Chapter 16 Exercise Prescriptions for Health and Fitness

1. Chapter 16Exercise Prescriptions for Health and Fitness EXERCISE PHYSIOLOGY Theory and Application to Fitness and Performance, 6th edition Scott K. Powers & Edward T. Howley Presentation revised and updated by Brian B. Parr, Ph.D. University of South Carolina Aiken

2. Introduction • Physical activity • Any form of muscular activity • Can reduce the risk of death from all causes • Physical inactivity is a primary risk factor for coronary heart disease • Physical fitness • Set of attributes that relate to ability to perform physical activity • Exercise • A subset of physical activity that is planned, with a goal of improving or maintain fitness

3. Prescription of Exercise: Dose-Response Relationship • The effect (response) of the amount of a drug (dose) • Potency • Relatively unimportant characteristic • Slope • How much change in effect comes from a change in dose • Maximal effect • Efficacy • Variability • Effect varies between and within individuals • Side effect • Adverse effect

4. The Relationship Between Dose of a Drug and Effect Figure 16.1

5. Pattern of Responses to Exercise • Acute response • Occur with one or several exercise bouts but do not improve further • Rapid responses • Benefits occur early and plateau • Linear • Gains are made continuously over time • Delayed • Occur only after weeks of training

6. Dose-Response • Exercise dose is usually characterized by: • Intensity • % VO2max • % maximal HR • RPE • Lactate threshold • Frequency • Number of times (or days) per week • Duration • Number of minutes • Total kcal expended • Type of activity • Resistance and endurance exercises

7. Dose-Response Relationship for Exercise Figure 16.2

8. Physical Activity and Health • The health benefits of physical activity • More related to total number of calories expended than exercise intensity • Benefits depend on baseline activity level • The ACSM/CDC recommendation: • “Every U.S. adult should accumulate thirty minutes or more of moderate-intensity (3-6 METs) physical activity on most, preferably all, days of the week.” • This is minimum for achieving health outcomes • Additional activity, including vigorous exercise, provides additional benefits

9. Dose-Response Relationship for Physical Activity and Health Benefit Figure 16.3

10. General Guidelines for Improving Fitness • Screening • Health status screening (PAR-Q) • Risk of cardiovascular complications is related to degree of pre-existing cardiac disease • Progression • Moderate-intensity walking (3-4 mph) • Then increase duration and/or intensity • Walkwalk/jogjog • Warm-up, stretch and cool-down, stretch • Light exercise and stretching performed at beginning and end of exercise session

11. Exercise Prescription for CRF • Frequency • 2–4 sessions per week • Gains level off after 3 to 4 sessions/week • Duration • Total work/session should 200-300 kcal • Must be considered with intensity • Intensity: • Describes the overload needed to bring about a training effect • 60%-80% of VO2max • Lower in those with low initial fitness level • Target heart rate range

12. Intensity, Duration, and Frequency of Exercise and VO2 Max Figure 16.4

13. Determining Target Heart Rate Range • Direct method • THR range determined from maximal GXT • HR at 60–80% VO2max • Indirect method • Heart rate reserve (Karvonen) method • Subtract resting HR from maximal HR to obtain HRR • Take 60% and 80% of HRR • Add each HRR to resting HRR to obtain THR range • Percentage of maximal HR • Take 70% and 85% of maximal HR as THR range • Use RPE scale in addition to HR • RPE of 12–16 is about 40/50–85% HRR

14. Target Heart Rate Range Determined From GXT Figure 16.5

15. VO2 Reserve (VO2R) • VO2 Reserve • Difference between VO2max and resting VO2 • %HRR more closely linked to %VO2R than %VO2max • Greater difference for those with low fitness level • Calculating target VO2 • Take 60% and 80% of VO2R

16. Sequence of Physical Activity • Walking • Start at a comfortable speed for 15 minutes • Gradually increase duration and speed • Jogging • Start by adding some running when walking • Gradually increase speed/duration of running • Games and sports • Intermittent higher-intensity activities within THR range

17. An Example of a Walking Program Table 16.1

18. An Example of a Jogging Program Table 16.2

19. Strength and Flexibility Training • Muscular strength and flexibility are important components of a complete fitness program • Recommendations • Dynamic resistance exercises • Full range of motion • 8-10 different exercises • 8-12 repetitions per exercise

20. Physical Activity Pyramid Figure 16.6

21. Strength Training • ACSM recommendation: • One set of 8–10 exercises • 8–12 reps per set • 2–3 sessions per week • Single vs. multiple sets • One set to achieve health and fitness goals in average individuals • Multiple sets for increasing strength in trained individuals • Maximal strength gains • 4–8 sets at 60–85% 1RM, 2–3 days per week

22. Environmental Concerns • Environmental conditions can alter exercise heart rate • Adjust exercise intensity in adverse environments • High temperature and humidity • Altitude • Use THR range as a guide for intensity