Health Psychology Chapter 16: Exercising

1. Health PsychologyChapter 16: Exercising Mansfield University Dr. Craig, Instructor

2. Exercise & Physical Activity • Less than 1/4 of population engaged in regular forms of vigorous physical activity/exercise of any kind • Surgeon General - lack of physical activity is a primary risk factor for CV disease • How much is exercise or physical activity is enough? • Early- 20 min @50-85% of THR, 4-5 days • Revision- 30 of moderate physical activity on most days • Distinctions and implication of revision

3. Kinds of Exercise: “Building muscles” • What kinds of exercise/p.a. are helpful? • Isometric exercise • pushing against unmovable object to gain strength • little joint movement (often ideal for elderly or those with ROM problems • Isotonic- contraction of muscles against weight • free weightlifting • builds muscles strength and endurance • Isokinetic- • nautilus • constant weight during contraction throughout ROM • superior muscle endurance, reduced injury

4. Kinds of Exercise: Aerobics & Anaerobics • Anaerobic exercise • short intense bursts of work requiring no oxygen for energy production • speed events, include many activity requiring maximal effort over between 1 and about 45 seconds • improves muscle strength and some endurance • Aerobic Exercise • exercise of extended duration (at least 12-20 minutes [note]) requiring low to moderate intensity • dependent on oxygen metabolism for energy production • important in development of CR fitness (O2 delivery)

5. What does it mean to be “Fit”? • Organic (Genetic) fitness vs. Dynamic (acquired) Fitness • Muscle Strength (contraction strength/force) & Endurance (Repetition)- • importance? • Flexibility- range of motion (ROM) • importance? • Aerobic Fitness- • increased O2 delivery and metabolism during exercise • blood flow increases • mitochondrial concentration and vascularization at muscle level • effect on resting and working HR??s • Fitness vs. Physical Activity- clarification

6. Benefits of Exercise: Weight Control • Exercise: changing the ratio of fat to muscle • weight loss issues in changing ratio in “heavy normals” vs. “obese”- lean weight concept • why we lose weight • caloric cost of exercise vs. sedentary behavior • changes in metabolic rate account for most of loss • Bennet & Gurin- exercise changes in set-point • loss of weight exceeds cost of regular exercise • Losing Weight vs. Controlling Weight- costs • 4 hours weekly walking • 1-3 hours weekly in moderate aerobic work

7. Cardiovascular Benefits of Physical Activity • Morris (1953)- London bus drivers and conductors • CHD lower in conductors • methodological problems- selection bias, random assignment • Kahn (1963)- importance of regular activity • natural cross-over comparisons between mail clerks and delivers- even if once active, after 5 years of sedentary job behavior-- CHD mortality protection is lost. • Still, self-selection biases remain • Paffenbarger: San Francisco Longshoreman • all initially active in vigorous cargo handling • address selection bias as all the same to start? • Still- flaws-- don’t include life outside job!

8. CV health and Physical Activity • The Paffenbarger Physical Activity Index • high (2000+) and low (less than 2000) kcals expended weekly during physical activities. • 2000 kcals is the arbitrary breakpoint see fig. 16.1!!- • an inverse relationship between PA and CHD up to 3500 kcals weekly • Framingham- men & women- • high active to sedentary- 3x decrease in CHD risk • Twin Studies- (control for genetics) • activity levels predicts longevity/health • Added Longevity and Quality of Life Issues (note)

9. Stroke and Cholesterol • Less clear results for stroke • 1/4 of all stroke deaths preventable in Eur Amer with a more active lifestyle • of greater efficacy for elderly and males • results less clear in younger women and Afr. American • Increase HDLs and decrease LDLs • dose response relationship between activity level and HDL • activity such as walking, gardening and other non-exercise leisure time activity also related • also found with children and young adults and animals

10. Other Health Benefits • Mixed evidence on Cancer • recreational exercise reduced breast cancer 12-60% • regular exercising women from early age have 50% less incidence of breast cancer • high intensity related to reduced colon cancer • Osteoporosis- exercise/phys. act protects • loss of bone mineral density- why important • of particular concern for elderly and post menopausal women • past (Wow!) and present exercise is helpful to retain bone density

11. Other Health Benefits (continued) • Diabetes • exercise related to Type II onset, treatment and mortality • Sleep • fall asleep faster, sleep longer • Psychological Effects- appears to be beneficial • Depression • Anxiety • Stress • Self-Esteem • Control problems in this research- • lack of placebo control group-- tough to find good placebo...

12. Physical Activity, Depression, Anxiety, Stress • Phys. Activity & Mental Health- Morgan (1998) • Aerobic activity vs. therapy, wait-list, relaxation • effective for moderate/mild depression • Phys Activity and Depression • More effective than no treatment & As effective as psychotherapy • Aerobic and Non-Aerobic equally effective in treatment • No dose response relationship • good for low-grade, but not major depression • (Blumenthal may be challenging this research) • no evidence relating PA to depression relapse • Mechanisms of action are unclear

13. Anxiety & Stress • State-Trait Anxiety • “moderate” vs. “vigorous” activity and mood • Stress= “Stress Response” • cv response, physical symptom response • Anxiety & Stress: how does it work? • Endorphins, “hot-tub hypothesis”, NE release • correction in book-- it can prepare body to handle stress effects more easily -- “cross-stressor hypothesis” • Self-Esteem • Body image is a perception-- cognitive dissonance effect with exercise

14. Hazards • Staleness- overtrainining-->neg. mood, fatigue, depression • Exercise Addictions- • neglect of responsibilities, self-absorption, continuation in spite of medical orders to stop- similar behavior to other addictions

15. Hazards continued • female endurance athletes and eating disorders • UT women x-country runners and PowerBars • Musculoskeletal injuries • Temperature and Physical Activity • Sudden death during physical activity • overstated risk in the media- must compare risk of SD in regular exercisers to non-exercisers • snow shoveling, deer hunting studies

16. Maintenance • Highest among • men, • past history of physical activity • higher education/income (SES) • younger • Lowest • smokers • blue-collar workers • low exercise self-efficacy • Increasing-- • minimize execuse making, add social support • Relapse Prevention models- abstinence violation effects- • warn participants of this!!