Exercise and Weight Control Dr. David L. Gee FCSN 446/PE 446 Nutrition, Weight Control, and Exercise

Benefits of Exercise for Overweight Individuals n Weight Loss Related Benefits n Health Benefits Independent of Weight Loss n Psychological Benefits

Why do Americans not exercise?

Successful Approaches to Adopting and Maintaining a Physically Active Lifestyle n NIH Consensus Development Conference Statement, Dec n Perceives a net benefit –Chooses an enjoyable activity –Feels competent doing activity –Feels safe doing activity

Successful Approaches to Adopting and Maintaining a Physically Active Lifestyle n Easy access to activity n Activity fits into daily schedule n Financial and social costs acceptable n Minimum negative consequences –loss of time –negative peer pressure –problems with self esteem

Successful Approaches to Adopting and Maintaining a Physically Active Lifestyle n Able to successfully address issues of competing time demands n Balance labor saving devices and sedentary activities with activities that involve higher levels of physical exertion

Exercise for the Weight Loss: Intensity vs. Duration n Recommendations for overweight subjects who are sedentary n Begin with lower intensity exercises n Work on increasing duration first n Focus on regular program (5-7 days/week) n Gradually increase intensity once available time is limiting n Add weight training if time permits n Just do it!

OK, exercise is important. But, how important is “everyday/lifestyle” activity?

Lifestyle vs Structured Activity n JAMA (Jan. 1999) n Sedentary men (116) & women (119) n 6 months intensive intervention –lifestyle physical activity program –structured exercise program n 18 months maintenance intervention

Lifestyle vs Structured Activity

Conclusions: Lifestyle Programs have similar beneficial changes as Structured Exercise Programs

Training Effects of Short and Long Bouts of Brisk Walking in Sedentary Women. MSSE 30: (1998) n 47 HRmax, 5X/wk, 10 weeks –Long walks: 30 min walking –Short walks: 3x10 min walking n Aerobic capacity increased equally in both walking groups n Decreases in BW was greater in short walk (1.7kg) than long walkers (0.9kg) n Waist circumference decreased greater in short walk (3cm) than long walkers (1.8cm) n Conclusion: accumulations of shorter walks at least as beneficial as single long walk.

Effects of intermittent exercise and use of home exercise equipment on adherence, weight loss, and fitness. JAMA 282: n 148 obese women, 18 month weight loss program –home treadmill min/wk walks –home treadmill min/wk walks –no equipment min/wk walks n Weight loss equal in first 6 months –(6-7kg) n Weight regain similar in last 12 months –1.5-4kg, slightly higher in group w/o treadmill

Effects of intermittent exercise and use of home exercise equipment on adherence, weight loss, and fitness. JAMA 282: n Dose-response relationship between weight loss/maintenance and weekly exercise time. n 150 min/wk: –7kg 6 mo, 3.5 kg regain at 18 mo. n min/wk –10.5 kg 6 mo, 2 kg regain at 18 mo. n >200 min/wk –12.5 kg 6 mo, no regain at 18 mo. –200min/wk = 2-3 walks/day for 10-15min each

n Active/highly active –> 10,000 steps/day –20% men –13% women n Sedentary lifestyle –< 5,000 steps/day –32% men –33% women

n Factors affecting steps/day n Age –Younger>older n Income –Low<high –Ethnicity NS n Marital status –Single/divorce>married n BMI –Obese<overweight<normal

Conclusion: n “Increasing steps per day appears to be a good target to use in interventions to increase physical activity.” n “Even in Colorado, one of the leanest states, very low levels of physical activity are seen in much of the population.”

Exercise Recommendations n Old ACSM Recommendations (1990) –3-5 days/week –60-90% of max. HR –20-60 min/session n ACSM 2002 –30 minutes of moderate exercise most days of the week n IOM – DRI Energy –60 minutes of moderate exercise 7 days a week

Dr. Gee’s Recommendations for Exercise and Weight Loss n Priority 1 –Emphasize active lifestyle every day –brainstorm ideas –Pedometers & 10,000 step programs n Priority 2 –Include structured exercise most every day –focus first on endurance, second on intensity n Priority 3 –Incorporate weight training 2-3x/week

Considerations for the Overweight Exerciser n Many of those overweight: – are currently inactive – were never active – feel awkward exercising – have poor self image

Considerations for the Overweight Exerciser n Very gradual introduction and progress n Appropriate types of exercise n group support n instructor support n low impact n heat intolerant n measure HR frequently

Considerations for the Overweight Exerciser n Make it a high priority (incentives) n Use as a substitute for problem behavior, not as a punishment n measure girth in addition to weight