KSU

Exercise Prescription

for the Obese Patient

Hazzaa M. Al-Hazzaa, Ph D, FACSM

Professor & Director,

Exercise Physiology Laboratory, and

Scientific Board, Obesity Research ChairKing Saud University

http://faculty.ksu.edu.sa/hazzaa

International Obesity Congress, Riyadh, March, 2011

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Workshop Outlines

Basic concepts in physical activity.

Energy balance equation and where PA fits.

General principles in exercise prescription.

Physical activity prescription for the obese.

Metabolic calculations in physical activity.

Case study presentations.

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Basic Concepts

In

Physical Activity

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Definitions

Any bodily movement produced by the skeletal muscles resulting in energy expenditure above resting state.

Physical Activity

Physical Fitness

A set of attributes that people have or achieve, which relates to the ability to perform physical activity.

Caspersen, et al., Public health Rep,1985

1

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Definitions

The amount of energy expended during exercise relative to the energy expenditure during rest.

Metabolic Equivalent (MET)

Energy expenditure during rest = 1 MET

= 3.5 ml of O2 / kg. min

= 1 kcal / kg. hr

2

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Physical Activity Intensity in MET

Light: Less than 3 MET

Moderate: 3 – < 6 MET

Vigorous: > 6 MET

CDC, 1996

Classification of Exercise

Aerobic exercise: Endurance type exercise, rhythmic, sustained for sometimes. Example: Walking, jogging, running, cycling, swimming, etc…

Strength (Resistance) exercise:Weight training with free weight, machine, elastic rope, calisthenics, etc…

Flexibility exercise:Stretching exercise.

Balance exercise for the Elderly

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Moderate & Vigorous Intensity

Physical Activities

Moderate:

Brisk walking, Recreational swimming, Volleyball, Slow aerobics, Moderate cycling Gardening, Tennis-double, Badminton etc..

Vigorous:

Jogging, Running, Tennis-single, Basketball, Rope skipping, Squash, Fast aerobics, Fast cycling, Stepping, Soccer, etc

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What is the Amount of Physical Activity

that Promotes Optimal Health?

Moderate Intensity Physical Activity.

Energy Expenditure = 3 - < 6 MET

That is: ≥ 30 min/day, ≥ 5 days/week.

≥ 150 min. per week.ACSM, 2000; CDC, 1996

≥ 1000 k. calories/week.

Drygas, et al., 2000; Fletcher, et al., 1996; Lee, et al., 2000

What is the Amount of Physical Activity

Needed for Weight Loss?

Moderate-Intensity Physical Activity.

Energy Expenditure = 3 - < 6 METs

250-300 min. per week.

≥ 2000 k. calories/week.

ACSM Position Stand on “Appropriate Physical Activity Intervention Strategies for Weight Loss and Prevention of

Weight Regain for Adults”, Med Sci Sports Exerc, 2009.

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BMR

Thermal Effect of Food

Physical Activity

Dietary intake

الطعام المتناول

األيض القاعدي

طاقة هضن الطعام

النشاط البدني

الطاقة المصروفةEnergy Expenditure

المتناولةالطاقة Energy Intake

Elements of Energy Balance

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Components of Energy Expenditure

Basal Metabolic Rate

(60-70%)

Thermal Effect of Food (10%)

Physical Activity (20-30%)

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Graded Exercise Testing

It is recommended before any moderate to

high intensity exercise, especially if:

Age is > 40 yrs.

With diabetes for > 10 yrs duration.

Presence of any CHD risk factors.

Presence of peripheral vascular disease.

ACSM's Guidelines, 2000

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Evaluation of a Person’s Readiness

to engage in Physical Activity

PAR-Q

The Flow Charts Approach

Evaluation of Person’s Readiness to Physical Activity

No

Does the person have symptom of CV

disease? **

Yes

Does the person have diagnosed disease? *

No Yes

Consider GXT and cardiology referral

Does the person have more than one risk

factor? ***

Yes Moderate activity is safe; vigorous activity:

should have GXT

No

Is Age over 40 yrs for

Men and over 50 yrs for

women

No

Moderate or vigorous activity is safe

Yes

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Readiness to Physical Activity (continued)

* Diagnosed Disease:

Cardiac disease (excluding controlled

hypertension)

Pulmonary Disease

Metabolic disease

** Symptom of CV disease:

Pain or discomfort in the chest,

arms suggestive of ischemia

Shortness of breath at rest or

with exertion

Dizziness or syncope

Orthopnea or paroxysmal

nocturnal Dyspnea

Ankle edema

Palpitations or unexplained

tachycardia

Intermittent claudication

Known heart murmur

Unusual extreme fatigue

*** Risk factors:

Family history

Tobacco Use

Hypertension

Hyperlipidemia

Diabetes Mellitus

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Principles of

Exercise

Prescription

KSUACSM, 2000

Health-Related Dimensions of Physical Activity

أبعاد النشاط البدني المعزز للصحة

.(Caloric Expenditure)الطاقة المصروفة •

.(Aerobic Intensity)األنشطة الهوائية المرتفعة الشدة •

.(Muscular Strength)القوة العضلية •

.(Flexibility)المرونة •

األنشطة البدنية التي يتم فيها حمل الجسم • (Weight-bearing physical activity).

Caspersen, et al., 1998

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Dimensions of health-enhancing Physical Activity

Energy Expenditure

CHD Diabetes Obesity

Moderate Intensity Aerobic Activity:

Walking, Swimming, Cycling, Badminton, tennis-

double, Daily living physical activity (taking

stairs, working at home, gardening, etc..)

Components of Exercise Prescription

Mode (Type of exercise)

Duration

Frequency

Intensity

Progression of Exercise Program

Safety/precaution

ACSM, 2000

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Progression

First, increase the frequency of physical

activity.

Then, increase the duration of physical

activity.

Lastly, increase the intensity of physical

activity.

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Components of an Exercise Session

Warm-up

period

5-10 min

Cool down

period

5-10 min

Exercise

period

30-60 min

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Why Cool Down?

Allows gradual recovery of heart, lungs and blood

pressure to resting state.

Maintain adequate venous return to reduce post

exercise dizziness

Reduce lactic acid and muscle soreness

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Exercise

Prescription

for Obese Patient

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Reduces as much of the FFM loss.

Decreases body fat.

For morbidly obese, enhances the ability to carry on the Activity of Daily Living.

Goals of Exercise Prescription in Obesity

Improves chronic disease risk factor profile.

Enhances functional capacity.

Improves cardiorespiratory fitness.

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Exercise Prescription in Obesity 1/3

Low impact moderate-intensity aerobic activity

(walking, cycling, swimming, recumbent exercise).

Gradually increase exercise duration to reach

60 min. each day.

Exercise duration and frequency are more

important than intensity of exercise.

Gradually increase exercise frequency to

reach 5 days or more each week.

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Exercise Prescription in Obesity 2/3

Avoid jogging and running. It stresses knee,

hip and ankle joints.

For those with feet problems, Alternate

between walking, swimming, and cycling.

Exercise session should include 5-10 min. of

warm-up and a 5 min of cool-down.

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Exercise Prescription in Obesity 3/3

Use proper shoes, with silica gel or air-filled

soles, to absorb shocks.

Avoid dehydration by keeping the body

always hydrated.

Moderate intensity weight training program is

recommended to improve muscle strength and

preserve lean mass (8-12 repetitions 2 times /week).

What is the Potential influence of Resistance Training on Energy Expenditure?

Jakicic J, et al. Med Sci Sports Exerc, 2001, 33: 2145-2156

Resistance

Training

Muscle

MassRMR

Total Energy

Expenditure

Body

Fat

Free Living PA

Fat Oxidation

Muscle mass has an energy requirement of about 15-25 kcal/kg. day (Sparti A, et al. Metabolism 1997; 46: 1225-1230).

Resistance Training Is Important for reducing the Loss of FFM due to Bariatric Surgery

Systematic Review

Chaston T, et al. Int J Obesity, 2007, 31: 743-750

Roux en Y gastric bypass

(RYGB)

Laparoscopic adjustable

gastric banding (LAGB)

31 % 18 %

Exercise Prescription for the Morbid Obese patients

This obese patient has a limited ability to perform physical activity, especially weight-bearing activity.

During Walking:

They have shorter step length.

Slow self-selected walking pace.

During Bicycling:

They are less efficient when doing exercise, even during unloaded cycling.

Wasserman et al., 1999, p. 69

Obesity Upward displacement of VO2 relative to work load

Rest

VO2

Normal

Unloaded cycling

Increased work load

3 6 9 120

Obese

A Guide to Selecting Treatment for Obesity

TreatmentBMI Category

25–26.9 27–29.9 30-34.9 35–39.9 ≥ 40

Diet, PA and

behavior

therapy

With

Comorbidities

With

Comorbidities + + +

Pharmaco-

therapy

With

Comorbidities + + +

SurgeryWith Comorbidities

Consider pharmacotherapy only if a patient has not lost 1/2 kg per week

after 6 months of combined lifestyle therapy.

From: Identification, Evaluation, and Treatment of Overweight and Obesity

in Adults – NHLBI, 2000.

Exercise Prescription before and after Bariatric Surgery

Pre-Op:

Start exercise prior surgery.

Individualized exercise plan.

Post Surgery- Day 1:

Sit in chair with assistance and walk in room 2-3 times.

Post Surgery- Day 2- Day 7:

Walk 3-5 min , 4- 6 times a day.

Adapted from: The Centennial Center for the Treatment of Obesity, Nashville, Tennessee

1

Exercise Prescription before and after Bariatric Surgery

Post Surgery- Month 1 and on:

Walk 30 min to 1 hour , at least 5 times a day.

May begin weight training with doctor approval.

Adapted from: The Centennial Center for the Treatment of Obesity, Nashville, Tennessee

2

Post Surgery- Week 1 to Week 2:

Continue walking while increasing walking time to 5-15 min , 3 times per day.

Post Surgery- Week 2 to Week 4:

Continue walking while increasing walking time to 10-15 min , 3 times per day.

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Exercise &

Weight Control_________________________________________________

Practical

Consideration

Calculation of Exercise Intensity

Using percentage of oxygen uptake reserve

(%VO2R) or heart rate reserve (%HRR).

Using percentage of maximal heart rate (% HR max)

or maximal oxygen uptake (%VO2 max).

Using MET value (3-5.9 METs is moderate).

Using RPE scale(11-13).

% of Heart

Rate Reserve

% of Maximal

Heart Rate

Exercise

Intensity

< 20 %< 50 %Very Light

20 – 39 %50 – 63 %Light

40 – 59 %64 – 76 %Moderate

60 – 84 %77 – 93 %Hard

84 % >93 % >Very Hard

100 %100 %Maximal

Classification of Exercise Intensity

Howley, MSSE (Suppl) 2001; (6): S 367.

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Calculation of Exercise Intensity

Maximal Heart Rate = 208 – ( 0.7 X age (yrs))*

Maximal Heart Rate = 220 – age (yrs))

Heart Rate Reserve = HR max – HR rest

% of Maximal Heart Rate % of Heart Rate Reserve or

* Tanaka, et al, 2000

KSUACSM, 2000

Patients using Beta Blockers

Previous equations are not

suitable for them. Drugs

affecting Beta receptors lower

heart rate at rest, submaximal &

maximal exercise.

20

40

60

80

100

120

140

160

180

200

Rest 25 50 75 100

No BlockadeParasympathetic blockadeSympathetic blockade

Astrand & Rodahl,1977, p. 191 ( Data: Ekblom et al., 1972

% of Maximal Oxygen Uptake

Propranolol

Effects of Sympathetic and

Parasympathetic Blockades on H. R.

Atropine

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Exercise prescription using VO2R

If a patient has a 17.5 ml/kg.min VO2 max,

prescribe an exercise intensity for him at 50%

of his VO2 R?

VO2 R = VO2 max – VO2 rest

= 17.5 - 3.5 = 14 ml/kg.min

50 % of VO2 R = 14.0 x 0.50 = 7 ml/kg.min

Required exercise intensity =

7 + 3.5 = 10.5 ml/kg.min ( 3 METs)

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Energy Calculation

during

Physical Activity

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Recommended Weight Loss Program

1 kg per week = 7700 k. calories/ week.

A combination of Diet and Exercise

(Brisk Walking)

Exercise: 15-25% of total energy deficit

1200-2000 k. cal./week

* National Institute of Health Guidelines, 1998

0.5 – 1.0 kg per week *

CalorieActivity

0.07Brisk walking

0.13Running (7.5 min per km)

0.208Running (5 min per km)

0.162Swimming

0.162Rope skipping (70/min)

0.165Rope skipping (80/min)

0.097Badminton

0.109Tennis

0.212Squash

0.138Basketball

Energy Cost of Physical Activity(k. calorie/kg. min)

McArdle, et al. 1991

METActivity

2.5Walking (slow)

4Walking (Brisk)

8Running (7.5 min per km)

6Swimming

8Rope skipping (slow)

6Weight training

4.5Badminton

8Tennis (single)

12Squash

8Basketball

Energy Cost of Physical Activity in MET

Ainsworth, et., 2000Ainsworth, et al., Compendium of physical activity. MSSE, 2000

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Calculating Energy Expenditure per week

ACSM’s Guidelines, 2000

Energy expenditure in K. Calorie/week =

(MET * Activity time (hours) * Frequency

per week * body wt

(4 * 1 * 5 * 80) = 1600 k. cal./min

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Converting MET to kilocalorie

ACSM’s Guidelines, 2000

Energy expenditure in K. Calorie/min =

(MET * 3.5 * body wt) / 200

(4 * 3.5 * 80) / 200 = 5.6 k. cal./min

5.6 * 60 min * 5 times per wk = 1680 k.cal/week

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How to Calculate

Energy Expenditure

during Brisk Walking!

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= 0.07 k. calorie per kg of body weight /min.

Energy Expenditure during Brisk Walking

An Example:

a person weighing 76 kg would expend:

0.07 X 76 = 5.3 k. calorie per min.

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Energy Expenditure during Brisk Walking

If that person has to expend 1200 k.calories

per week. HOW much time he/she should walk

per week?

1200 / 5.3 = 226.4 min.

= 45 min/ 5 days per week, or

= 57 min/ 4 days per week.

Note: This includes resting energy expenditure

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Case Study 1 (Q-1)

An obese women, 38 years of age, her weight = 94

kg, & height = 172 cm. She has high BP and has pre

diabetes. Nothing else remarkable.

Prescribe a physical activity program for her, so she

could increase her energy expenditure through

brisk walking by 1400 K. calories per week.

Will this increase in her activity is enough to reduce

her weight as well as to improve her CHD risk

factors?

Case Study 1 (A-1)

Brisk walking energy expenditure = 0.07

kcal/min or 4 METs.

Time needed = 1400 / 6.6 = 212.1 minutes/ week

212.1 / 5 = 42.4 min.

Energy cost of walking = 94 * 0.07 = 6.6 k cal. min.

Energy cost of brisk walking = (MET * 3.5 * weight) /200

= (4 * 3.5 * 94) / 200 = 6.6 k. calorie/ min.

Case Study 1 (A-2) continued

Net MET = 4-1 = 3

Energy cost of brisk walking = (MET * 3.5 * weight) /200

= (3 * 3.5 * 94) / 200 = 5 k. calorie/ min.

Time needed = 1400 / 5 = 280 minutes/ week

280 / 5 = 56 min.

Case Study 2 (Q-1)

An obese man, 48 years of age, his weight = 90 kg,

& height = 170 cm. He is hypertensive and has

diabetes. He also suffers from moderate pain in his

knee (osteoarthritis).

Prescribe a physical activity program for him, so

he could reduce his weight as well as to improve

his blood sugar control and hypertension,

assuming an energy expenditure from physical

activity of 1600 K. calories per week?

Case Study 2 (Q-2) continued

In his case, what is the right type of physical

activity?

If his target body weight is 75 kg, and assuming

that 25% of the energy deficit can come from

increased energy expenditure through physical

activity, how many weeks needed for him to loose

those 15 kg of excess body weight, through

exercise and diet?

Case Study 2 (A-1) continued

Energy cost of swimming = (MET * 3.5 * weight) / 200

= (6 * 3.5 * 90) / 200 = 9.4 k. calorie/ min.

Swimming, but he could alternate between

walking and swimming.

Time needed = 1600 / 9.4 = 170.2 minutes/ week

170.2 / 5 = 34 min. OR 170.2 / 3 = 56.7 min.

Case Study 2 (Q-2) continued

In his case, what is the right type of physical

activity?

If his target body weight is 75 kg, and assuming

that 25% of the energy deficit can come from

increased energy expenditure through physical

activity, how many weeks needed for him to loose

these 15 kg of excess body weight, through

exercise and diet?

Case Study 2 (A-2) continued

Total excess energy = 15 * 7700 = 115,500 k. cal.

25% from exercise = 115,500 * 0.25 = 28875 k. cal.

Time needed = 28875 / 1600 = 18 weeks (4.2 months).

OR: 15 / 18 = 0.833 kg. per week.

Case Study 3 (Q)

An obese sedentary women, her age = 55 yrs,

weight = 80 kg, height = 152 cm.

She has type 2 diabetes for 6 years, and BP under

control with medication. Otherwise she is OK.

Prescribe diet and physical activity to reduce her

weight as well as to control her diabetes and

hypertension, targeting energy expenditure with

exercise of 1400 K. calories per week?

Assuming a target body wt. of 60 kg, what is her

daily energy needs (requirement)?

Case Study 3 (A-1)

BMI = 80/ (1.52 * 1.52) = 34.6 kg/m2

Brisk Walking: 0.07 K. calorie/kg. min.

Energy cost of walking = 80 * 0.07 = 5.6 k cal. min.

Time needed to expend 1400 k. cal. Per week =

1400/ 5.6 = 250 minutes;

250/5 days = 50 min. per day

OR approx. 63 min a day for 4 days per week

Estimated Energy Requirement (EER)

(K. Calorie/day)

Adult Males = 662 – (9.53 * Age) + Physical activity level *

(15.91 * weight + 539.6 * height)

Adult Females = 354 – (6.91 * Age) + Physical activity level *

(9.36 * weight + 726 * height)

Age in years;

Weight in kg;

Height in meter;

Physical activity levels are shown in the next table.

Add 10 K. cal. in male and 7 K. cal in female for each year less than 30 years,

and subtract the same for each year above 30 years.

From: IOM Dietary Reference intake Macronutrients report, 2002

Physical Activity LevelGender

ActiveLow ActiveSedentary

1.311.161.0Males 19 yrs &

above

1.271.121.0Females 19 yrs &

above

Physical activity Coefficients

Sedentary: Does not do any activity at all.

Low Active: Daily moderate activity for30 min.

Active: Daily moderate activity for 60 min or more.

From: IOM Dietary Reference intake Macronutrients report, 2002

Case Study 3 (A-2) continued

EER = 354 – (6.91 * 55) + 1 * (9.36 * 60 + 726 * 1.52)

EER = 354 – (380.1) + 1 * (561.6 + 1103.5) = 1691.2

EER = 1691.2 – (25 *7) = 1516.2 K. calorie/day

Estimated Energy Requirement

Active:

EER = 354 – (6.91 * 55) + 1.27 * (9.36 * 60 + 726 * 1.52)

EER = 1965.8 K. calorie/day