Background: Physical activity recommendations promote the accumulation of aerobic activity in bouts of >or=10 min. It is important to determine whether shorter bouts of activity can influence health.
Objective: We compared the effects of accumulating ten 3-min bouts of brisk walking with those of one 30-min bout of brisk walking on postprandial plasma triacylglycerol concentrations and resting blood pressure.
Design: Fifteen healthy young men completed three 2-d trials >or=1 wk apart in a randomized, repeated-measures design. On day 1, subjects rested (no exercise) or walked briskly in either ten 3-min bouts (30 min rest between each) or one 30-min bout (gross energy expenditure: 1.10 MJ/30 min). On day 2, subjects rested and consumed high-fat test meals for breakfast and lunch.
Results: On day 2 area under the plasma triacylglycerol concentration over time curve was 16% lower on the accumulated and continuous brisk walking trials than on the control trial (x +/- SEM: 9.98 +/- 0.67 compared with 9.99 +/- 0.76 compared with 11.90 +/- 1.02 mmol x 7h/L, respectively; P = 0.005, one-factor ANOVA). Resting systolic blood pressure was 6-7% lower throughout day 2 on the accumulated and continuous trials than on the control trial (109 +/- 1 compared with 110 +/- 1 compared with 117 +/- 2 mm Hg, respectively; P < 0.0005).
Conclusion: Accumulating 30 min of brisk walking in short (3-min) bouts is equally effective in reducing postprandial lipemia and systolic blood pressure as is one continuous 30-min bout.