C-15A Free Communication/Slide Exercise and Weight Loss
The minimum amount of exercise recommended to improve health is approximately 150 min/wk (SGR 1996).
To examine whether the minimum public health recommended exercise dose is sufficient for improving long-term weight loss in overweight adults.
One hundred eight four sedentary women (BMI=32.6 ±4.2 kg/m2, age = 37.3 ±5.6 years) completed 12 months of a behavioral weight loss program. The dietary intervention included strategies to reduce energy intake and fat intake. Exercise was prescribed for 5 days/wk. Subjects where prescribed 30 to 60 minutes of exercise per day, with intensity ranging from moderate to vigorous. Subjects were grouped based on the amount of exercise completed at 6 month intervals (months 1–6 and months 7–12). Groups were the following: EX > 200 (> 200 min/wk), EX150 (150 to 200 min/wk), EX < 150 (< 150 min/wk).
There was a significant difference between groups in min/wk of exercise for months 1–6 (EX > 200=260 min/wk, EX150=176 min/wk, EX < 150=125 min/wk) and months 7–12 (EX > 200=269 min/wk, EX150=171 min/wk, EX < 150=101 min/wk) (p < 0.05), with no difference in exercise intensity between these exercise categories. Percent weight loss at 12 months was significantly greater in individuals performing more exercise (EX > 200=15%, EX150=10%, EX < 150=7%) (p < 0.05). Higher levels of exercise resulted in a greater increase in minutes to achieve 85% HRmax on a GXT following 12 months (EX > 200 = +5.7 min, EX150 = +3.5 min, EX < 150 = +2.8 min)(p < 0.05).
When combined with a dietary intervention, exercise greater than the minimum public health recommended dose significantly improves long-term weight loss and fitness compared to lower doses of exercise. Therefore, strategies to increase exercise to this higher level may be warranted. Supported by the National Institutes of Health (HL64991)