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Exercise Prescription for Cardiovascular

Fitness

The Art of Exercise Prescription

The art of exercise prescription is the successful integration of exercise science with behavioral techniques that result in long-term program compliance and attainment of the individual’s goals.

P 136 (ACSM’s Guidelines)

Components of Fitness

CardiorespiratoryResistance Exercise

Muscular StrengthMuscular Endurance

FlexibilityBody Composition

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MSSEVol 30, number 6

1998The Recommended Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory and Muscular Fitness and Flexibility in Healthy Adults

ACSM Position Stands

Definitions

Specificity – training effects derived from an exercise program are specific to the exercise performed, muscle groups involved, ROM and energy system utilizedOverload principle – for a tissue or organ to improve its function, it must be exposed to a stimulus greater than it is normally accustomed to

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Components of the Training Session

Warm-up (5-20 minutes)Purpose

Facilitates transition from rest to exerciseStretches postural musclesIncreases blood flow to working muscleElevates body temperatureIncrease joint ROMMay decrease susceptibility to musculoskeletal injuryMay decrease occurrence of ischemia and life-threatening arrhythmias

Warm-up

Protocol5-10 min of low-intensity exercise (10-30% HRR) gradually increasing in intensity to the lower limit of the exercise prescription5-10 min of static, dynamic, or PNF stretching

Stimulus or Conditioning Phase

PurposeImprove VO2maxReduce risk of CAD, diabetes, etc.

Protocol20-60 min of continuous or intermittent activity (multiple bouts of 10 minutes)Lower intensity – 30 min or more

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Cool-down

PurposeGradually decrease heart ratePrevent pooling of blood (muscle pump)Prevent post exercise hypotension -antihypertensivesCombats post exercise increase in plasma catecholamines reducing risk of serious arrhythmias

Cool-down

ProtocolGradually decrease in intensity for 5-10 min (muscle pump) - large muscle groupsStretching

Length of W-U and C-D?

Depends……….Time of dayTemperatureMedicationsRisk stratificationIntensity of work out

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Checking Heart Rate/RPE

When? End of warm-upReach steady state, not too late to adjustEnd of cool down

Heart rate still elevatedHot shower

Where monitor?

Carotid – problems at restBrachialRadialHand over chest (exercise only)

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How many seconds?

Rest – 30 – 60 secondsExercise

15 X 4 = 60 seconds10 X 6 = 60 seconds6 X 10 = 60 seconds

Issues

Accuracy – 15 second countDecrease Intensity – heart rate drops within 15 secondsTime to locate pulse10 second count for exercise

Start from 0 or 1?

0 - if timing is initiated simultaneously with a pulsation

1 - if a second person is keeping time or a lag between the initiation of timing and first pulsation

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Variables That Interact to Form Exercise

PrescriptionFrequencyIntensityTimeType of Activity

Type of Activity

Variety Exercise all major muscle groupsReduce risk (high-impact vs nonweight bearing) of injuryIncrease likelihood that training effect will transfer to vocational and recreational activities

Aerobic Activity

Extended timeRhythmic/repetitiveLarge muscle groups*

CWT ~ 6% increase in VO2max vs 20-25% for aerobic exercise program

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If target heart rates are equivalent during cardiorespiratory

endurance exercise and circuit weight training, why aren’t the training

effects the same (increase in VO2max)?

Pressor Response

Increase in SBP and DBPQ = HR X SV

HR increases with CDV and WTSV – NC or decrease with WT

Decreased preload (venous return due to compression of vena cava)Increased afterload (due to mechanical constriction of vessels) - increased TPR decreases EF or SV)

Box 7-1. Grouping of Cardiorespiratory Endurance

Activities (p 144 G)

Group 1 Activities that can be readily maintained at a constant intensity and interindividual variation in energy expenditure is relatively low. Desirable for more precise control of exercise intensity, as in the early stages of a rehabilitation program. Examples of these activities are walking and cycling, especially treadmill and cycle ergometry

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Box 7-1. Grouping of Cardiorespiratory Endurance

Activities ContinuedGroup 2 Activities in which the rate of energy

expenditure is highly related to skill, but for a given individual can provide a constant intensity. Such activities may also be useful in early stages of conditioning, but individual skill levels must be considered. Examples include swimming and cross-country skiing

Box 7-1. Grouping of Cardiorespiratory Endurance

Activities ContinuedGroup 3 Activities where both skill and

intensity of exercise are highly variable. Such activities can be very useful to provide group interaction and variety in exercise, but must be cautiously employed for high-risk, low-fit, and/or symptomatic individuals. Competitive factors must also be considered and minimized. Examples of these activities are racquet sports and basketball

Determining Exercise Intensityp 145 G

Individual’s level of fitness: low fit, very sedentary and clinical populations can improve fitness with lower-intensity, longer- duration exercise sessions. Higher fit individuals need to work at the higher end of the intensity continuum to improve and maintain their fitnessMedications (see Appendix A) that may influence HR require special attention when defining the initial target HR range and when the dose or timing is changed

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Exercise Intensity Continued

Risk of cardiovascular and orthopedic injuries is higher and adherence is lower with higher-intensity exercise programsIndividual preferences for exercise must be considered to improve the likelihood that the individual will adhere to the exercise program Individual program objectives (lower BP; lower body fatness; increased VO2max) help define the characteristics of the exercise prescription

Time

20-60 min of continuous or intermittent exerciseMinimum of 10 min boutsMost train 20-30 min 70-85% HRmax or 60-80% HRR, not counting WU and CDRelated to caloric expenditure goals

Incidence of Injury and Time

15 min - 22%30 min – 24%45 min – 54%****

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Frequency

Deconditioned – can improve with 2 d/wkOptimal – 3-5 d/wk>3 d/wk – magnitude of change is smaller

Exercise at Lower Intensities

> 3 d/wk required to achieve adequate caloric expenditure in novice population 150-400 kcal/day in PA or Exercise~ 1,000 kcal/wk as initial goal for sedentaryGoal = 300-400 kcal/d of PA

If < 5MET functional capacity1-2 short daily sessions

Incidence of Injury(Pollock et al.)

1 d/wk – 0%3 d/wk – 12%5 d/wk – 39%*********

If 60-80% HRR or 70-85% HRmax – 3 days adequate to improve or maintain VO2max

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Bottom Line

> 30 min, 3 d/wk significantly increases risk of injury

Transfer of Training Benefits (ACSM G p 157)

Mode of Activity

Specificity – little transfer between arm and leg work with regard to submaximal or maximal exerciseAlso applies to lactate threshold and pulmonary ventilationCentral vs peripheral changes

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Fick EquationVO2 = HR X SV X a-v O2dif

CentralIncrease in SVIncrease in Q at max

PeripheralIncrease a-v O2dif

Increase number of capillariesIncrease mitochondrial enzymesIncrease number of mitochondriaIncreased myoglobin

Mode of Activity

Maximal heart rates will be different with different modes of activityRPE values will be specific to mode of exerciseCross training

Muscle balanceRisk of injuryVariety

Supervision?

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Exercise for Weight Loss

Rest – 1.2 kcal/min65% fat/35% CHOEnergy system - aerobic

Intensity and Substrate Utilization with Exercise

IntensityCHO UtilizationFat Utilization

Training Status

Cardiorespiratory fitness – burn more fat and less CHO for a given workload

Why????More mitochondria

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Diet and Substrate Utilization

Eat CHO within 8 hr of exerciseFat utilization CHO utilization

Fasting – burn greater %age of fats vs CHO

Questions

Is it better to exercise at a low intensity which burns more fats or a higher intensity which burns more CHO if weight loss is my primary goal?

The facts about fat(Stanforth, UTA)

50% VO2max50% fat/50% CHO4.86 kcal/min146 total kcal for 30 minFat – 73 kcalCHO – 73 kcal

70% VO2max40% fat/60% CHO6.86 kcal/min206 total kcal for 30 minFat – 82 kcalCHO – 124 kcal

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AnswerIf client can safely exercise for full exercise

period at the higher intensity – better for weight loss

Why?Burns more total kcalBurns more fat (even though %age fat higher due to more total kcal burned)Total kcal burned more important than kcal as fat or CHOGreater EPOC (>70% VO2max )

Which is better for weight loss if only 30-60

minutes?Both cardio and weight trainingStudies show that cardiovascular exercise is not adequate to maintain FFMEqually importantResistance training – burn more kcal post exercise for equivalent VO2 and more fat

Comparison of Weight Loss Options

Goal: 5 poundsExercise onlyDiet onlyDiet + ExerciseDiet + Exercise + Resistance Training

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Exercise Only

3 miles, 3 days/week3 mi X 100 kcal/mile X 3 day/wk = 900 kcal/wk3500 kcal/lb X 5 lb = 17,500 kcal17,500 kcal/900 kcal/wk = 19.4 wk

Diet Only

Decrease caloric intake 250 kcal/day250 kcal/day X 7 day/wk = 1,750 kcal/wk17,500 kcal/1750 kcal/wk = 10 weeks

Diet + Exercise

Diet 1,750 kcal/wk Exercise 900 kcal/wkTotal = 2,650 kcal/wk17,500 kcal/2,650 kcal/wk = 6.6 weeks

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Add Resistance Training

Add 2 pounds of muscle massBurn additional 35 kcal/day per lb of muscle35 kcal/day X 2 = 70 kcal/day 70 kcal/d X 7 d/wk = 490 kcal/wk490 + 2,650 (diet+exercise) = 3,140 kcal/wk17,500 kcal/3,140 kcal/wk = 5.3 weeks

What type of exercise is best for weight loss?

Aerobic ExerciseImprove healthImprove VO2maxBurns more kcal (10-13 kcal/min)

What type of exercise is best for weight loss?

Resistance TrainingIncrease/preserve muscle massIncrease bone densityMuscle is more metabolically active than fat (burns more kcal)Increase muscular strength and enduranceHormonal response favors higher post exercise oxygen consumption than endurance aerobic conditioning and fat burning

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Bottom Line

Both are important!

Research on role of weight training and weight lossNot shown a definitive benefit alone or in combination with endurance exercise Reductions in FFM = Decrease in REENo scientific evidence

Criteria for Overweight/Obesity

55-60% Adults Overweight (BMI > 25kg/m2) Of this group 20-25% Adults Obese (BMI > 30 kg/m2)Pattern of body fat distribution – android (apple) vs gynoid (pear)Intra-abdominal fatness positively associated with hypertension, hypercholesterolemia and hyperinsulinemia

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Energy Deficit

500-1,000 kcal/dayGoal – 1-2 pounds/weekReduce fat and kcal both for best resultsMaintenance of low fat intake important for maintenance of long-term weight loss

Summary

BMI >25 should reduce weightReduce weight by minimum of 5-10%Long-term weight maintenance goalMaintenance – body weight within 5 pounds of current weightChange eating and exercise behaviorsReduce intake 500-1,000 kcal/d

SummaryFat <30% of energy intakeMinimum of 150 min/wk of moderate intensity – activity goalLong-term weight loss - 200-300 min/wk or >2,000 kcal/wk of activityResistance training Pharmacotherapy only for BMI > 30 or > 27 with comorbiditiesBehavioral intervention

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Intensity and Heart Rate

Intensity/type Heart Rate (bpm)

% Max HR % VO2max

High intensity high impact

175 88 78

High intensity low impact

163 83 61

Low intensity high impact

164 82 67

Low intensity low impact

130 65 37

Ways to Increase Intensity (VO2)

Intensity/Type VO2 (ml/kgmin)

Heart Rate (bpm)

Kcal/min

Low Impact Aerobics 39.5 173

10.7

High Impact Aerobics 39.4

170 10.6

How do you increase HR and VO2?

Propulsion (change center of gravity)JumpBenchAs move

LocomotionChange directionsLengthen lever armArms???????

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Bench Height vs Step Rate(VO2 ml/kgmin)

Bench Height (inches)

Step Rate (bpm)

6 8 10 12

120 21.3 25.9 29.8 34.1

128 22.6 27.1 31.6 36.0

Body Position and Energy Cost on Stairmaster (METs)

WorkloadLevel

5 7 9 11

No support 7.3 9.1 10.8 12.4

Arm Support

6.4 7.8 9.1 10.3

Lean 6.2 7.4 8.9 10.1