To the Editor: Dr Jakicic and colleagues1 concluded that vigorous exercise intensity was not superior to moderate exercise intensity for weight loss in a 12-month physical activity program with additional restriction in dietary fat and caloric intake.
To help explain this unexpected finding, we suggest that the intensity-dependent effect of physical activity on body composition should be taken into account. A higher intensity level of physical activity leads to a more pronounced shift in the relationship of fat mass with fat-free mass (specifically, skeletal muscle mass) with only minimal changes in body weight.2 - 3 Thus, the apparent lack of an effect of intensity may be due to higher postintervention fat-free mass in the individual who exercised vigorously. This potential benefit of higher exercise intensity could have been assessed with measurement of body composition.
Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature
Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal
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