensity workouts safe. In RBT, the protocol adapts to the individual rather than forcing a person to adjust to it. The physiological link between rest, intensity and results
Work and rest are often viewed as opposites. In reality, they are closely linked and dependent on one another. For a real world example, consider a sprinter running a 100-meter race. If at the completion of the race he or she was told to immediately run the race again, could they muster the same degree of intensity?
Intense exertion is the major determinant of physical adaptation and rest is the chief driver of intensity. Without rest, exercise must be naturally regulated with pacing strategies. This is a key insight because aerobic exercise modalities by their very nature do not employ rest. With aerobic exercise, the only options to increase intensity are going farther or exercising for longer. This may not be the most efficient way to drive results.
A 1997 meta-analysis by Miller et al. (1997) analyzed 400 plus aerobic exercise studies spanning over 25 years. The conclusion of the research was that aerobic exercise provides an insignificant weight loss advantage over diet by itself. Melanson, et. al (2009) more recently showed little metabolic stimulation from moderate intensity aerobic exercise beyond the calories burned during activity.
At the same time, researchers have determined higher intensity exercise like weight training and interval exercise burns significantly more calories than once thought and can provide a substantial metabolic advantage. Anaerobic contributions to energy use can be underestimated by 70% for weight training and 95% for interval exercise (Scott 2005; 2009). The metabolic advantage can also result in a significant “after-burn” that can last 16 hours in women and 48 hours in men. (Schuenke 2002; Osterberg 2000).
Interval training, boot camps, metabolic conditioning and other more anaerobic programs are surging in popularity. They also seem to deliver on the promise of results. When compared head to head against traditional aerobics some research shows substantial benefit. Trapp et. al. (2008) looked at a 20-minute anaerobic interval program compared to 40-minutes of aerobics. The programs were conducted 3 times each week
for 15 weeks. At the end of the study the anaerobic group lost approximately 5 pounds of fat while the aerobic group showed a non-significant trend towards fat gain.
The trick is to adopt some of the tools and techniques of higher intensity exercise protocols, while keeping the workouts safe and scalable for all fitness levels. This is not an easy task. The average exerciser is not always equipped physiologically or psychologically to push themselves to the exertion levels required to generate the results they seek. Rest-based training solves this issue.
Exercise motivation and self-regulation Rest-based training draws inspiration from the school of psychology and its self-determination theory (SDT). Self-determination theory posits those who are given autonomy over change are far more likely to develop and maintain innate motivation. (Deci 2004; Markland 2005; Ryan 2000). This is in contrast to those who are coerced into change. Rest-based training brings this concept to exercise. By giving the exerciser control over when to rest and for how long, work volume can increase while safety is maintained.
Many current exercise trends work against the principles of self-determination theory. The keep-up-militancy of boot camps and the competitive approach of some metabolic conditioning programs are examples. These approaches, while effective for some, may be counterproductive for significant segments of the population.
RBT flips these models around and gives complete control of the workout over to the exerciser. By doing so, it creates self-motivation and ownership over exercise so that participants not only work harder, but also become better aware of their physiology and more engaged in their programs. RBT encourages participants to adjust work and rest ratios according to their individual needs. The wording used in this approach is “push until you can’t, rest until you can”.
Contrary to popular perception, exercisers given the ability to self-regulate exertion do not necessarily default to lower exercise intensities. A review by Ekkekakkis et al. (2009) highlights research showing exercisers instead work at greater intensities than predicted. This remains true so long as the intensity remains below the anaerobic threshold. This is the whole theory behind interval training, which employs rest to allow greater exertion. RBT takes this concept one step further by using rest coupled with control. This achieves the results of interval training while keeping the workout safe and appropriate for all fitness levels.
Self-regulation in exercise is a built in feature of movement management seen in animals. Animals naturally regulate exercise by using a burst-then-rest strategy (Ekkekakis 2009). This is likely an evolutionary adaptation allowing animals to maximize distances covered in a given time. It appears humans have the same ability to regulate intensity by employing rest (Edwards 2010). Rest-based training versus interval training
The main goal of interval training is to balance the work intensity of every interval using the help of rest. Implementing the shortest rest period possible for metabolic recovery helps accomplish this. The “metabolic recovery” has to do with the clearance of hydrogen ions, restoration of phosphocreatine, recycling of lactate, and
resetting of electrolyte gradients. Once this is accomplished, the physiology can perform at a high level once more. This reset point is likely different for everyone.
Definitive interval protocols present a challenge, for example 30s of work followed by 30s of rest. They are often too intense for the average exerciser and provide inadequate metabolic recovery. At best, this will cause pacing which compromises workout results, and at worst presents safety concerns.
According to RBT, individuals will self-regulate work and rest intervals to maximize intensity and ensure adequate recovery. Research shows this is indeed the case. In a study by Edwards et al. (2010), 11 well-trained runners were put through two trials. In the first trial, 1, 2, and 4 minutes of rest were given after 4 minutes of intense exertion. Researchers wanted to determine which resting protocol provided adequate metabolic reset for the physiology. They found 1 minute was too short, 4 minutes was too long and 2 minutes was just right. The experiment was then repeated. Only this time, the exercisers were instructed to rest as long as they felt was adequate and then resume the workout when they “felt” ready. Surprisingly, the average rest taken by the participants in the second experiment was 118 seconds, almost identical to the two minutes researchers previously determined was most beneficial from a physiological perspective. The researchers concluded, “The concept of self-pacing facilitates greater self-awareness of physical capabilities………and it is our contention that the combination of using ratings of perceived exertion to gauge interval effort and perceived readiness scales to gauge recovery may be a useful means of organizing interval training according to individual conditioning requirements.” Rest-based training principles There are four key components of RBT represented by the acronym R-E-S-T:
• R= Rest-based. Rest, not work is the goal of rest-based training. This automatically increases the quality of work done, and it makes exercise psychologically easier (Edwards 2010; Ekkekakis 2009; Lander 2010; Rose 2010; Williams 2008). When exercisers have permission to rest according to their needs, they voluntarily work harder without being consciously aware they are doing so.
• E= Extrinsic focus. Intrinsic sensations, such as breathlessness, burning and
other sensations, are inhibitors of exercise intensity (Duncan 2010; Williams 2008). Rest-based training incorporates techniques that focus exercisers on what they are doing (extrinsic factors) versus what they are feeling (intrinsic feelings). With this in mind, an RBT workout is often structured to be quick moving and psychologically motivating.
• S= Self-determined. RBT workouts are structured, but the exerciser has complete
autonomy over exertion and rest. They are taught to use their rest strategically to push harder than they could without it. Giving control to the exerciser increases workout quality (Edwards 2010.), improves exercise adherence (Deci 2004; Ekkekakis 2009; Markland 2005; Ryan 2000; Rose 2010; Williams 2008), makes
exercise psychologically easier (Lander 2010) and improves results overtime when compared to more definitive exercise prescriptions (Mann 2010).
• T= Time conscious. Time and intensity are linked. So, harder workouts must be
shorter by necessity. RBT workouts usually last from 20 to 40 minutes and incorporate start and stop working and resting segments according to individual needs.
RBT in practice In order to help the novice exerciser tap into their inherent ability to self-regulate exercise, RBT teaches a 1 to 4 scale. This scale works as both an exertion score and a readiness rating. It works to help the exerciser and/or their trainer recognize more clearly when they should rest, and when they may want to resume training. Research has shown this to be a reliable tool in maximizing work and rest to generate optimal intensities for results (Edwards 2010). It also keeps the workout safe and manageable. RBT exertion scale:
1- Exerciser is at rest 2- Exerciser is exercising but can still talk, there is no burning in muscles and/or the
weight is light. 3- Exerciser can no longer talk, there is burning in the muscle and/or the weight is
getting heavy. 4- Exerciser must rest and recover.
RBT readiness scale:
1- Ready for full exertion. 2- Ready to attempt full exertion. 3- Unable to attempt full exertion. 4- No exertion is possible
The goal of the workout is to reach a 4 on the RBT exertion scale repeatedly. Rest is
then taken until the exerciser reaches a 2 on the RBT readiness scale. In time, the scales are no longer required as the participant learns to quickly hone in on their self-regulating abilities. A sample RBT workout Here is a simple rest-based training workout that illustrates the concept. This can be done with a group of clients or in a one-on-one personal training setting.
• Choose 3 full body exercises using a 10 to 15 rep max. • Complete 8 reps of each exercise in circuit fashion. • Instruct trainee/trainees to work until rest is required, reaching a 4 on the RBT
exertion scale. • Coach them to rest as long as required reaching a 2 on the RBT readiness scale • Direct exercisers to resume the workout right where they left off. • Have them continue this way starting and stopping according to their own needs.
The phrasing to use is “push until you can’t, rest until you can” • Use a stopwatch a time the circuit for 10 minutes. Remember, there is no
structured rest. The trainee/trainees take rest according to their own needs. • After 10 minutes choose another three exercises and have them go for another 10
minutes. • Repeat a third time with another 3 exercises for a total of 30 minutes. During the workout, some exercisers will use lots of short rests while others will
prefer less frequent and longer rests. The trainers job is to cue, coach and motivate the client by reminding them they are in control.
Final thoughts
Trainers are taught systems and protocols and are expected to fit a diverse client base to a specific program. It can be hard to find the right fit. The choices range from the keep-up-militancy of boot camps, the don’t-be-beat competitive approach or the treat-with-kid-gloves mindset. RBT teaches the exerciser to instead fit the program to their unique fitness level and physical abilities. This provides trainers with a much needed tool. The focus on rest and autonomy finds common ground between safety and results. It is a science-based approach drawn from the best of psychology and conditioning research and holds promise to bridge the gap between safe and effective workouts.
eferen R
ces:
• ding Deci, et al. 2004. Self‐determination theory and basic need satisfaction: Understanhuman development in positive psychology. Ricerche di Psichologia, 27, 17‐34.
• Duncan, et al. 2010. Exercise motivation: a cross‐sectional analysis examining its nal of relationships with frequency, intensity and duration of exercise. International Jour
Behavioral Nutrition and Physical Activity, 7, 7. • Edwards et al. 2010. Self‐pacing in interval training a teleoanticipatory approach.
Psychophysiology, Published ahead of print. • Ekkekakis, et al. 2009. Let Them Roam Free? Physiological and Psychological Evidence for
the Potential of Self‐Selected Exercise Intensity in Public Health. Sports Medicine, 39(10), 857‐888.
• Lander, et al. 2003. Self‐paced exercise is less physically challenging then forced constant ish paced exercise of the same intensity: influence of complex central metabolic control. Brit
Journal of Sports Medicine, 43, 789‐795. • Mann, et al. 2010. The effect of autoregulatory progressive resistance exercise vs. linear
periodization on strength improvement in college athletes. Journal of Strength and Conditioning Research, 24(7), 1718‐1723.
• Markland, et al. 2005. Motivational interviewing and self‐determination theory. Journal of Social and Clinical Psychology, 24, 811–831.
• 4‐Melanson, et al. 2009. Exercise improves fat metabolism in muscle but does not increase 2hr fat oxidation. Exercise and Sport Sciences Reviews, 37(2),93‐101.
• g diet,
Miller, et al. 1997. A meta analysis of the past 25 years of weight loss research usinexercise or diet plus exercise intervention. International Journal of Obesity, 21, 941‐947.
• Osterberg, et al. 2000. Effect of acute resistance exercise on post‐exercise oxygen consumption and resting metabolic rate in young women. International Journal of Sport Nutrition and Exercise Metabolism, 10(1), 71‐81.
• Rose, et al. 2010. Exercise experience influences affective and motivational outcomes of prescribed and self‐selected intensity exercise. Scandanavian Journal of Medicine and Science in Sports, Published ahead of print.
• Ryan, et al. 2000. Self‐determination theory and the facilitation of intrinsic motivation, social development, and well‐being. American Psychologist, 55, 68‐78.
• Schuenke, et al. 2002. Effect of an acute period of resistance exercise on excess post‐exercise oxygen consumption: Implications for body mass management European Journal of Applied
Physiology, 86, 411‐417. • e. Journal Scott, et al. 2005. Misconceptions about aerobic and anaerobic energy expenditur
of the International Society of Sports Nutrition, 2, 32‐37. • Scott et al. 2005. Contributions of Anaerobic Energy Expenditure to Whole‐body
Thermogenesis. Nutrition and Metabolism, 2, 14. • Scott, et al. 2009. Energy expenditure before during and after the bench press. Journal of
Strength and Conditioning Research, 23(2), 611‐618. • Trapp, et al. The effects of high‐intensity intermittent exercise training on fat loss and fasting
insulin levels of young women International Journal of Obesity. 2008;32:684‐691 • Treuth, et al. 1996. Effects of exercise intensity on 24‐h energy expenditure and substrate
oxidation. Medicine and Science in Sport and Exercise, 28:1138‐1143 • Williams, et al. 2008 Exercise, affect, and adherence: an integrated model and a case for self‐
selected exercise. Journal of Sport and Exercise Psychology, 30, 471‐496. Learning Objectives:
1) Explain the connection between rest, exercise intensity and exercise safety. 2) Discuss how the principles of self-determination theory can elevate workout
intensity and results. 3) Define the key components of rest-based training (RBT) and how they are applied
in practice. CEC questions:
1) What is the major insight RBT borrows from self-determination theory? a. Coerced exercise frequently leads to increased workout adherence. b. Self-regulated exercise usually results in reduced exercise effort. c. Providing workout autonomy produces decreased motivation to exercise. d. Giving control to the exerciser generates greater exercise motivation.
Answer= d. 2) How does RBT differ from interval training?
a. RBT makes rest, not work, the goal of the workout. b. RBT allows exercisers to control the length of work intervals, but limits
rest to a set amount of time. c. RBT defines a structured work phase and a finite rest time. d. There is no difference between interval training and RBT.
Answer= a. 3) How many rests are taken in an RBT workout and how long are they taken for?
a. Rest can be taken whenever it is needed, but must be limited to a set time. b. Rest is taken as often as needed, and it can last as long as is required. c. The number and timing of rest intervals are set at the start of the workout. d. Rest can be taken when needed, but the rest intervals last exactly 2
minutes.
Answer= b. 4) What are the 4 key components of rest-based training (RBT) designated by the
acronym R-E-S-T? a. Rest-based, Enhanced motivation, Self-selected, Time conscious. b. Rest-regulated, Easy pacing, Self-determined, Time dominant c. Rest-based, Extrinsic motivation, Self-determined, Time conscious. d. Rest-based, Enhanced motivation, Self-regulated, Time sensitive.
Answer= c. 5) What two scales are used in RBT to guide the client in self-regulation of their
work and rest ratios? a. An exertion scale and a readiness scale. b. The Borg scale and a 1-4 readiness scale c. A 1-10 scale of readiness and exertion d. There are no scales used. The work and rest ratios are guided by the
intrinsic sensations of the exerciser. Answer= a.
Rest‐Based Training A new system and psychology for exercise
Jade Teta ND, CSCS and Keoni Teta ND, LAc, CSCS Recent research has raised questions about how useful aerobic exercise can be in combating obesity. In contrast, more intense exercise, such as weight lifting and intermittent burst type activity, provides unique fat loss advantages. Despite this new understanding, physicians remain reluctant to embrace intense exercise modalities due to concerns over safety and applicability. We have developed a novel fitness method we call rest‐based training (RBT) that allows all fitness levels to ngage in and benefit from high intensity exercise protocols in a safe and scalable ay.
ew The science of aerobics, anaerobic exercise and weight loss In 1997 Miller et. al. published a meta‐analysis on the impact of aerobic exercise to combat weight gain (1). This research looked at close to 500 studies over a period of 25 years. The results showed aerobic exercise provided only about a 2‐pound weight loss advantage over diet alone. A more recent review by Melanson et. al. showed mostly aerobic exercise provided no metabolic advantage beyond calories burned during the activity (2). In contrast, Dr. Chris Scott at the University of Southern Main has shown anaerobic energy use can be underestimated by 70% for weight training and 95% for interval exercise (7‐9). Anaerobic exercise also elevates fat and calorie use after exercise has ended. This “after‐burn” can last 16 hours in women and 48 hours in men mounting to many hundreds of calories burned at rest as a result of the workout a(4‐5). Trapp et. al. compared 20‐minutes anaerobic interval training to 40‐minutes of aerobic zone exercise (3). Each program was done 3 times per week for 15 weeks. At the end of the study the anaerobic group lost approximately 5 pounds of fat while the aerobic group surprisingly gained fat. Insulin and leptin were also positively impacted by the interval exercise but not the aerobic workout. Shifting from a work to a rest paradigm in exercise Rest and movement are often seen as opposites, but they are actually complementary and dependent on each other. Exercisers told to run as fast as possible for 10 minutes will necessarily regulate intensity to complete the task. If they were instead told to run as fast as possible for 10 seconds, the intensity could e dramatically elevated. True high intensity exercise is impossible to achieve bwithout rest. Quality rest leads to quality work and vice versa. High intensity interval training (HIIT) and intense weight lifting have always coupled work with rest. One issue with these workouts is the ridged structure. The
work to rest ratios “force” individuals of varying fitness levels to work at mandated levels. This works to lower intensity, inducing the same pacing effect seen in traditional aerobic exercise. These type workouts are often too intense for many and can create psychological resistance to participating. Restbased training (RBT) Rest‐based training (RBT) uses rest, autonomy and time manipulation to optimize intensity for all fitness levels. It combines the latest in exercise science and otivational psychology. Rest‐based training enjoys the same physiological benefits
ts. mof intense interval exercise and weight training but with key psychological benefi Rest‐based training differs in the application of rest. Where interval training and weight training have clearly defined work and rest ratios, RBT leaves the exerciser in charge of when to rest and for how long. The language employed in this type of raining is “push until you can’t, rest until you can.” This shift in paradigm acts as treverse psychology for exercisers. Motivational psychology of exercise is an important consideration regarding exercise consistency, frequency and intensity. The primary goal and purpose of interval training is to maximize work effort across all work bouts and employ the shortest recovery time possible to maximize the training stimulus. Contrary to popular belief, research has shown exercisers who have autonomy over their orkout parameters will often work harder and are able to self‐regulate to an ptimal work to rest ratio for their physiology (17‐19). wo Restbased training principles There are four key attributes in our RBT system. All are geared towards maximizing ork effort in a safe and scalable way. The key tenets of rest‐based exercise are epresentedwr by the acronym R‐E‐S‐T: Restbased. Pushing to the point of rest is actually the goal of a rest‐based workout. By putting the focus on rest, as opposed to work, RBT not only automatically increases the quality of work, but also makes exercise psychologically easier (17‐19, 1). When exercisers know they have permission to rest they may voluntarily work 2harder without even being consciously aware they are doing so. Interestingly, animal research shows intermittent exercise is inherent and may be an evolutionary adaptation to maximize distances covered per unit time (19). Animals naturally engage in sporadic work and rest ratios during movement and elf regulate exercise to optimize both performance and recovery. Research shows umans have thsh e same capability (17). Extrinsic focus. A major inhibitor of intensity is exercisers’ focus on intrinsic sensations such as breathlessness, burning and other uncomfortable feelings
(18,20). Rest‐based training uses strategies that focus participants away from these intrinsic sensations to more extrinsic factors. Workout parameters change quickly, monotony is minimized, circuits are utilized, exercise timing is limited and different movement strategies are incorporated in the same workout. All of this is designed almost as a distraction technique so the exerciser focuses more on what they are oing versus what they are feeling. This helps them work harder and therefore rest ore often.
dm Self determined. In psychology research Self Determination Theory posits that when people are given control and choice over their options internal motivation automatically increases (10‐12). With RBT, there is structure in the workout, but the exerciser is left in complete control over how hard to work, when to rest, for how long, and even has flexibility over exercise choice and modifications. These factors erve to not only increase the quality of work within a session (17), but can also mprove exercisesi adherence from session to session (10‐12,18‐19, 21). Time conscious. Given time and intensity are so closely linked, harder workouts by necessity must be shorter. RBT workouts can be as short as a 1‐minute bursts repeated multiple times throughout the day, to as long as 40 minutes of continuous xercise employing start and stop working and resting. Workouts lasting over 40 inutes suffer in intensity and may have negative hormonal consequences (13‐16).
em Final thoughts. Work and rest ratios employed by traditional interval and weight lifting workouts work for some but are an imperfect fit for most. By focusing on rest in a workout, and allowing exercisers control over when they rest and for how long, optimal intensity for results can be achieved in a safe scalable way. A 96 year old grandfather would be able to use the same workout approach to deliver optimal intensity for him, while a 24 year old elite athlete could use the concept to deliver an ntensity optimal for him or her. Rest‐based exercise can be seen as a new functional odel for fitness and fat loss.
im
efe en R
r ces:
1. Melanson, et. al. Exercise improves fat metabolism in muscle but does not increase 24‐hr fat oxidation. Exercise and Sport Sciences Reviews. 2009;37(2):93‐101.
2. Miller, et. al. A meta analysis of the past 25 years of weight loss research using diet, exercise or diet plus exercise intervention. International Journal of Obesity. 1997;21:941‐947.
sting 3. Trapp, et al. The effects of high‐intensity intermittent exercise training on fat loss and fainsulin levels of young women International Journal of Obesity. 2008;32:684‐691
4. Schuenke, et. al. Effect of an acute period of resistance exercise on excess post‐exercise d oxygen consumption: Implications for body mass management European Journal of Applie
Physiology. 2002;86:411‐417. 5. Osterberg, et. al. Effect of acute resistance exercise on post‐exercise oxygen consumption
and resting metabolic rate in young women. International Journal of Sport Nutrition and Exercise Metabolism. 2000;10(1):71‐81.
6. Treuth, et. al. Effects of exercise intensity on 24‐h energy expenditure and substrate oxidation. Medicine and Science in Sport and Exercise. 1996;28:1138‐1143
7. Scott, et. al. Misconceptions about aerobic and anaerobic energy expenditure. Journal of the International Society of Sports Nutrition. 2005;2:32‐37.
8. Scott et. al. Contributions of Anaerobic Energy Expenditure to Whole‐body Thermogenesis. Nutrition and Metabolism. 2005;2:14.
th 9. Scott, et. al. Energy expenditure before during and after the bench press. Journal of Strengand Conditioning Research. 2009 Mar;23(2)611‐618.
10. Deci, et. al. Self‐determination theory and basic need satisfaction: Understanding human development in positive psychology. Ricerche di Psichologia. 2004;27:17‐34.
ial 11. Markland, et. al. Motivational interviewing and self‐determination theory. Journal of Socand Clinical Psychology. 2005;24: 811–831.
12. Ryan, et. al. Self‐determination theory and the facilitation of intrinsic motivation, social development, and well‐being. American Psychologist. 2000;55:68‐78.
13. Jacks, et. al. Effect of exercise at three exercise intensities on salivary cortisol. Journal of Strength and Conditioning Research. 2002;16:286‐289.
exercise. 14. Kern, et. al. Hormonal secretion during nighttime sleep indicating stress of daytimeJournal of Applied Physiology.1995;79(5):1461‐8.
15. Karamouzis, et. al. The effects of marathon swimming on serum leptin and plasma neuropeptide Y levels. Clin Chem Lab Med. 2002;40(2):132‐6.
d duration. 16. Erdmann, et. al. Plasma ghrelin levels during exercise ‐ effects of intensity anRegul Pept. 2007;;143(1‐3):127‐35.
17. Edwards et. al. Self‐pacing in interval training a teleoanticipatory approach. Psychophysiology. Jun 1 2010. Published ahead of print.
18. Williams, et. al. Exercise, affect, and adherence: an integrated model and a case for self‐selected exercise. Journal of Sport and Exercise Psychology. 2008;30:471‐496.
19. Ekkekakis, et. al. Let Them Roam Free? Physiological and Psychological Evidence for the Potential of Self‐Selected Exercise Intensity in Public Health. Sports Medicine. 2009; 39(10):857‐888.
20. Duncan, et. al. Exercise motivation: a cross‐sectional analysis examining its relationships with frequency, intensity and duration of exercise. International Journal of Behavioral Nutrition and Physical Activity. 2010;7:7.
21. Rose, et. al. Exercise experience influences affective and motivational outcomes of prescribed and self‐slected intensity exercise. Scandanavian Journal of Medicine and Science in Sports. Jul 6 2010. Published ahead of print.
Rest‐Based Interval Training Jade Teta and Keoni Teta There is a built in limitation to interval training that is often overlooked. Standard interval training defines a set time you should be working along with a finite period of recovery. This can become an issue since not all exercisers are able to comply with these protocols. The work phase and rest component of intervals can be too long for some or not long enough for others. With true interval training the work phase is meant to push the body above the anaerobic threshold repeatedly. This is why a rest phase is necessary, because even elite athletes cannot maintain anaerobic intensities for long and therefore rest is necessary to generate repeated high intensity effort. This leads most practitioners of interval training to turn their workouts into aerobically based sessions with lower highs and higher lows. Rest‐based interval training is a technique we use to create adequate stimulation of the anaerobic physiology by allowing the individual to rest for as long as is required for heir own level of fitness to generate a higher intensity then would be otherwise tpossible. Whimpervals vs. Splintervals In order for interval training to be truly effective high‐intensity effort is essential. However, high‐intensity effort is the exercise equivalent to putting your hand on a burning stove, most people will not do it voluntarily. Often, trying to force someone to push themselves harder is like trying to get a cat to take a bath, they will resist it any way they can. With interval training this avoidance shows up in the form of pacing. People may go a little bit harder but fall short of full throttle exertion. We call intervals done this way “whimpervals”. Not to poke fun at our clients, they are only doing what is natural, but to point out the lack of results that will come from that approach. From a psychological perspective pacing on the sprint phase of an interval leads to a rest phase that will be higher in intensity than it should be. This pproach has very little difference from regular aerobic training since anaerobic aeffort is never truly reached. On the other end of the spectrum, you have what we call “splintervals”. This is an interval protocol that is so intense only the fittest of people could hope to do them. The work to rest ratios of these workouts is virtually impossible to maintain. Yet, these programs are the ones promoted in the mainstream fitness magazines and passed around the gym as if they were the ultimate weapon for fat loss. There is no question these types of routines generate big results for the 1% of the population that can actually do them, but for the other 99% these splintervals often turn into whimpervals or worse end up being unsafe. These routines are also very defeating ecause psychologically the exerciser will feel defeated and more apprehensive next orkout. A client that dreads working out will not be a client for long.
bw Rest‐based intervals
Rest and hard work are inextricably linked. The harder you work in any endeavor the more rest is required and the more rest taken in a workout the harder you will be able to work and the better results you will get. This truth is systematically ignored in the world of fitness and taken to mean rest between workouts rather than rest within workouts. Rest‐based intervals take the whole interval concept and turn it on its side so exercisers can look at it from a fresh perspective. The idea is too push as hard as possible on the work phase and then rest as long as necessary on the rest phase. While the work intervals are set, the rest intervals are not. In this way, the control of the workout is handed over to the exerciser. Rather than prescribing a 40 minute workout with defined work to rest ratios, rest‐based ntervals instruct exercisers to push as hard as possible for a particular time, but to irest as long as necessary until they are ready to go again. And we mean rest. We tell our clients they should be moving in literally slow motion during the resting phase and to maintain that pace until they feel 100% certain they can exert the same intensity once more. Finally, rather than setting a set number of intervals within a particular time, we instruct our clients to do as many interval rounds as possible in a given amount of time. In this way, they can see that they are mproving with each workout yet never have to dread a two‐hour workout just ibecause they require more rest. This approach has immediate consequences because it effectively individualizes the protocol for those who are super fit and those who are not. More importantly, exercisers feel in control, feel safe and leave the gym feeling accomplished. In our opinion, regularly employing one‐size‐fits‐all interval protocols is a big mistake that leads to a few people getting results but most lagging far behind their potential. est‐based intervals are our form of individualized interval training that adapts to
tocol. Rall fitness levels. Here is our beginning pro Here is our Rest‐based interval program: 20 second full exertion sprint followed by slow motion rest as long as is required 30 second full exertion sprint followed by slow motion rest as long as is required
ired ired
40 second full exertion sprint followed by slow motion rest as long as is requ60 second full exertion sprint followed by slow motion rest as long as is requRepeat this sequence for 30 minutes achieving as many rounds as possible.
Rest‐Based Training y Jade Teta & Keoni Teta B Rest and exercise are usually thought of as opposites, but they are actually complimentary and dependent upon one another. Just as night can only be defined in the context of day, exercise and rest are similarly connected. Rest is the single iggest determinant of exercise intensity. Without intense workouts, fitness results bwill be lacking and without rest, intensity will be compromised. Think about it this way: a champion sprinter who attempts to sprint two 100‐yard dashes immediately back to back with no rest will see a serious drop in intensity during the second race. The intensity generated in the first race would severely impede the performance of the second. With no rest between races, the sprinter could not physically or mentally muster the same effort. Resting between the two aces is required to reset the body. Only with rest would the sprinter be able to rpush his body to its max for a second time. The above scenario illustrates the concept of rest‐based exercise. By focusing attention on rest during training, it is possible to reset both mental and physical capacity to achieve more than would be possible without it. Rest‐based training is a new training philosophy that preaches that rest in a workout is not only a good hing, but should be the primary goal of any training program focused on delivering eal results. tr The pacing effect If we told you we want you to run as hard and as fast as you can for 10 minutes, what would you do? Assuming you were up for a challenge, you might take off running. However, you would certainly not be able to run as hard and as fast as you are capable for the entire 10 minutes. Even the most elite athlete cannot sustain top intensity for more than 60 seconds. On a 10 minute run, you would necessarily need to control yourself. You know that in order to make it 10 minutes without stopping, not only could you not run your hardest, but you would need to regulate yourself. In fitness and athletics, this is called pacing and it is synonymous with long distance running and aerobic exercise. But if instead we asked you to run as hard and as fast s you can for 10 seconds, not only would you physically be able to do it, you would abe more mentally up to the challenge. When it comes to results‐based fitness, pacing is a poor strategy for success because it is the antithesis of intensity. If you are pacing, than by definition you are not pushing as hard as possible. Pacing is also psychologically defeating. The example of the 10 minute run versus the 10 second run illustrates this point well. When pacing is employed as an exercise strategy, it automatically creates a built‐in intensity ceiling. With the popularity of aerobic exercise and traditional bodybuilding workouts, duration of exercise has wrongly been credited as the chief
driver of results. However, this is untrue for every parameter of fitness you may choose to measure. Higher intensity exercise excels at strength gains, delivers greater fat loss, and improves aerobic capacity far beyond workouts that are of onger duration and lower intensity. Yet in order to train at higher intensity, rest ust be employed.
lm Physiology of rest When the body is given a chance to rest and recover from a strenuous bout of movement, several beneficial physiological effects take place. Intense exercise generates metabolic byproducts that force the body to slow down. These byproducts are not necessarily a bad thing and their presence is meant to both protect the body and rebuild it after the workout has ended. However, they do interrupt the ability to sustain top performance. Most of us know that familiar burning sensation and extreme breathlessness that accompany hard physical effort. short rest during this type of movement gives the body time to clear these Ametabolic byproducts, making maximum physical exertion possible once again. Pacing has the opposite effect of rest‐based training because it never approaches the intensity level required to produce these beneficial metabolic byproducts. As a matter of fact, the very purpose of pacing is to avoid the metabolic acidosis created from intense muscle action. In rest‐based training, the biochemicals released from vigorous exercise are harnessed and used to create results. Lactic acid and other biochemicals released through intense exercise are some of the same molecules that induce the beneficial hormonal responses that grow muscles, increase endurance, and burn fat. Resting in a workout allows for the release of these chemicals one time after another. While it may take a marathon runner hours to reach this state, with est‐based exercise it becomes possible to harness this metabolic effect multiple imes throughout one workout. rt Rest and muscle recruitment Another important physiological mechanism is the use of muscle fibers. The body only uses the amount of muscle tissue required by the intensity of exercise. Lower intensity exercise uses less muscle fibers and high intensity exercise uses more. This effect is largely due to the fact that low intensity exercise only activates Type 1 muscle fibers. However, both Type 1 and Type 2 fibers are engaged during higher intensity exercise. Type 2 muscle fibers are perhaps the most important of the fibers, as they are involved in high‐speed, power‐type movements and have a greater capacity to grow, compared to Type 1 fibers. As exercise becomes more vigorous, the body is forced to engage more and more muscle tissue and Type 2 fiber timulation increases. As the intensity rises further, so does the amount of smetabolic waste and muscle fatigue. In a paced workout, the goal would be to hold back and go slower so the muscles involved never get to a place of full fatigue and failure. In this scenario, only Type 1
fibers are engaged. However, in a rest‐based workout, the very idea is too push the body to its limit engaging as much muscle tissue and releasing as many metabolic byproducts as possible. Training this way improves performance and results by ncreasing the amount of metabolic acidosis the body can tolerate and training the ibody to recruit more muscle tissue during exercise. When working muscle fatigues, more muscle fibers are recruited to sustain movement. There is a point at which pushing even one more second is impossible, as the body approaches its failure point. It is at this point when the use of a brief rest allows the body to recoup just enough so that the muscle can be attacked once again with increased demand. During this second bout, the muscles will fatigue even quicker and the body will be forced to respond with even greater muscle recruitment. The effect is exponential as the rest‐based workout proceeds. Inserting rest within intense exercise allows the body to engage more muscle than it would ave been able to otherwise because the metabolic byproducts are cleared during est but the muscles never fully get to recover. hr A few studies One interesting study in the February 2004 issue of the International Journal of Sports Medicine demonstrates the above points. In this study, four weeks of sprint training compared to standard aerobic exercise resulted in an increased ability to activate more muscle fibers in the legs in response to exercise. There was also a greater release of and tolerance for lactic acid in the sprint training group. These two affects would be highly beneficial in terms of performance for athletes and body composition changes for novice exercisers. Sprint training is impossible without rest between bouts. Another article from the Journal of Applied physiology (Nov 2007) shows Type 2 fibers are activated to much less a degree when exercise is continuous and sub maximal. And, in a resistance training study using brief one‐second rest periods combined with various intensities of leg contractions, it was shown that short rest combined with high intensity contractions had the greatest affect on uscle fiber recruitment. This study was published in the European Journal of hysiology (Aug 2004 Vol 92). mP Intervals versus Restbased Interval training is a popular concept in exercise that takes advantage of rest periods inserted in the workout. Rest‐based workouts differ from interval training because there is no set time limit on how long to work and when to rest. Interval training prescribes a very definitive “work phase” with a finite “rest phase.” Rest‐based training attempts to eliminate the pace effect that is still a prominent factor in interval training. As we said before, elite athletes cannot sustain an all‐out effort for more than 60 seconds, which means the average exerciser’s full speed limitations are probably closer to 15‐30 seconds. Some interval routines prescribe intervals up to 4 minutes in length, which means that pacing will still occur.
An interval training routine treats everyone the same by defining the exact amount of time one should push and the exact amount of time one should rest. While interval training is definitely superior to paced exercise in terms of generating results, rest‐based takes it one step further. In rest‐based workouts, the goal is to push as hard as possible for as long as possible with no pacing what so ever. And when rest is achieved through failure, rest only lasts as long as it takes to be able to deliver the same degree of intensity once again. This element of the training means that any exerciser at any fitness level can self‐tailor the workout to his or her exact specifications. An elite athlete may be able to go all out for a minute in a full throttle sprint, while a frailer older adult may only be able to last 10 seconds in a fast‐paced alk. But the idea is not limited to cardiovascular activities. Rest‐based training is xtremely useful in the resistance‐training world as well. we Psychology of Restbased training Like interval training, rest‐based workouts excel at producing fat loss and increasing aerobic capacity. However, rest‐based training has one key advantage over interval training: psychologically, interval training is hard. One of the major deterrents to interval training is the strenuous nature of the activity. Many people would rather do paced workouts and suffer with poor results than do interval training and suffer through a grueling workout. The rest‐based approach is just as demanding as interval training but has one important distinguishing quality: the exerciser is in full ontrol of when they take a break. This small little detail is a huge psychological cbenefit to the exerciser. As noted previously, if you are told to run all‐out for 5 minutes or 10 seconds, you will be much more likely to push harder for 10 seconds. However, if we take it one step further and say “Push as hard as you can until you cannot push anymore, and then rest as long as you need to until you can do it again” we have just removed a huge psychological barrier to exercise. Time and lack of control in exercise are anxiety‐producing. We would all like to know exactly how long we are going to be working and also be able to decide when we can rest because it guides us on how hard we will actually push. Whether we pace or truly push our physical capacity is dependant on time and control. Rest‐based training puts complete control of work and rest intervals into the hands of the exerciser. This one small change drastically mproves exercise adherence, intensity, and safety. It is like reverse psychology for xercisers. ie Final Thoughts The rest‐based approach to exercise can be used for both aerobic and resistance training. This style of training has benefits in muscle fiber recruitment and elicits the same biochemical responses of interval training. The important thing to remember is that the rest should be as brief as it takes to recover and push hard a second time. The wording we like to use is “push until you can’t, then rest until you
can”. In most interval style workouts, the rest periods are far too long for some or too short for others. The rest‐based approach allows each exerciser to individually tailor the work and rest intervals for their unique level of fitness to generate big results. Switching your standard interval workouts and resistance training programs to a rest‐based format will pay big dividends.
New Insights on Exercise for Weight Loss Jade Teta ND CSCS and Keoni Teta ND CSCS. Exercise prescriptions for weight loss have long been dominated by aerobic exercise like jogging, biking, or swimming. This is despite the fact that recent and past research shows aerobic exercise provides very little benefit over diet alone when it comes to body change. Anaerobic exercise, long ignored in discussions of weight loss, may provide unexpected benefit through previously ignored mechanisms. Both resistance exercise using weights, and interval cardiovascular xercise that alternates periods of intense exertion with rest, may provide superior enefits for weight loss with minimal investments in time. eb D erobic exercise work? A recent study by Dr. Edward Melanson published in Exercise and Sport Science reviews April 2009, was widely reported in the media as proof against the metabolism stimulating potential of exercise (1). However, this study looked almost exclusively at moderate intensity aerobic exercise like jogging, biking or swimming. What it showed was aerobic exercise of moderate intensity did not provide a metabolic advantage aside from the calories burned during activity. A previous meta‐analysis done over a 25‐year period came to a similar conclusion (2). This study analyzed the data from over 400 studies comparing diet alone, aerobic exercise alone, or diet plus aerobic exercise on weight loss. The results showed that aerobic exercise did not provide a significant advantage to weight loss over diet by itself. This information is shocking considering the pervasive belief among doctors nd the exercising public that long duration moderate intensity aerobic exercise is a roven modality for effective weight loss.
oes a
ap Aerobic vs. Anaerobic exercise While the ability of aerobic exercise to impact weight loss has been questioned, anaerobic exercise modalities like weight training and cardiovascular interval training have enjoyed increased interest. Before we go further it is useful to briefly review anaerobic and aerobic exercise. In very simple terms, aerobic metabolism takes place in the mitochondria and requires the use of oxygen. Anaerobic metabolism proceeds through a different pathway and requires neither the involvement of mitochondria or oxygen. It is well known that as exercise intensity increases anaerobic metabolism dominates; unfortunately, the exact anaerobic contribution to energy production is exceedingly difficult to measure. The standard way to approximate calorie expenditure and substrate utilization during exercise is through the measure of respiratory gases. The ratio of carbon dioxide expelled to oxygen consumed can give a predictable evaluation of not only energy use but also fuel utilization – glucose vs. fat. However, this method is only valid at lower exercise intensities. At higher intensities the relationship is less clear. To help address this error, researchers also measure EPOC (excess post‐exercise oxygen consumption). This is a measure of the recovery energy expenditure after exercise
and it has been thought to consist of anaerobic contributions to exercise as well. There is some argument as to how meaningful this EPOC effect can be. Many researchers claim the impact does not last long, only several hours, and amounts to at best 15% of total calories burned. However, these approximations come largely from studies with lower exercise intensities involving standard aerobic exercise protocols. Studies utilizing highly anaerobic protocols including cardiovascular interval protocols and weight training show a much different picture. In 2001, Schuenke et. al. showed a circuit resistance training program utilizing heavy weights, short rest periods and lasting only thirty‐one minutes was able to generate an EPOC that persisted for 48 hours (3). The results showed that metabolism 24 hours and 48 hours after the exercise session was increased by 21% and 19% respectively. The researchers point out that for a typical 180‐pound individual “This equates to 773 calories expended post exercise”. This is far from insignificant and greatly exceeds the 15% number many researchers quote for EPOC. Similar findings have been shown in women using a similar resistance training protocol. In women the elevation in metabolic rate lasted 16 hours (4). The same findings have been seen ith interval training as well with significant EPOC values lasting up to 24 hours (5‐). w6 Exercise Burn and “Afterburn” Dr. Christopher Scott of the University of Southern Maine is a pioneer in attempting to understand the full contribution of energy from both anaerobic metabolism and EPOC. He has published extensively in this area and is the author of one of the authoritative textbooks in this field entitled, A Primer for Exercise and Nutritional Sciences: Thermodynamics, Bioenergetics, and Metabolism (13). In his works, Dr. Scott points out that EPOC does not fully explain anaerobic energy use and that the anaerobic contributions to exercise may be even greater than originally thought, especially where lactic acid production is concerned. Dr. Scott emphasizes that to fully account for calories burned during exercise three components must be measured: calories burned aerobically during exercise, calories burned aerobically after exercise (EPOC), and anaerobic calories burned from exercise (7‐11). EPOC and the y anaerobic lactic acid measurements for exercise are considered separate bDr Scott.
In 2005 Dr. Scott published a paper entitled Misconceptions about Aerobic and Anaerobic Energy Expenditure where he explains his argument and highlights one of his studies comparing a 3.5‐minute aerobic exercise challenge with three work‐equivalent 15‐second sprints (7). When he compared the aerobic calorie use during the exercise bouts he found the aerobic challenge burned 120KJ or 29 Kcal, while sprinting used only 16KJ or ~4 Kcal. However, when he added on the measure for EPOC the calorie comparison for the two exercise bouts became close to equal rising to 149KJ or 36 Kcal for the aerobic bout and 165KJ or 39 Kcal for the sprint exercise. Finally, he added on the anaerobic contribution (blood lactate measure). At this point the numbers for the anaerobic sprint exercise rose significantly. The final tally was 165KJ or 39 Kcal for the aerobic exercise compared with 273KJ or 65 Kcal for the sprint exercise. By adding both EPOC and the anaerobic contribution to
the original calorie total, the sprint exercise was shown to far surpass the aerobic exercise in calories burned. This is striking when one considers the aerobic exercise session took over 4 times longer to complete (210 seconds vs. 45 seconds). What is most compelling is that without including both EPOC and anaerobic expenditure rom lactate to the energy totals, a full 94% of the calories used during sprinting fwould go uncounted. Dr. Scott has demonstrated a similar underestimation of energy use in weight training. In studies published in 2006 and 2009 in the Journal of Strength and Conditioning Research, Dr. Scott quantified anaerobic energy use during weight lifting (9,12). Using his method of measuring and quantifying all three components of calorie burn (aerobic metabolism during exercise, EPOC, and anaerobic ontributions by lactate) he was able to show that weight training exercise burns 0% more calories than originally thought. c7 Final thoughts: In light of this new understanding regarding exercise and weight loss, the caloric contribution for anaerobic exercise can be substantial. Given the much shorter durations of exercise required and the long exercise after‐burn elicited, anaerobic exercise can make significant contributions towards creating caloric deficits for weight loss. It seems wise for healthcare providers to adjust their weight loss recommendations regarding aerobic exercise to include anaerobic modalities as well. A strong anaerobic exercise program involving both weight training and cardiovascular interval training would be a wise addition to aerobically centered eight loss programs. This new understanding provides much needed tools in the attle against obesity related illnesses and their complications. wb
efe nc R re es:
1. Melanson, et. al. Exercise improves fat metabolism in muscle but does not increase 24‐hr fat oxidation. Exercise and Sport Sciences Reviews. 2009;37(2):93‐101.
cise 2. Miller, et. al. A meta analysis of the past 25 years of weight loss research using diet, exeror diet plus exercise intervention. International Journal of Obesity. 1997;21:941‐947.
3. Schuenke, et. al. Effect of an acute period of resistance exercise on excess post‐exercise oxygen consumption: Implicationsfor body mass management European Journal of Applied Physiology. 2002;86:411‐417.
4. Osterberg, et. al. Effect of acute resistance exercise on postexercise oxygen consumption and resting metabolic rate in young women. International Journal of Sport Nutrition and Exercise Metabolism. 2000;10(1):71‐81.
tabolism. 5. Tremblay, et. al. Impact of exercise intensity on body fatness and skeletal muscle meMetabolism. 1994;43:814‐818
6. Treuth, et. al. Effects of exercise intensity on 24‐h energy expenditure and substrate oxidation. Medicine and Science in Sport and Exercise. 1996;28:1138‐1143
7. Scott, et. al. Misconceptions about aerobic and anaerobic energy expenditure. Journal of the International Society of Sports Nutrition. 2005;2:32‐37.
8. Scott et. al. Estimating total energy expenditure for brief bouts of exercise with acute recovery. Applied Physiology Nutrition and Metabolism. 2006;31:144‐149.
r 9. Scott, et. al. Contribution of blood lactate to the interpretation of total energy expenditure foweight lifting. Journal of Strength and Conditioning Research. 2006;20:21‐28.
10. Scott et. al. Contributions of Anaerobic Energy Expenditure to Whole‐body Thermogenesis. Nutrition and Metabolism. 2005;2:14.
11. Scott, et. al. Direct and indirect calorimetry of lactate oxidation: implications for whole‐body energy expenditure. Journal of Sports Science. 2005;23:15‐19.
l. Energy expenditure before during and after the bench press. Journal of Strength itio Mar;23(2)611‐618.
12. Scott, et. aand Cond ning Research. 2009
13. Scott CB, A Primer for Exercise and Nutritional Sciences: Thermodynamics, Bioenergetics, and Metabolism. Human Press. 2008
New Perspectives on Lactate & Lactic Acid Jade Teta ND, CSCS and Keoni Teta ND, LAc., CSCS
Lactic acid, or more accurately lactate, is perhaps the most misunderstood compound in all of exercise metabolism. It has historically been blamed for the cause of acidosis during intense exercise and the subsequent muscle “burn” that accompanies vigorous exertion. More recent understanding has changed the historical perspective on lactate metabolism. Lactate is actually a physiological buffer against changes in pH protecting against, rather than causing, acidosis. In addition, lactate has several other surprising actions that have led several researchers to refer to it as a “lactormone” since it seems to have hormone like action as a signaling molecule. Lactate is proving itself as a much more complex layer in exercise metabolism. Understanding this new science provides several ew insights about exercise and its benefits. pn Brief review of lactic acid Lactic acid was first discovered in milk, hence the relationship to the word lactation, as in milk production. Although many use the two terms interchangeably, lactic acid and lactate are two different compounds. Roberg, et al (2004) showed that lactic acid is actually not produced in the body, but rather lactate is the actual compound found in human metabolism (6). During intense exercise, when the aerobic capacity is maxed‐out, hydrogen ions build up along with pyruvate. It is the hydrogen ions that cause the acidosis and generate the muscle burn, NOT lactate. As hydrogen ions accumulate, they combine with pyruvate to form lactate. In this regard, lactate can be seen as a physiological buffer acting to protect the body against the sharp rise in hydrogen ions and a lower pH. Once lactate is formed it can stay in the cell and be burned for energy through conversion back to pyruvate, or it can leave the cell and be burned for fuel in the same way in other cells. Lactate is also a key substrate for gluconeogensis both during and after exercise. Most interesting, is the realization hat lactate may have a key role in energy metabolism and cellular signaling rossing over into hormone‐like action. tc Lactate and energy expenditure New research on lactate shows it may have a significant impact on energy use during exercise. This is an effect that is undetectable when respiratory gases are captured to infer energy expenditure. The ratio of oxygen consumed to carbon dioxide expired is used in almost every study done on energy use and exercise. However, this procedure infers that all energy reactions take place in the mitochondria. Anaerobic energy use does not require either oxygen or the mitochondria, thus complicating energy calculations during intense exercise. Researchers have circumvented this situation by measuring aerobic energy metabolism after intense exertion, a measure called EPOC (Excess Post‐Exercise Oxygen Consumption). This is done because it is assumed that all the energy from
anaerobic metabolites (i.e., lactate) ultimately find their way back to mitochondrial respiration. However, this process is not as simple as it at first appears. Energy is lost in the conversion from pyruvate to lactate and from lactate back to pyruvate. This energy, lost as heat, cannot be measured from the capture of respiratory exchanges either directly or inferred indirectly as EPOC. Dr. Christopher Scott out of the University of Southern Maine has written several papers on this and has shown that lactate production needs to be considered separate from aerobic energy use and EPOC (5). In his papers he has shown neglecting this calculation can result in underestimating energy production during intense exercise by 40% (5). In his regard, anaerobic exercise such as sprinting and weight training may be urning significantly more calories than was once thought. tb Lactate improves metabolic efficiency. Lactate has been correlated with several positive benefits to exercise. It is now believed lactate is directly related to some of these beneficial changes through hormone‐like action. As exercise intensity escalates there is a large surge in catecholamine production. This occurs to supply the body with much needed blood sugar to fuel the intense exercise. As the exercise intensity increases aerobic physiology becomes “maxed out” forcing the body to become more anaerobic. This switch, was believed to be due to an oxygen deficit, but is now understood to be related to mitochondrial shuttle saturation. When this occurs, pyruvate and hydrogen ions begin to accumulate in the cytosol. It is the accumulation of hydrogen ions that lowers the pH of the cell causing fatigue and the familiar muscle burn of intense exercise. In this situation, lactate is quickly formed. Lactate can then be recycled back to glucose via gluconeogenesis, be burned directly by conversion back o pyruvate and entry into the Krebs cycle, and/or engage cellular machinery as a tsignaling molecule. The major signal sent by lactate during exercise seems to be an “adaptation signal”. When analyzing this action, lactate has two major functions: first, it increases cellular events leading to mitochondrial generation (7,12), and second, it stimulates the release of growth promoting hormones including HGH and testosterone (2,4,9). The major action on cellular signaling seems to be the up‐regulation of MCT‐1 (7). MCT‐1 is an embedded protein in the mitochondrial membrane that speeds the formation of pyruvate from lactate thus making existing mitochondria more efficient. In addition, research by Hashimoto et. al. in 2007, elucidated a complex mechanism whereby lactate interacts directly with key genes involved in mitochondrial biogenesis (12). Taken together, this opens a whole new understanding for improving metabolic efficiency. By harnessing the power of actate mitochondrial levels can be increased and enhanced resulting in many eneficial effects on total physiology. lb I s lactate a hormone?
The idea of lactate as a hormone is a novel concept. But it has been made clear through several studies over the last few years that lactate is a key signaling molecule in exercise metabolism. Interestingly, a lactate receptor called GPR81 was recently isolated in rats confirming it does indeed act like a hormone (1). Other studies have shown lactate can directly stimulate the release of testosterone, progesterone, and HGH (2‐4,9). In the case of testosterone and progesterone, this action is not mediated through LH, but instead seems to be a direct stimulation. This lends further credibility to lactate’s role in helping the body adapt and grow. Testosterone and HGH in particular are key players in human metabolism, especially as it pertains to physique development and combating obesity. estosterone and HGH, in addition to other effects, increase lean muscle tissue and ecrease fat mass. Td Final Thoughts Given its key involvement in exercise metabolism, physicians, personal trainers and fitness enthusiasts should be aware of the new understanding surrounding lactate. Lactate seems to be a key adaptive signal for human physiology. The smart utilization of anaerobic exercise modalities, in addition to the known benefits of aerobic exercise, may play a role in multiple functional disturbances underlying obesity and other metabolic disorders. If harnessed correctly, the adaptive signal roduced by lactate may provide new potentials for prescriptive exercise and isease. pd
1. Liu, et. al. Lacate inhibits lipolysis in fat cells through activation of an orphan g‐protein‐coupled receptor, GPR81. Journal of Biological Chemistry. 2009 Jan;284(5):2811
2. Ho Lin, et. al. Stimulatory effect of lactate on testosterone production by rat leydig cells. Journal of Cellular Biochemistry 2001;83:147‐154.
3. Lu, et. al. Lactate stimulates progesterone secretion via an increase in CAMP production in exercised female rats. American Journal of Physiology. 1996;271:E910‐5.
4. The role of lactate in the exercise‐induced human growth hormone response: evidence from McArdle disease. British Journal of Sports Medicine 2009;43: 521‐525
diture. 5. Scott, et. al. Misconceptions about aerobic and anaerobic energy expenJournal of the International Society of Sports Nutrition. 2005;2:32‐37.
6. Robergs, Et. Al. Biochemistry of exercise‐induced metabolic acidosis. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology. 2004;287:R502‐R516.
7. Hashimoto, et. al. Mitochondrial lactate oxidation complex and an adaptive role for lacate production. Medical Science in Sports and Exercise. 2008;40(3):486‐494.
8. L.B. Gladden. Lactate metabolism: a new paradigm for the third millennium. Journal Physiology. 2004;558(1):5‐30.
9. Luger, et. al. Plasma growth hormone and prolactin responses to graded levels of acute exercise and to a lactate infusion. Neuroendocrinology. 1992;56:112‐117. en. A “lactatic” perspective on metabolism. Medicine and Science in
Exercise. 2008;40(3)10. L.B. Gladd
Sport and :477‐485. 11. Scott CB, A Primer for Exercise and Nutritional Sciences: Thermodynamics, Bioenergetics, and Metabolism. Human Press. 2008
12. Hashimoto, et. al. Lactate sensitive transcription factor network in L6 cells: activation of MCT1 and mitochondrial biogenesis. FASEBJ. 2007;21(10):2602–2612.
TJhe Integrated Workout ade Teta and Keoni Teta
Obesity is the biggest health challenge of this century yet there is incredible confusion about effective management strategies. In this months column we cover a new science based workout protocol doctors can prescribe to their patients. It develops health, fitness and most importantly fat loss. It is called the integrated workout.
Most people concerned about health and fitness have asked at some point, “should I do my cardio before my weights or vice versa?” The answer appears to be neither and both. Several studies over the last few years have shown that the intermixed combination of cardiovascular exercise and weight training into one workout may be superior to separating the workouts or doing one after the other.
Before we get to the research and protocol, it is important to deal with some nomenclature. Workouts that combine cardiovascular exercise and weight training into one session are called concurrent workouts. Concurrent workouts do not separate the two exercise modalities, but rather do the two sequences back‐to‐back without rest. These workouts have always been done either one of two ways. Either cardio was done first and weight training was done second or cardiovascular exercise was preceded by weight training. Strict exercise physiologists would say that the order of the two sessions does not matter. They argue as long as the work done is ld exactly the same, the amount of calories burned and therefore fat lost shoube equal. New research shows this may not be the case.
Davis et al. and colleagues at the University of California at Santa Cruz and the University of California at Berkley published three separate studies that appeared in the January 2008 and September 2008 issues of the Journal of Strength and Conditioning research (1‐3). These studies looked at a different way of combining concurrent workouts and found that the order does indeed matter.
The most remarkable of these three studies took 28 women, divided them into 2 groups and tested them before and after a 3 days per week exercise protocol that lasted 11 weeks (2). One group of women did a traditional concurrent exercise program where they did weight training immediately followed by cardiovascular exercise on a treadmill. The other group did the same weight training routine and did the same amount of cardiovascular exercise. The difference was the second group did the cardiovascular exercise wedged between sets of weight lifting. A weight training exercise was completed and then the exerciser immediately completed a 30 to 60 second vigorous run. The participants then went back and completed another set of weights and then repeated the run. The researchers called the latt p er scenario integrated concurrent exercise (ICE). The more traditional grouwas called serial concurrent exercise (SCE).
The results of the study call into question the common assumptions about the order of exercise. After 11weeks the results of the study showed the ICE group had significantly better outcomes in almost all measures compared to the SCE including 35.4% greater improvement in lower body strength, 52.8% greater improvement in lower body endurance, 28% greater improvement in lower body flexibility, 143.5% greater improvement in upper body flexibility, 82.2% greater
improvement in muscle gains, 991.8% greater loss in fat mass. That is almost a ten fold greater loss in fat.
It is interesting to note that an earlier study, in January 2008, on this protocol published in the same journal and by the same research group showed this style of training was able to decreased delayed onset muscle soreness (DOMS) when compared to the more traditional concurrent exercise session (3). DOMS is the soreness felt in exercised muscle one to three days after intense resistance training. This hints there is something about the integrated concurrent exercise session that speeds recovery from exercise. There are very few studies on exercise protocols that are able to simultaneously help you gain muscle and lose fat to such a striking egree as this study. Similar results have been seen by other researchers using
xercise protocols (4‐5). dcomparable e How to do it Prescribing the integrated workout involves choosing 4 exercises that work big muscle groups. We suggest bench press, leg press, back row, and shoulder press. Instruct the completion of 5 sets of 10 reps using a 10 rep max (10RM). This is a weight a person can do 10 times but not 11. Then, between each set, have the patient complete a 30 to 60 second bout of what the researchers call of “cardioacceleration. This can be a steep incline walk, a sprint on a stationary bike, squat jumps or any exercise that spikes the hearty rate and strongly engages the ardiovascular system. The protocol can be done in straight sets, or in circuit
as each exercise is followed by a “cardio burst”. cfashion so long Final thoughts Obesity is becoming an ever‐increasing challenge. Smart exercise protocols that are simple, save on time, and deliver multiple fitness parameters are important. he integrated workout combines the best of cardiovascular exercise and resistance raining in one workout delivering, health, fitness and fat loss benefits. Tt
1. Davis, et al. Concurrent training enhances athletes cardiovascular and cardiorespiratory measures. Journal of Strength and Conditioning Research. 2008;22(5):1503‐1514.
2. Davis, et al. Concurrent training enhances athletes’ strength, muscle endurance and other measures. Journal of Strength and Conditioning Research. 2008;22(5):1487‐1502.
3. tiDavis, et al. Elimination of delayed-onset muscle soreness by pre-resistance cardioaccelerabefore each set. . Journal of Strength and Conditioning Research. 2008;22(1):212-225.
4. Paoli, et al. Effects of three distinct protocols of fitness training on body composition,
on
strength and blood lactate. Journal of Sports Medicine and Physical Fitness. 2010;50(1):43‐51.
5. Monteiro, et al. Acute physiological responses to different circuit training routines. Journal of Sports Medicine and Physical Fitness. 2008;48(4):438‐442.
WJeight Training, The
ade TeNew Cardio?
ta & Keoni Teta
Interval training has become the go‐to protocol for quick and efficient fat loss. Resistance training is also an extremely effective modality for not only muscle building, but fat loss as well. We regard resistance training as the original interval‐training workout. It now appears a combination of interval training and weight training intermixed together may be better than either one apart.
We say weight training was the original interval training because unlike aerobic exercise, rest was always built into resistance training protocols. The idea has always been to lift weights that are heavy enough to force the body to failure and then rest as long as is necessary to recover and repeat the same thing again. The quintessential example of this is the three sets to 10‐repetition protocol. This is where a weight is lifted in a particular exercise 10 times. The weight is usually a 10‐repetiti on max. In other words, it is a weight that can be lifted 10 times but not 11. This type of training is hard and cannot be done continuously without rest.
But what would happen if instead of resting completely between resistance xercise bouts, you were to do a cardiovascular interval instead before resuming the ext set of weight lifting? en Exercise is evolving Fitness has emerged from the aerobic dominated paradigm. Part of this evolution stems from a new understanding about anaerobic exercise. Anaerobic exercise is better described as “super‐aerobic exercise”. When you are anaerobic, you are automatically aerobic, although the reverse is not true. Some research
suggests anaerobic exercise may do a better job at improving aerobic capacity whencompared to aerobic exercise. An interesting study on scuba divers showed this effect. Scuba divers have a unique challenge given limitations that come with breathing from a regulator while swimming making them an interesting group to evaluate. The study was published in November 2007 in the Undersea and Hyperbaric Medicine Journal (1). The study compared anaerobic interval training with moderate intensity continuous training on aerobic capacity in these divers. VO2max increased by 18% in the anaerobic nterval group compared to 6% in the aerobic group. Swim speed of anaerobic raining was almost double that generated from aerobic exercise training. it How are you combining your workouts? Combining weight training and cardio workouts is a well‐known concept. Combination workouts usually take two forms. One where the aerobic exercise is done on one day and resistance exercise is done on another day. Another popular variation is to dothe resistance exercise and cardiovascular/aerobic training during the same session but independently of one another. In other words, the resistance training workout is either immediately preceded by the aerobic exercise or vice versa.
Using what we call a weight‐based interval approach may provide the best of both worlds. We have been using this technique for many years. It involves doing full‐body exercises with heavy weights and sprint‐based drills inserted continuously throughout the workout. Some of the sprints are done with weight (i.e., squat jumps holding dumbbells) and some are not (i.e., incline treadmill “sprints”, squat thrusts, or stair runs). The key feature of these workouts is it is virtually impossible to
ether the workout is an anaerobic or aerobic workout. It is actually ystems.
distinguish whtraining both s
A new study on weight based interval training
Two September 2008 studies both published in the Journal of Strength and Conditioning Research has dramatically validated the weight based interval approach (2‐3). The study was conducted by Dr. W. Jackson Davis, and completed out of the University of California at Berkley and Santa Cruz. Dr. Davis and his colleagues studied two different combination workouts. One workout was of the type typically practiced by personal trainers and fitness enthusiasts, and consisted of a 60‐minute resistance‐training workout followed by 30 minutes of aerobic exercise. This more typical routine was compared with a workout that alternated resistance training with what the researches called “cardioacceleration”, which was essentially a high intensity sprint on a treadmill. There was little rest between the “cardio sprint” and the next weight lifting exercise. All other aspects of the training volume were kept equal.
The workout that involved and interval weight training approach, where the two modalities were merged together instead of distinctly separated, outperformed the more traditional workout in almost every measure. The interval weight training approach created significant positive differences in lower body muscle strength and lower body muscle endurance. But the greatest effects were seen in body composition. The interval weight training group saw an almost 10‐fold (998%) reduction in body fat compared with the separated group. In addition to that, the
r weight based interval group had an 82.2% increased muscle gain over the othegroup Another interesting side effect of this style of raining was its impact on delayed onset muscle soreness (DOMS) (4). Dr. Davis published an earlier study in the January 2008 Journal of Strength and Conditioning Research showing this training method significantly reduced DOMS. This was an unexpected finding of the tudy and points to a synergistic effect on recovery when using and interval weight raining approach st Final thoughts
Exercise science is currently undergoing a revolution with many of the old ideas in exercise being turned upside down. The weight based interval approach seems to be able to offer the benefits of both aerobic and anaerobic training all within one compact integrated workout. With improved fitness and body
composition results, it can provide a useful clinical tool to positively impact health and fitness.
efe en R
r ces:
a 1. Wygela, et al. Optimization of fin‐swim training for SCUBA divers. Underse& Hyperbaric Medicine. 2007 Nov;34(6):431‐438.
2. Davis, et al. Concurrent training enhances athletes cardiovascular and cardiorespiratory measures. Journal of Strength and Conditioning Research. 2008;22(5):1503‐1514.
ce and other 3. Davis, et al. Concurrent training enhances athletes’ strength, muscle enduranmeasures. Journal of Strength and Conditioning Research. 2008;22(5):1487‐1502.
4. Davis, et al. Elimination of delayed‐onset muscle soreness by pre‐resistance cardioacceleration before each set. . Journal of Strength and Conditioning Research. 2008;22(1):212‐225.
