IMPLICATIONS OF THE TRADITIONAL AND THE NEW ACSM PHYSICAL-ACTIVITY RECOMMENDATIONS ON WEIGHT-REDUCTION IN DIETARY TREATED OBESE SUBJECTS

OBJECTIVE: To assess the acceptance of the traditional American Colleg e of Sports Medicine (ACSM) exercise recommendation (20-60 min of vigo rous exercise at least three times per week) and of the new, broader C enters for Disease Control (CDC)/ACSM physical activity recommendation (30 min of moderate intensity activities on most days of the week) in an obese population and to elucidate the implications of meeting thes e recommendations on weight reduction during dietary treatment. DESIGN : Prospective dietary intervention study of 1000 kcal diet daily. SUBJ ECTS: 109 obese subjects (age: 45.6 +/- 13.1 y, body mass index (BMI): 38.1 +/- 6.0 kg/m(2), (Female/Male: 81/19%) MEASUREMENTS: The time sp ent in moderate (3-6 MET, metabolic equivalents) and vigorous (6-10 ME T) physical activities was assessed by use of the ford-7-Day-Physical- Activity-Recall-Questionnaire, with subsequent allocation of the subje cts to one of three physical activity groups: meeting the traditional recommendation (TR), the new recommendation (NR) or neither of both (S ED, sedentary subjects). Physical activity level, physical activity en ergy expenditure, total energy expenditure (based upon the questionnai re) and resting metabolic rate (by standard equation) were estimated a t baseline. Body weight was determined at baseline and after a mean of 16.3 weeks of dietary treatment. RESULTS: The new, broader recommenda tion was met by twice as many of the obese subjects (34%) as was the t raditional recommendation (17%). Weight reduction at follow up (- 8.2 +/- 6.5 kg, 16.3 +/- 4.3 weeks, mean +/- s.d.) was positively correlat ed with the physical activity level at baseline (r = 0.49, P < 0.001). Meeting either the traditional or the new recommendation was associat ed with greater weight loss [-11.9 +/- 8.5 kg (TR) and -10.1 +/- 6.4 k g (NR), respectively, not statistically significant (NS)] as compared to being sedentary [ - 6.5 +/- 5.2 kg (SED), P < 0.05 vs both NR and T R]. CONCLUSIONS: Not only participation in vigorous exercise, but also regular engagement in moderate intensity physical activities, as rece ntly recommended by the CDC/ACSM, predicts greater weight reduction du ring dietary treatment, compared to being sedentary. The new, broader physical activity recommendation appears to be more readily accepted b y obese subjects than the former ACSM recommendation on exercise train ing.