Managing the Obese Patient,With Emphasis on Exercise

Kevin deWeber, MD

Family Physician

Primary Care Sports Medicine

USUHS

Objectives

• Review the benefits of exercise in obesity

• Discuss the relative benefits of exercise vs. diet in achieving and maintaining weight loss

• Discuss what types of exercise are most beneficial

• Learn how to risk-stratify obese patients

• Learn the components of treatment necessary for weight loss

Body Mass Index (BMI) is the global method of determining

overweight/obesity

BMI = wt/ht²(kg/m²)

(lbs/in²)x704.5

Definitions

• Normal: BMI 18 - 24.9• Overweight: 25 -29.9• Obese: >= 30

–Class I 30 - 34.9

–Class II 35 - 39.9

–Class III >= 40

Etiology of obesity

• Too much food intake

• Insufficient energy output– Not enough exercise– Low resting metabolic rate

• Genetic predisposition

• Environment favoring weight gain

• Psychological stressors

Obesity is associated with increased risk of co-morbid conditions:

• Hypertension• Dyslipidemia• Diabetes mellitus• Coronary artery dz.• Cerebrovascular dz.

• OVERALL MORTALITY HIGHER!

• Gallbladder dz.

• Sleep apnea

• Osteoarthritis

• Gout

• Cancers– Colon

– Breast

– Prostate

– Uterus

– Cervix

The scope of overweight/obesity

• 52% of US adults are overweight or obese!– ONE HALF!

• Prevalence is INCREASING!– 30% increase in adults in two decades– >80% increase in children/adolescents!!!

• Second-leading PREVENTABLE cause of death in the US

“Trends in overweight and physical activity among U.S. mlitary personnel,

1995-1998.”• 1995: 50% of military personnel overweight • 1998: 54% • Physical activity levels were high

– 67% engaging in regular, vigorous PA.

– Levels of PA Increased from 1995-1998

• CONCLUSION: the increase in Overweight is not due to decreased PA

• Lindquist CH, Bray RM. Prev Med 2001 Jan;32(1):57-65.

*

“Healthy Obesity”

• Physically-fit obese patients have LOWER mortality rates than unfit normal-weight persons!– Being thin doesn’t guarantee being healthy– Being fat doesn’t HAVE to be unhealthy

• Physical activity and cardiovascular fitness are much more predictive of health than body weight

Relative risk of all-cause mortality

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Despite the protection against cardiovascular dz. and all-cause mortality that cardio-respiratory fitness incurs, obesity still has its

problems.

• Osteoarthritis• Decreased quality of life• Social discrimination• Functional limitations

Facts on exercise in obesity tx.• Exercise alone only leads to slight wt loss, if any, but

marked reduction in mortality• Adding moderate/vigorous aerobic exercise to dieting

slightly increases wt loss• Aerobic exercise during wt loss lessens loss of FFM• Resistance exercise during wt loss preserves FFM and may

help maintain wt loss• Any type of exercise helps maintain wt loss, but duration

must be 4-10 hours/week• Compliance may be better with multiple short-bout sessions

How good is exercise alone for weight loss?

• Not very effective– 11 studies

• 5 found no change in weight w/ Exercise alone

• 6 showed slight weight loss w/ Exercise alone– 1-2 kg

*

Ross R et al. Reduction in obesity and related comorbid conditions after diet-induced weight loss or exercise-induced weight loss in men. A randomized, controlled trial. Ann Intern

Med 2000 Jul 133(2):92-103

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How much does exercise combined with diet add to weight

loss?• Not very much

– 15 studies• only 4 showed increased weight loss w/

addition of exercise to diet– Exercise may, however, help people pay more

attention to their diets

“A meta-analysis of the past 25 years of weight loss research using diet, exercise,

or diet plus exercise intervention.” • Average 15-week treatment

– Diet or Diet-plus-exercise program, produces a weight loss of about 11 kg

– Miller WC, Koceja DM, Hamilton EJ. Int J Obs Relat Metab Disord 1998 Aug;22(8):825.

What is the effect of exercise intensity on weight loss?

• Not much– as long as it is moderate to high

*

“Relationship between physical activity and body fat in women.”

• Irwin ML et al. Presented at 2001 ACSM Conference, Baltimore.

• 143 women • BMI and waist circumference were significantly related

to:– Moderate PA– Vigorous PA– Sports/conditioning– Occupation PA– (but not to walking or household/yardwork)

Are multiple, short-duration bouts as good as continuous exercise for

weight loss?

• Data inconclusive– Two studies suggest so.– More enjoyable + More accessible =

Better compliance– One study suggests no difference

Jakicic JM et al. Effects of intermittent exercise and use of home exercise equipment on adherence,

weight loss, and fitness in overweight women: a randomized trial. JAMA 1999 Oct;282(16):1554-60.

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“The effects of 18 months of intermittent vs. continuous exercise on aerobic capacity, body

weight and composition, and metabolic fitness in previously sedentary, moderately obese females.”

• Two exercise groups:– continuous (30 min, 3d/wk, 60-75% VO2max)

– intermittent (brisk walking 15 min 2x/day, 5d/wk).

• Weight loss:– continuous group: -2.1%

– intermittent group: none

• Donnelly JE at al. Int J Obes Relat Metab Disord 2000 May;24(5):566-72.

What is effect of resistance exercise on weight loss?

• None

• Some studies even show weight gain

• However, there may be some other benefits (stay tuned)

Does aerobic exercise vs. diet alone alter the composition of

weight loss?• YES

– Diet alone leads to marked reduction in fat free mass (FFM) as well as fat mass

– 7 of 10 studies: aerobic exercise preserves (FFM)

– Differences could be related to degree of obesity

• Higher BMI --> less FFM lost

Does exercise intensity affect body composition?

• Inadequately studied

What is the effect of resistance training on body composition?

• Definitely preserves, and may even increase, FFM

• Unclear effect on fat mass– 3 studies show more fat mass lost w/ Diet +

Resistance vs. Diet alone– 3 studies show no difference

What role does exercise have in weight loss maintenance?

• An important role• Wing RR. Med Sci Sports Exer 1999

– Review of literature; 6 studies • 4 of 8: significant long term differences favoring

diet + exercise

• 4 of 8: trend favoring diet + exercise

*

“Behavioral strategies of individuals who have maintained long-term weight

losses.”• Phone survey of 238 pts who lost >10% body wt

Factors that correlated with maintenance:– Higher levels of exercise, especially strenuous

– More behavioral strategies to control dietary fat intake

– Greater frequency of self-weighing

• McGuire MT et al. Obes Res 1999 Jul;7(4):334-41.

How much exercise is needed for optimal weight loss

maintenance?• The more, the better!

– 210 min/week brisk walking: 40% wt regain– 600 min/week brisk walking: 15% retain

What type of exercise is best for weight loss maintenance?

• Either aerobic or resistance

• ? Both?

Resistance exercise DURING weight loss may have a role in long-term

maintenance.• RCT, 20 kids/adolescents, 2 groups, 12 weeks

– Diet-only

– Diet + Resistance Exercise

• Weight loss equal in both groups

• Fat free mass decreased in diet-only group

• At one year f/u, wt regain inversely related with fat free mass at 12 wks

– Schwingshandl J et al. Effect of an individualised training programme during weight reduction on body composition: a randomised trial. Arch Dis Child 1999 Nov;81(5):426-8.

Response of obesity to exercise may have a genetic component.

• Study of obese patients in France • UCP3 gene

– Wild C/C genotype: BMI was negatively a/w PA (p=.015).

– C-->T polymorphism: BMI not a/w PA

– Otabe S et al. A genetic variation in the 5' flanking region of the UCP3 gene is associated with body mass index in humans in interaction with physical activity. Diabetologia 2000 Feb;43(2):245-9.

Risk-stratifying obese patients

• HIGH RISK– Coronary artery dz

– Sleep apnea

– Type 2 diabetes

• RISK FACTORS– Age (men>45, W>55)– HTN– LDL > 160– HDL < 35– Impaired fasting gluc– FH of premature CAD– Osteoarthritis– Gallstones– Stress incontinence– Smoking

Treating Obese patients

The undisputed, #1 BEST method of treatment for obesity

is...

(there is no one single best method)

Treating obesity demands a multi-faceted approach with chronic monitoring

1. Decreased caloric intake

2. Increased exercise

3. Behavioral modification

4. +/- Pharmacotherapy

5. +/- Surgery

Behavior modification strategies, extended treatment, and physical activity are excellent predictors of weight loss during treatment.

Foreyt JP, Goodrick GK. Evidence for success of behavior modification in weight loss and control. Annals of Internal Medicine 1993;119:698-701.

Goals of treatment

• Get patients to look like models?– NOT

• Get patients to their ideal body weight?– NOT practical usually

• Get patients to lose 5-10% of body weight?– HOPEFULLY

• Get patients to exercise and reduce their mortality risk?– DEFINITELY!

Set reasonable expectations

• Gradually develop regular exercise

• Gradually develop more healthy eating

• Shoot for losing 5-10% of body weight first

Why the not-so-lofty goals?

• Rarely do obese patients achieve ideal wt

• Falling short of lofty goals (SO common) leaves patients disappointed and highly susceptible to re-gain of weight lost

• Health can be achieved WHILE still obese– “Healthy obesity” concept

1. Decreased caloric intake

• 500 - 1000 kcal/day less than usual– Lose 1-2 lbs/week

• Women: 1000 - 1200 kcal/day total diet

• Men: 1200 - 1500 kcal/day total diet

National Heart, Lung, and Blood Institute. Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults: the evidence report. 1998.

2. Increased exercise

• Exercise regularly– Need to gradually work up to this– Start with brisk walking 10-45 min, 3-5

days/week– Work up to 60-80 min, most or all days/week– Aim to expend 1,000 - 2,000 kcal/week

NHLBI, ACSM

What kind of exercise is best for obesity treatment?

• May be a combination of aerobic AND resistance training

*

Kraemer WJ et al. Influence of exercise training on physiological and performance changes with weight loss in

men. Med Sci Sports Exer 1999 Sep;31(9):1320-9.

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Diet Only Diet &Aerobics

Diet, Aerobics,Resistance

Wt LossFat-Free MassStrengthAnaerobic PowerVO2max

Counseling patients to increase exercise (cont.)

• Use the 5 A’s of counseling:\– Address the agenda– Assess

• Knowledge, beliefs, concerns, feelings, stage of change

– Advise• Personalized exercise recommendations

– Assist• Provide support, identify barriers and resources

– Arrange follow-up

Tailor counseling to the patient’s stage of change

• Pre-contemplation - not remotely interested

• Contemplation - considering wt loss

• Preparation - starting to make small changes

• Action - meeting behavior change criteria

• Maintenance - steady behavior over time

Example: Counseling a Pre-contemplator

• Provide handout on health benefits of weight loss and exercise

• Discuss barriers to exercise

Example: Counseling a patient in

preparation phase

• Give specific advice on Frequency, Intensity, Time and Type of exercise (FITT)

Specific Exercise Recommendations:

FITT

• Frequency: most/all days of week

• Intensity: 55-90% of max heart rate

• Time: 30-80 minutes– Gradually work up to this– Start with brisk walking 10 min, 3-5 days/week– Work up to 60-80 min, most or all days/week

• Type: aerobic, resistanceNHLBI, ACSM

Follow-up after initial counseling

• See patient two weeks later and every month

• Ask about progress– Encourage!

• Ask about barriers– Discuss remedies

• Weigh patient

• Follow cholesterol, blood sugar, BP, etc.

“Prevalence of leisure-time physical activity among overweight adults--

United States, 1998.”

• Two thirds of overweight persons trying to lose weight reported using physical activity as a strategy for wt loss

• However, only 1/5 reported being active at recommended levels (30 min/day,most days).

– MMWR 2000 Apr;49(15):326-30.

3. Behavioral Modification

• Self-monitoring

• Stimulus control

• Body image and self-esteem counseling

• Stress management

• Social support

Self-monitoring

• One of the MOST HELPFUL TOOLS IN OBESITY MANAGEMENT

• Observation and recording of behaviors– Total calorie intake, fat grams consumed, food

groups used, situations that promote overeating, amount/intensity of exercise, weight, body composition, etc.

• Provides patient objective feedback so improvements can be made

Stimulus control

• Identifying and modifying the environmental cues that are a/w overeating and inactivity– Laying workout clothes on bed to increase

likelihood of exercise the next AM– Eating only at kitchen table– Avoiding situations where overeating common

Body image and self-esteem counseling

• Many obese pts have poor self-esteem– Negative thoughts lead to poor compliance

• Many have unrealistic wt loss expectations– Ideal body wt vs. 5-10%

• Distorted body image– 20% of obese pts won’t exercise because they

feel too fat

Stress management

• Stress is a primary predictor of relapse and overeating

• Management techniques are VERY effective in obesity treatment

• Refer to mental health professionals if not skilled yourself

Social support

• Those with it have more success

• Friends

• Family

• Community-based groups– Health clubs, education courses, Weight

Watchers

• Church-related activities

4. Pharmacological therapy

• Candidates:– BMI 27-29.9 and + risk factor– BMI >=30

• Never use as sole therapy!!– Poor effectiveness– Poor long-term maintenance of wt loss

• Agents approved by FDA for long-term use

Sibutramine (Meridia)

• Blocks reuptake of norepi and serotonin

• Appetite suppressant, ? thermogenic

• Proven efficacy, even at one year of tx

• Improves TC, LDL, TG, HbA1c

• Side-effects:– Headache, elevated BP, insomnia, constipation,

dry mouth

• Cost: $80/month

Orlistat (Xenical)

• Decreases fat absorption by inhibiting lipase in intestine (not absorbed)

• Proven efficacy, even long-term

• Improves TC, LDL, TG, HbA1c, glucose)

• Side-effects mostly GI:– Oily spotting, flatus, fecal urgency/incontinence

• Worse after fat ingestion; can lead to less fat eaten

– Multi-vit with A/D/E/K recommended

• Cost: $110/month

5. Surgery for obesity

• For high-risk patients who have failed non-surgical therapy– BMI 35-39.9 w/ RF’s– BMI >= 40

• Produces longest wt loss maintenance of all treatment methods

• Significantly decreases mortality rate• Techniques: vertical gastric banding, gastric

bypass

Summary of treatment based on BMI and risk

• BMI 25-30, no RF: advise wt loss• BMI 27-29.9, >= 2 RF: treat, +/- meds• BMI 30-35: treat, +/- meds• BMI 35-39.9, no RF: treat, +/- meds• BMI 35-39.9, + RF: treat; +/- meds; consider

surgery• BMI >= 40: treat; +/- meds; consider surgery

Review pearls

• BMI > 30 defines obesity

• Risk-stratify patients based on co-morbidity

• Combined treatment with exercise, diet and behavior modification is most effective

• Set a reasonable goal of 5-10% wt loss

• Start exercise slowly; emphasize benefits even if it doesn’t result in wt loss

• Follow-up frequently and monitor

• Consider meds/surgery for high-risk patients

Facts on exercise in obesity tx.• Exercise alone only leads to slight weight loss, if any, but

marked reduction in mortality.• Adding moderate/vigorous aerobic exercise to dieting

slightly increases weight loss.• Aerobic exercise during weight loss lessens loss of FFM.• Resistance exercise during weight loss preserves FFM and

may help maintain wt loss.• Any type of exercise helps maintain weight loss, but

duration must be 4-10 hours/week.• Compliance may be better with multiple short-bout sessions.

Counseling patients to increase exercise

• Regularly discuss exercise with your patients (obese or not)

“A meta-analysis of the past 25 years of weight loss research using diet, exercise,

or diet plus exercise intervention.” • Average 15-week treatment

– Diet or Diet-plus-exercise program, produces a weight loss of about 11 kg

• Weight loss Maintenance after one year:– Diet only: 6.6 kg loss maintained– Diet-plus-exercise: 8.6 kg loss maintained loss

– Miller WC, Koceja DM, Hamilton EJ. Int J Obs Relat Metab Disord 1998 Aug;22(8):825.