Resting Metabolic Rate: Clinical Relevance, Technology of Assessment, Factors Affecting Variability,...

Resting Metabolic Rate: Clinical Relevance, Technology of Assessment, Factors Affecting

Variability, and the Contributions of Aerobic and Resistance Training

University of Alabama – BirminghamOctober 7, 2003

Jay T. Kearney, PhD, FACSMV.P. Clinical Affairs, HealtheTech, Inc

Presentation Outline

• Establish the Clinical Relevance for Measurement of RMR– Statistics on Overweightness and Obesity– Obesity Prevention Toolbox– RMR as a large and increasing component of TEE– Contribution non-behavioral factors

• Technological Advances and Approaches for Measurement of RMR

• Clinical Conditions Required to Accurately Measure RMR– Pre- and measurement conditions– Linear additive model of error– Biological Variability

• Relationship between RMR and Lean Muscle Mass

• Summary and Discussion

““Americans of all ages, Americans of all ages, genders, ethnic backgrounds, genders, ethnic backgrounds, socioeconomic conditions socioeconomic conditions are getting more are getting more “nutritionally abundant” or “nutritionally abundant” or fatter!”fatter!”

Jay T. Kearney, yesterday, today and tomorrowJay T. Kearney, yesterday, today and tomorrow

Assertion

Professionally, we have been ineffective in communication of the need or rationale for, presenting the essential knowledges and

translating these into actionable steps necessary for the public to maintain or

achieve normal body weight

Why?

• Overweight = more than 10% over ideal body weight– Body Mass Index between 25 and 30– For 5’10” that is between 175 and 209– For 6’2” that is between 195 and 234

• Obese = more than 20% over ideal body weight– Body Mass Index greater than 30– Greater than 209 for 5’10”– Greater than 234 for 6’2”

• In the United States:– 2 out of every 3 adults is overweight– Rates of overweightness and obesity have doubled in 15 years– Becoming an increasing problem in youth

The U.S. Weight Problem

Obesity: National Health CrisisObesity Trends* Among U.S. Adults BRFSS, 1991

Source: Mokdad A H, et al. J Am Med Assoc 1999;282:16, 2001;286:10.

Obesity: National Health CrisisObesity Trends* Among U.S. Adults BRFSS, 1995Obesity: National Health CrisisObesity Trends* Among U.S. Adults BRFSS, 2000Obesity: National Health CrisisObesity Trends* Among U.S. Adults BRFSS, 2001

The U.S. Weight Problem• The Surgeon General recently stated that

overweight/obesity is the second leading cause of preventable death in the United States

• 65% of Americans are either significantly overweight or obese

• 300,000 deaths per year are directly attributable to being overweight or obese

• $100 billion annual U.S. spending on medical costs

Health Facts

• If the U.S. diet improved, the cost of treating heart disease, cancer, and diabetes could be reduced by at least $71 billion per year1

• Risk of type 2 diabetes increases 4% for every pound of excess body weight2

1. Frazao, E. (1999). High costs of poor eating patterns in the United States. In: America’s Eating Habits Changes and Consequences.

2. Vinicor, F., Burton, B., Foster, B. & Eastman, R. 2000. Healthy people 2010: diabetes. Diabetes Care, 23, 853-855.

Health Risks Associated with Obesity

The Surgeon General’s Call To Action, 2001

• Premature death• Type 2 diabetes• Heart disease• Stroke • Hypertension• Gallbladder disease• Osteoarthritis • Asthma• Cancer (endometrial, colon,

kidney, gallbladder, and postmenopausal breast cancer)

• High blood cholesterol• Complications of pregnancy• Menstrual irregularities• Stress incontinence• Increased surgical risk• Psychological disorders

such as depression• Psychological difficulties due

to social stigmatization

The Surgeon General’s Call To Action To Prevent and Decrease Overweight and Obesity 2001

• Promote the recognition of overweight and obesity as a major public health problem

• Assist Americans in balancing healthful eating and regular physical activity to achieve and maintain a healthy or healthier body weight

• Identify effective and culturally appropriate interventions to prevent and treat overweight and obesity

• Encourage environmental changes to help prevent overweight and obesity

• Develop and enhance public-private partnerships to help implement this vision

The Energy Balance Equation

RMR

Lifestyle

Exercise

Fat

Protein

Carbohydrate

Calories In-Consumption

Calories Out-Burn

Metabolism-The Burn Half of the Energy Balance Equation

• Metabolism, measured in calories, is the biochemical process of combining nutrients with oxygen to release the energy needed for the body to function.

• Measurement of metabolism is critical in weight management programs.

• The key to success is knowing and managing your personal metabolic rate.

The importance of RMR in energy balance increases linearly as the number of calories expended in purposeful work or play diminishesExample: JTK

RMR Energy Expenditure: Lifestyle, Occupation,

Exercise

Calorie Budget RMR/TEE

1900 1,200 3,100 61%

1,900 900 2,800 68%

1,900 600 2,500 76%

1,900 300 2,10085%

There is an increasing tendency for the lay public to believe that non-behavioral factors are dominant in regulation of the energy balance

• Genetic factors• Fast foods – taste, cost, availability• Increased prevalence of eating outside the home• Caloric balance between: Fats, CHO, and Protein• Portion distortion• Fat content of commercial foods• Etc.

Technological Advances and Approaches to Measurement• Original debate between direct and indirect calorimetry

• Because measurement has traditionally been difficult, many clinicians and dietitians have relied on estimates – classic is the Harris-Benedict Equation

• Gas analysis was all chemically based until the 1970s

• Douglas bag based gas collection and sample analysis

• Development of integrated metabolic carts followed in the late ’70s

• Two approaches – ventilated hoods (Delta Trac) and mouthpiece systems – Sensormedics

• New technology – MedGem – 2001

• Estimation of RMR based on measurement of other parameters– Tannita, based on body composition– Body Media, based on body surface temperature, GSR and others

Devices Used to Measure RMR

• Highly impractical• Expensive• Requires technical expertise

• Large, expensive machines• Difficult and costly to maintain• Requires frequent calibration

Douglas Bag Metabolic Cart

Introducing MedGem/BodyGem

• Measures VO2 to determine RMR

• Self-calibrating

• Accurate, validated and

scientifically-based

• Portable, lightweight and easy-to-

use

• Cost-effective and reimbursable

• MedGem is 510(k) cleared

• Proprietary technology platform

Recommended Pre-measurement Conditions

• In an attempt to assure the validity of RMR measurement done with the BodyGem®/MedGem® devices, HealtheTech recommends conservative set of pre-measurement guidelines. The required resting period remains at 10-15 minutes, but we also recommend that the client:

– abstain from eating for at least 4 hours.

– abstain from exercise (cardiovascular or resistance-training) for at least 4 hours.

– abstain from caffeine for at least 3 hours.

– abstain from nutritional supplements or medications containing ephedra, Ma Huang, or pseudoephedrine for at least 2 hours.

– abstain from nicotine for at least 1 hour prior to an RMR measurement.

– A simplified version of the test conditions that some of our customers are using is “the rule of 4s” – 4 hr. fast, 4 hrs since exercise, 4 hrs since other factors that may increase RMR.

Factors that Influence RMR

• Body mass– People with more mass will have a higher metabolism.

• Body composition– Muscle burns more calories than fat, even at rest.

• Age– RMR declines naturally in adults– Most of this is associated with the natural loss of muscle

mass.• Gender

– Men normally have a higher metabolism than women primarily because of size and body composition.

• Hormones– Certain hormones can increase or decrease metabolism.

Factors that Influence RMR

• Fever and/or infection– Increase in body temperature will increase RMR

• Pharmaceuticals/nutritional supplements– Certain prescription and OTC drugs and nutritional

supplements can increase or decrease RMR

• Nicotine– Increases RMR

• Caffeine– Increases RMR

• Ephedra/ephedra containing products– Increases RMR

Age-Related Decrease in RMR

• Is there a natural slowing of our metabolic rate as we age?

• There is a curvilinear relationship between age and RMR– Females: 0.6%/decade until the age of 50; 4%/decade

beyond– Males: No effect until 40; 6%/decade from 40 to 80

• There appears to be a relationship between the decline in VO2 max and the reduced RMR in males but not females

• Other factors suggested:– Decreased thermogenic responses – Golay, 1983– Altered sympathetic responses – Swartz, 1990– Altered distribution of fat stores – Enzi, 1986– Decrease in voluntary physical activity – McGandy, 1960– Largest component is associated with loss of FFM

170

180

190

200

145014751500152515501575160016251650

Weight (lbs) 196 192 190 188 184 179

Measured RMR162815861568153915301503

Start 1 Week

2 Week

4 Week

8 Week

12 Week

Poun

ds

Cal

orie

s pe

r da

y

Weight Loss and the Effect on RMR

Alexander, H.A. et al. Efficacy of a Resting Metabolic Rate Based Energy Balance Prescription in a Weight Management Program Obesity Research, Presented at Nutrition Week Conference, 2002.

Menstrual Status and RMR

• Normal cyclic variation is in the order of 6 to 8% - lowest about one week before ovulation, climbing until menstruation, then falling.

• A sustained increase of 7% over ½ a cycle provides a “free day” of burn each month

• This can be a delta of ~ 5 lbs/year

• Lowered RMR appears to be linked to reproductive disturbances– May reflect overall conservation of energy– Amenorrheic and eumenorrheic athletes generally have

lower RMRs– Similar in caloric intake, diet, body composition, activity level,

and thyroid hormones

Linear Additive Model of RMR Measurement Error

RMR Measured = RMR True+ Biological Variability + Technological Variability + Error

• Recognition of day-to-day variability in people• Limitation of technological problems• Use of specifically defined procedures

• How much difference is clinically relevant? When do you make different decisions?

Variability of Measured Metabolic RateHaugen and others, accepted for

publication – Journal of Clinical Nutrition

• Subjects: N = 37, 12 males and 25 females• Age 21 – 67 years• BMI 17 – 34• 4 RMRs taken on each subject; AM/PM; Day 1/Day 2• Sensormedics 2900 ventilated hood system• AM measurements after 12-hour fast, PM measures after 4-hour

fast• AM means 1,508 + 31.5 and 1,511 + 35.9• PM means 1,593 + 35.6 and 1,602 + 29.3• Highly correlated

Day 1 vs. Day 2, AM vs. PM

Confidence Intervals for the Absolute Differences

kcals

RMR Variability

Contributions to Resting Metabolic Rate

Tissue % of total body mass

Kgs in 70 kg Metabolic rate (kJ/kg. per day)

Contribution to RMR

(kJ per day)

Organ tissue: brain, heart, liver, kidney

5 – 6% 3.85 kg 1,424 5, 482

Skeletal muscle

40% 28 kg 60 - 125 1,680 – 3,500

Adipose tissue 15 – 20% 12.25 kg 10 – 30 125 - 350

Lean Muscle Mass or Fat Free Mass and Its Relationship to RMR

• Numerous studies have reported relationships between muscle mass and RMR in the range of r = 0.70 to 0.96

• Many early studies used cross-sectional methodologies to evaluate the relationship between training and RMR

• Exercise has been shown to slow the age-related decline in RMR

• Aerobic training has shown some, but generally minimal relationships to RMR

• Athletes using high-intensity training are and exception

• Resistance training’s impact is generally a function of the impact of the program on LBM

Effect of Aerobic Training on RMR

• Westerterp, 1998 Amer. J. Clinical Nutrition– Concluded there is no clear-cut long term effect

• Van Zant, 1992, Int. J. Sports Nutrition and Exer. Metabolism– There may be acute and chronic effects above 70% VO2

• Generally, is is doubtful is there is an effect in “normal” population

• Take home messages;– Intensity and volume appear to be important– The “in-need” groups have not and will not be able to

tolerate the intensity– Aerobic exercise/training is great for burning calories in the

moment – “Joy Riding”!– Example: 1 mile or 20 min / day = ~ 700 kcals/week = 10

lbs/year

Acute Effects of Resistance Training on “RMR”

• Comparable to the concept of EPOC – elevated post-exercise oxygen consumption

• Methodological questions relative to the definition of Resting MR

• About 10 studies in the literature

• The heavy majority show and increase in metabolic rate continuing for 60 to 120 min.

• When tested, most show continued elevation on the following day

• Intensity and resistance training experience appear to be factors

Chronic or Long Term Effect of Resistance Training on RMR

• If aerobic training is “joy riding”; then RT can “increase the idle”

• Absolute changes in RMR: Generally, if the FFM increases by 1 kg. or more there is an increase in RMR – kcals/ or kJ/day

• Adjusted RMR or metabolic rate adjusted for muscle mass may or may not change

• Mechanism to explain an increase in Adj. RMR is not clear – Winett and Carpinelli, 2001.

Author & year Change in FFM Change in RMR

Arciero, P.J., 2001

Metabolism

Increased 1.4 kg Abs. RMR increased sign.

Dolezal, B.A., 1998

J. Appl. Physiol.

Increased 2.3 kg. in RT

Increased 3.2 kg. in AT + RT

Abs. RMR increased in both

Adj. RMR increased, NSD

Broeder, C.E. , 1992

American J. Clinical Nutr.

Increased 2.1 kg Abs. RMR increased 3%,NSD

Poehlman, E.T., 1992

J. Clin. Endro. & Metabolism

Increased 1.3 kg Abs. RMR increased

Adj. RMR, NSD

Cullinen, K., 1998

J. Amer. Diet. Assoc.

Increased by 4.5% in 12 wks Abs. RMR increased 9%, NSD

Adj. RMR did not change

Summary of Studies that have Demonstrated Increases in RMR in Association with Resistance Training

Lemmer, J.T., 2001

MSSE

Increase in FFM by 1.0 to 2.0 kg

Men increased RMR by 9%

Both abs. and adj significant

Women did not increase RMR

Ryan, A.S., 1995

J. Appl. Physiol.

Increased by 1.1 kg. RMR increased by 4%

Sign. with RT and RT + diet

Byrne, H.K., 2001

J. Sport Nutr and Ex. Metab.

Increased by 1.9 kg. Abs. RMR up 44 kcals/day

Adj. RMR NSD

Pratley, R.E., 1994

J. Appl. Physiol.

Increased FFM 2.6% Abs. RMR up 7.7% SD

Adj. RMR up 5.1%, SD

Hunter, G.R., 2000

J. Appl. Physiol.

Increased by 2.0 kg. Abs. RMR increased, SD

Adj. RMR increased, SD

Campbell, W.W., 1994

Amer. J. Clinical Nutr.

Increased 1.4 kg. Abs. RMR increased 6.8% SD

Adj. RMR increased, NSD

Summary of Studies Demonstrating an Increase in RMR in Association with Resistance Training

Inclusion of Resistance Training in Weight Loss Programs for Obese Subjects

• Theoretical concept is excellent: Add Resistance Training, Maintain or increase FFM, Maintain or increase RMR, Weight loss is easier to achieve and maintain!

• The literature does not support the theory as well as we would like!

• 8 published papers reviewed: 2 RATS; 2 Positive; 4 Decrease or no difference between groups

• No evidence for increase in adj. RMR

• Critical factor is the impact of the resistance training program

• Personal bias – still include!

Energetics and Some Simple Math: We are designed to be kinetic beings!

• Typical RMR range from about 50 to 80 kcals/hour – 1,200 to 1,920 kcals/day

• ACSM equation for walking or running is ~ VO2 = 0.200 ml O2/kg/meter/min

• Covering a mile in 20 min. = 80 meters/min

• VO2 = 0.200 ml/kg X 80 meters/min = 16 ml O2/kg/min ~ 3 METS

• 16 ml O2/min X 70 kgs = 1.12 L O2/min

• At 5 kcals/L O2 = approximately 5 kcals/min or 100 kcals/20 min.

• The constant for conversion of ml O2/min to kcals/day is 6.93 – therefore at 1,120 ml/min this is equivalent to a daily metabolic rate of 7,762 kcals.

Questions and Discussion?

Thanks for your attention!

Author/YearPopulation Studied/ Sample Size

Resistance Training Program Details

Resting Metabolism Measurement Details

Primary Outcome Measure(s)/ Results for RT Groups

Author's Conclusions/ Reviewer Comments

Arciero, P. J., et al., Metabolism, 50, 1429, 2001.

30 healthy males (21 ± 3 yrs): Cr group, n = 10; Cr + RT, n = 10; placebo + RT, n

= 10

3 days/week for 1 month, 2x10 reps @ 70% 1 RM,

plus 3rd set to failure; resistance increased 5%

after 10 reps for set 3

Measured for 30-45 min following overnight, fasting stay in lab; computerized

open-circuit indirect calorimeter

TBW sig. > in Cr and Cr-RT (p < 0.01). FFM

sig. > Cr-RT (63.0 ± 2.8 to 64.7 ± 3.6 kg, p

< 0.01). Abs. RMR sig. > in Cr and Cr-RT

(p < 0.05).

The addition of creatine supplementation to RT

significantly increases total and FFM. Results

influenced by increase in TBW, therefore increase in

RMR may be independent of changes in FFM.

Dolezal, B. A., et al., Journal of

Applied Physiology, 85,

695, 1998.

30 physically active, healthy males (20.1 ± 1.6 yrs): RT

group, n = 10; AT group, n = 10; AT + RT group, n = 10

3 days/week for 10 weeks. For the first 2 weeks,

resistance set for fatigue to occur at 10-15 reps each

set; for final 8 weeks, resistance set for fatigue to occur at 10-12 reps for set

1, 8-10 for set 2, and 4-8 for set 3

Measured for 20 min following a 12 hr fast and a 30 min rest, with average of final 15 min used as RMR measure; computerized


FFM sig. > in both RT (65.0 ± 6.7 to 67.3 ± 7.1 kg) and AT-RT

(63.7 ± 6.9 to 66.9 ± 7.8 kg), both p < 0.05.

Abs. RMR sig. > in both RT and AT-RT. In RT, Adj. RMR > but

not sig. RMR (kJ/day) and FFM significantly correlated (r = 0.74, p

< 0.01).

Intense, periodized RT most likely promoted skeletal

muscle hypertrophy, which increased RMR by creating more metabolically active

tissue (FFM).

Broeder, C. E., et al., American

Journal of Clinical Nutrition, 55, 802,

1992.

64 males (18-35 yrs): RT group, n = 22; AT group, n =

22; control group, n = 20

4 days/week for 12 weeks. For first 2 weeks, 3x10-12 reps with resistance set to bring about fatigue after 10-

12 reps. Final 10 weeks done so fatigue reached at

10-12 reps on set 1, 8-10 on set 2 and 6-8 on set 3

Measured for 30 min following a 12 hr fast and a 30 min rest; computerized


FFM sig. > in RT group: from 63.8 ± 2.4 to 65.9 ± 2.6 kg (3.3%, p < 0.05). Abs. RMR increased 3%, but not sig. RMR and FFM

significantly correlated (r = 0.64, p < 0.02).

RT was effective in increasing FFM, may help prevent a decrease in RMR seen during negative energy

balance.

Poehlman, E. T., et al., Journal of

Clinical Endocrinology

and Metabolism, 87, 1004, 2002.

48 premenopausal women with BMI < 26 kg/m 2̂ (18-35 yrs): RT group, n = 16; AT group, n = 13; control

group, n = 19

3 days/week for 24 weeks. 10 reps per set (# of sets not specified) at 80% of 1-

RM for 9 exercises

RMR measured for 60 min after an overnight, fasted stay in lab; computerized


FFM sig. > in RT group (1.3 kg, p <

0.05). Abs. RMR sig. > in RT group (p < 0.05); no change in

Adj. RMR

Benefit of RT is in the direct energy cost of the exercise,

not due to a chronic elevation in in total daily

energy expenditure. Very good research design .

Cullinen, K., et al., Journal of the

American Dietetic

Association, 98, 414, 1998.

30 previously untrained young women (19-44 yrs): RT group, n = 20; control

group, n = 10

2 days/week for 12 weeks, moderate intensity. Started

with 2x10 reps at a baseline weight; when 3x10 reps was achieved, weight was increased. 6 different

exercises used.

RMR measured for 30 min following a 12 hr fast and a

30 min supine rest; computerized open-circuit

indirect calorimeter

In RT group, FFM > after week 8 (~3%), and sig. > by ~4.5%

(p < 0.0001) after week 12. Abs. RMR

increased a non-significant 9% in the RT group after week

12. Adj. RMR did not change.

Because mean increase in FFM was only 2 kg,

expected increase in RMR would be only 60 kcal, too

small to be significant. Increasing the amount of

skeletal muscle through RT may have less effect on total RMR than would be

expected with an increase in FFM

Lemmer, J. T., et al., Medicine and

Science in Sports and

Exercise, 33, 532, 2001.

40 male and female subjects divided into 4

groups: young men, n = 10 (20-30 yrs); young women,

n = 9 (20-30 yrs); older men, n = 11 (65-75 yrs);

older women, n = 10 (65-75 yrs)

3 days/week for 24 weeks. First 12 weeks done at ~5-RM load; second 12 weeks

done at ~15-RM load. Resistance was

progressively increased. Some variation in exercises performed in each 12 week

period.




All 4 groups had sig. > FFM after RT: ~2 kg in the younger groups and ~1 kg in the older

groups (p < 0.05). Combined, Abs. RMR in men sig. > by 9% (p < 0.001), and Adj. RMR was sig. > (p < 0.05). No change in women for Abs. or

Adj. RMR. Relationship be

Changes in absolue and relative RMR in response to

RT are influenced by gender, but not age.

Similar RMR response between young and older subjects was related to

similar increases in FFM in response to RT.






Ryan, A. S., et al., Journal of


818, 1995.

15 postmenopausal women (50-69 yrs): RT group, n = 8

(normal weight, BMI < 27 kg/m 2̂); RT + diet group, n

= 7 (obese, BMI > 27 kg/m 2̂)

3 days/week for 16 weeks. Resistance set at ~ 5-RM

for first 3-4 reps, then reduced so 11-12 more reps could be done. 14 different exercises done, with 2 sets for lower body exercises, 1 set for upper

body exercises




FFM sig. > in both groups combined. Not sig. > for either group individually,

though RT group went from 38.2 ± 1.0 to

39.3 ± 1.4 kg FFM, and RT + diet group went from 43.7 ± 0.4

to 44.2 ± 0.5 kg FFM. Both groups had non-significant increases

in RMR of ~

RT increases FFM in both normal-weight and obese

women, resulting in a higher RMR. Significance

achieved only when the two subject groups were

combined.

Byrne, H. K., et al., International Journal of Sport

Nutrition and Exercise

Metabolism, 11, 15, 2001.

19 previously sedentary, moderately obese women (mean age = 38.0 ± 0.9

yrs): control group, n = 9; RT group, n = 10; RT +

walking, n = 9

4 days/week for 20 weeks. For first 6 weeks, 3 sets of

10 to 12-RM; for final 14 weeks, sets of 10 to 12-

RM, 8 to 10-RM, 6 to 8-RM, respectively

RMR measured for 30 min following a 30 min seated

rest; average of measurement taken on 2

consecutive days; computerized open-circuit


Both groups had sig. > FFM (1.90 kg, p < 0.05). RT group had sig. > Abs. RMR (44 kcal/day, p < 0.05).

Not significant difference for Adj.

RMR.

RT can bring about a change in RMR through an

increase in FFM.

Pratley, R. E., et al., Journal of


133, 1994.

13 sedentary, but healthy men (50-65 yrs)

3 days/week for 16 weeks. Resistance set at 90% of 3-RM for first 3-4 reps, then reduced so 15 more reps

could be done. 14 different exercises done, with 2 sets for lower body exercises, 1 set for upper body exercises

RMR was measured for 30 min following a 12 hr fast and a 30 min supine rest; computerized open-circuit


FFM sig. > 2.6% (p < 0.05). Abs. RMR sig. > 7.7% (p < 0.001).

Adj. RMR sig. > 5.2% (p < 0.05).

Heavy RT increases RMR in healthy older men in part by

increasing FFM. Since RMR remained sig. > after

adjustment for FFM, suggests that increased

RMR also due to increased metabolic activity of FFM.






Hunter, G. R., et al., Journal of


977, 2000.

15 healthy, older adults, both men (n = 8) and

women (n = 7), age 61-77 yrs.

3 days/week for 16 weeks. 3x10 at 65-80% 1-RM

RMR was measured for 20 min following a 12 hr fast; computerized open-circuit


FFM sig. > by 2 kg (p < 0.01). Abs. RMR sig. > (p < 0.01) and Adj. RMR sig. > (p =

0.04).

RT is valuable for increasing RMR in older adults,

thereby improving their metabolic profile.

Campbell, W. W., et al., American Journal of

Clinical Nutrition, 60, 167, 1994.

12 older men and women with no prior RT experience

(56-80 yrs)

3 days/week for 12 weeks. 3x8-12 at 80% 1-RM for 4 exercises (2 upper body, 2

lower body)

Subjects reported to the lab in a fasted state and rested in a supine position for 45 min before measurment.

20 min before measurment, a milk-based beverage

comtaining 1/12 of daily energy and protein requirements was

consumed. RMR was measured for 20 m

FFM sig. > (1.4 ± 0.4 kg, p < 0.01). Protein plus mineral mass not significantly different.

Total body water (TBW) sig. > (1.6 ± 0.4 L, p < 0.01). Increase in FFM

highly correlated to increase in TBW (r = 0.841, p < 0.0006). Abs. RMR sig. > by

6.8% (p

RT is an effective way for older adults to increase

their energy expenditure, in part due to an increased

RMR. The increase in RMR is due to an increase in

metabolic activity of lean tissue and not an increase

in lean tissue mass.






Obesity is a multi-factorial disease that requires a multi-dimensional team

approach to its prevention and recovery.

Relationship between Lean Body Mass and RMR

• Cross sectional data

• Weight loss, loss of Lean Muscle Mass and Decreases in RMR

• Investigations of the effect of resistance training on RMR– Equivocal results in some studies – no change in

LBM, no change in RMR– Changes in LBM and increases in RMR

Resting Metabolic Rate: Clinical Relevance, Technology of Assessment, Factors Affecting Variability,...

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