Purpose: To compare the effects of different patterns of regular brisk walking on fitness, risk factors for cardiovascular disease, and psychological well-being in previously sedentary adults.
Methods: Twenty-one subjects (14 women), aged 44.5 +/- 6.1 yr (mean +/- SD) were randomly assigned to two different, 6-wk programs of brisk walking in a cross-over design, with an interval of 2 wk. One program comprised one 30-min walk per day, 5 d.wk(-1) (long bout) and the other three 10-min walks per day, also 5 d.wk(-1) (short bouts). All walking was at 70-80% of predicted maximal heart rate. Maximal oxygen uptake ((.)VO(2max)), body composition, resting arterial blood pressure, fasting plasma lipoprotein variables, and psychological parameters were assessed before and after each program.
Results: Overall, subjects completed 88.2 +/- 1.1% and 91.3 +/- 4.1% of prescribed total walking time in the short- and long-bout programs, respectively. Both programs increased plasma concentrations of high-density lipoprotein cholesterol, and decreased concentrations of triacylglycerol and total cholesterol (all < 0.05). There were no changes in body mass, but the sum of four skinfolds, waist circumference, and hip circumference were decreased after both walking programs (all P<0.05). Predicted (.)VO(2max) increased with both programs ( P<0.05), but this increase was greater with the program based on short bouts (P<0.05). Both walking patterns resulted in similar decreases in tension/anxiety (P<0.05).
Conclusion: These findings suggest that three short bouts (10 min) of brisk walking accumulated throughout the day are at least as effective as one continuous bout of equal total duration in reducing cardiovascular risk and improving aspects of mood in previously sedentary individuals.