1. 1 Exercise and obesity: prevention and treatment How effective is exercise?

2. 2 BMI and mortality Sharper, 1997

3. 3 Obesity prevalence in world BMI > 30 Finucane 2011

4. 4 Overweight prevalence in world BMI > 25 Finucane 2011

5. 5 Energy balance

6. 6 National Runners’ Study: 18-49 yo: 4769 >49 yo: 2150 Male runners Cross-sectional Williams 1997

7. 7 Walking and weight reduction Richardson, 2008

8. 8 Walking and weight reduction dose-response relation Richardson, 2008

9. 9 Caloric reduction + walking / jogging, Obese female

10. 10

11. 11 Wadden, 2011

12. 12 Wadden, 2011

13. 13 PA additive to caloric restriction PA alone insufficient Chaput, 2011

14. 14 Diet intervention Mozaffarian, 2011

15. 15 Diet intervention Mozaffarian, 2011

16. 16 No diet-PA interaction Mozaffarian, 2011

17. 17 Coordinated Approach To Child Health (CATCH): school vs school+community OW+OB ↓1.3% OW+OB ↓8.2% Hoelscher, 2010

18. 18 Coordinated Approach To Child Health (CATCH): school vs school+community Hoelscher, 2010

19. 19 NEW Kids Program: multidisciplinary cognitive behavioral modification in OW/OB child After > 9 months Skelton, 2008

20. 20 Mind, Exercise, Nutrition, Do it (MEND) :multicomponent community-based child obesity intervention Sacher, 2010

21. 21 School-based intervention on energy balance behaviors: mostly ineffective Yildirim, 2011

22. 22 Change in BW after 12 wk in elderly Witham 2010

23. 23 Change in cholesterol after 12 wk in elderly Witham 2010

24. 24 Shift in energy balance? 10% reduction in body weight is associated with 20-30% decrease in activity energy expenditure independent of time spent in physical activity Change in balance?

25. 25

26. 26 Energy expenditure oppose the altered body weight Liquid diet + prescribed exercise ↓BW  ↓TEE, ↓REE, ↓nonresting (PA) EE Resenbaum 2003

27. 27 Decrease BW  increase skeletal muscle efficiency Resenbaum 2003

28. 28 Decrease BW  increase skeletal muscle efficiency Resenbaum 2003

29. 29 ↓ energy expenditure in walking after very- low energy diet + walking in obese women Foster 1995

30. 30 ↓ energy expenditure in walking after very- low energy diet + walking in obese women Foster 1995

31. 31 EE during inactivity and MVPA compensation, but not complete Garland Jr, 2011

32. 32 Monkey Sullivan, 2010

33. 33 Subjects who have lost 10% BW at Year 1 Wadden, 2011

34. 34 Subjects who have lost 10% BW at Year 1 Wadden, 2011

35. 35 ‘Set point’ theory Body has a weight ‘set point’ Maintenance of reduced or elevated body weight associated with compensatory changes in energy expenditure (BMR) Weight cycling: yo-yo effect After weight loss, it is regained in relatively short time

36. 36 Set point and settling points there is biological (active) control of BW, and also weight stability (and thus a set point at a healthy steady state) in response to eating healthy chow diets By contrast, this regulation is lost by Western diets failure of biological control is due mainly to external factors In this situation, the set point is replaced by various settling points that are influenced by energy and macronutrient intake in order for the body to reach a zero balance of energy and macronutrients and thus a new and possibly unhealthy steady state Muller, 2010

37. 37 International Association of Study of Obesity consensus The current physical activity guideline for adults of 30 minutes of moderate intensity activity daily, preferably all days of the week, for preventing weight gain or regain this guideline is likely to be insufficient for many individuals in the current environment. Prevention of weight regain in formerly obese individuals requires 60–90 minutes of moderate intensity activity or lesser amounts of vigorous intensity activity. moderate intensity activity of approximately 45-60 minutes per day is required to prevent the transition to overweight or obesity. For children, even more activity time is recommended. incorporating more incidental and leisure-time activity into the daily routine Saris 2003, Jakicic 2005

38. 38 Finkelstein et al, 2004

39. CATCH Program Coordinated Approach To Child Health BasicPlus, CATACH BP+community CATCH program incorporated elements of social ecological models and Social Cognitive Theory Broader and more community-focused approach extend school programs to the surrounding community 39 Hoelsche r et al, 2010

40. Programs to reduce child obesity 40 Hoelsche r et al, 2010

41. Results of CATCH programs 41 Hoelsche r et al, 2010

42. Conclusion Implementation of a community-enhanced school program can be effective in reducing the prevalence of child overweight in low- income student populations 42 Hoelsche r et al, 2010

43. Meta-analysis of weight change in 12 months in the elderly 43 Witham and Avenell, 2010

44. Meta-analysis of change in total cholesterol in 12 months in elderly 44 Witham and Avenell, 2010

45. Conclusions Blood lipids, blood pressure, mortality, morbidity, hospitality, quality of life, glycemic control only appeared in few studies and inconclusive although modest weight reductions were observed, there is a lack of high-quality evidence to support the efficacy of weight loss programs in older people 45 Witham and Avenell, 2010

46. Exercise intensity and duration on weight loss 46 Church, 2011

47. TEE in men 47 Low-mid human development index high human development index Dugas et al, 2010

48. TEE in women 48 Low-mid human development index high human development index Dugas et al, 2010

49. Conclusions TEE adjusted for weight and age or PAL did not differ significantly between developing and industrialized countries the role of energy expenditure in the cause of obesity at the population level? 49 Dugas et al, 2010

50. Factors of TEE 50 Dugas et al, 2010

51. Factors of physical activity level 51 Dugas et al, 2010

52. Individual differences Tremendous variation in responses some lost significant amounts of weight some actually gaining weight Partly due to how completely individuals compensate for exercise with elevated food intake, which corresponds to their hunger after exercise. 52 Hall et al, 2012

53. PA on resting energy expenditure positive effect of vigorous or moderate PA on REE in 2 separated phases. a large effect that lasts ~2 h a smaller but more prolonged effect that could take up to 48 h to return to baseline excess post-exercise oxygen consumption 6– 15% of the energy expended during an exercise session, which adds little to TEE. impact of exercise training on REE is negligible 53 Hall et al, 2012

54. Energy balance and weight change Traditional thinking: 7500 kcal expenditure equals to 1 kg fat loss Too optimistic, too simplified every permanent 10-kcal change in energy intake/d will lead to an eventual weight change of 1 pound when the body weight reaches a new steady state It will take ~1 year to achieve 50%, and ~3 year to achieve 95% of this weight loss 54 Hall et al, 2012

55. Body weight simulator http://bwsimulator.niddk.nih.gov http://www.pbrc.edu/the- research/tools/weight-loss-predictor http://www.pbrc.edu/the- research/tools/weight-loss-predictor 55