Use the Back button in your browser to see the other results of your search or to select another record.

Detailed Search Results

Randomised, controlled walking trials in postmenopausal women: the minimum dose to improve aerobic fitness? [with consumer summary]
Asikainen TM, Miilunpalo S, Oja P, Rinne M, Pasanen M, Uusi-Rasi K, Vuori I
British Journal of Sports Medicine 2002 Jun;36(3):189-194
clinical trial
6/10 [Eligibility criteria: Yes; Random allocation: Yes; Concealed allocation: No; Baseline comparability: Yes; Blind subjects: No; Blind therapists: No; Blind assessors: No; Adequate follow-up: Yes; Intention-to-treat analysis: Yes; Between-group comparisons: Yes; Point estimates and variability: Yes. Note: Eligibility criteria item does not contribute to total score] *This score has been confirmed*

BACKGROUND: The American College of Sports Medicine recommends 20 to 60 minutes of aerobic exercise three to five days a week at an intensity of 50 to 85% of maximal aerobic power (VO2max) reserve, expending a total of 700 to 2,000 kcal (2.93 to 8.36 MJ) a week to improve aerobic power and body composition. OBJECTIVE: To ascertain the minimum effective dose of exercise. METHODS: Voluntary, healthy, non-obese, sedentary, postmenopausal women (n = 121), 48 to 63 years of age, were randomised to four low dose walking groups or a control group; 116 subjects completed the study. The exercise groups walked five days a week for 24 weeks with the following intensity (% of VO2max) and energy expenditure (kcal/week): group W1, 55%/1,500 kcal; group W2, 45%/1,500 kcal; group W3, 55%/1,000 kcal; group W4, 45%/1,000 kcal. VO2max was measured in a direct maximal treadmill test. Submaximal aerobic fitness was estimated as heart rates at submaximal work levels corresponding to 65% and 75% of the baseline VO2max. The body mass index (BMI) was calculated and percentage of body fat (F%) estimated from skinfolds. RESULTS: The net change (the differences between changes in each exercise group and the control group) in VO2max was 2.9 ml/min/kg (95% confidence interval (CI) 1.5 to 4.2) in group W1, 2.6 ml/min/kg (95% CI 1.3 to 4.0) in group W2, 2.4 ml/min/kg (95% CI 0.9 to 3.8) in group W3, and 2.2 ml/min/kg (95% CI 0.8 to 3.5) in group W4. The heart rates in standard submaximal work decreased 4 to 8 beats/min in all the groups. There was no change in BMI, but the F% decreased by about 1% unit in all the groups. CONCLUSIONS: Walking (for 24 weeks) at moderate intensity 45% to 55% of VO2max, with a total weekly energy expenditure of 1,000 to 1,500 kcal, improves VO2max and body composition of previously sedentary, non-obese, postmenopausal women. This dose of exercise apparently approaches the minimum effective dose.
Reproduced with permission from the BMJ Publishing Group.

Full text (sometimes free) may be available at these link(s):      help