Postmeal walking reduces nighttime central SBP and increases nocturnal dipping of SBP in healthy, physically inactive young women.

INTRODUCTION

Postmeal walking (PMW) blunts postprandial blood glucose, but the impact on postexercise hypotension and ambulatory blood pressure (BP) has not been examined in young women. Further, it remains unknown how PMW influences ambulatory central BP among young women.

METHODS

Fourteen physically inactive, nonhypertensive women (20 ± 1 years; body fat: 28.1 ± 12%) completed the study during the early follicular or placebo phase of their contraceptive cycle. Participants completed a control day (CON; no exercise/excess physical activity) and PMW day (three bouts for 15 min of brisk walking). Ambulatory brachial and central BP (24 h, daytime, nocturnal, postexercise BP, nocturnal dipping) and accelerometry data were collected.

RESULTS

PMW reduced 24 h central augmentation pressure (PMW = 9 ± 4 mmHg; CON=10 ± 5 mmHg, P  = 0.049) and central pulse pressure (PMW = 31 ± 3 mmHg; CON=33 ± 4 mmHg, P  = 0.02). PMW also reduced nighttime central augmentation pressure (PMW = 10 ± 4 mmHg; CON = 13 ± 4 mmHg, P  < 0.001) and central pulse pressure (PMW = 35 ± 5 mmHg; CON = 32 ± 3 mmHg, P  = 0.001). PMW induced postexercise hypotension (effect of time: P  < 0.05), but there was no effect of condition ( P  > 0.05 vs. CON), as the CON postprandial state also induced a hypotensive effect. PMW increased heart rate (main effect of condition, P  = 0.01). PMW also increased brachial SBP nocturnal dipping (PMW = 17.5 ± 4.2; CON = 14.4 ± 5.2%, P  < 0.05) and central SBP nocturnal dipping (PMW = 6.8 ± 4.5; CON = 12.2 ± 5.3%, P  < 0.01). Brachial and central DBP nocturnal dipping was not different between conditions (PMW = 23.7 ± 5.9%, CON = 22.3 ± 7%, P  = 0.50; PMW = 25 ± 6.4%, CON = 21.9 ± 5.6%, P  = 0.13, respectively).

CONCLUSION

PMW exerts the greatest influence on nighttime SBP and nocturnal dipping of SBP in young women. PMW also induces a similar hypotensive response that occurs following a meal.