Mh. Murphy et al., Different patterns of brisk walking are equally effective in decreasing postprandial lipaemia, INT J OBES, 24(10), 2000, pp. 1303-1309
OBJECTIVE: To compare the effects of different patterns of brisk walking on
day-long plasma triacylglycerol concentrations in sedentary adults.
DESIGN: A three-trial, repeated measures design in which subjects were stud
ied in the fasted state and throughout a day during which they consumed thr
ee standardized, mixed meals. On different occasions, subjects undertook no
exercise (control), walked briskly for 10 min before each meal (short walk
s) or walked briskly for 30 min before breakfast (long walk).
SUBJECTS: Seven postmenopausal sedentary women and three sedentary men aged
between 34 and 66 y, with body mass index between 24 and 35 kg/m(2).
MEASUREMENTS: Plasma concentrations of triacylglycerol, non-esterified fatt
y acids, glucose and insulin, metabolic rate and whole-body substrate oxida
tion in the fasted state and at hourly intervals for 3 h after each meal.
RESULTS: Postprandial plasma triacylglycerol concentrations were lower (P =
0.009) during the walking trials than during the control trial (average va
lues: control 2.08 +/- 0.28 mmol/l;short walks 1.83 +/- 0.22 mmol/l; long w
alk 1.84 +/- 0.22 mmol/l (mean +/- s.e.) but did not differ between the two
patterns of walking. The difference between control and walking trials inc
reased as successive meals were consumed (interaction of trial x meal P = 0
.03), Plasma triacylglycerol concentration increased during the 3 h after b
reakfast, changed little after lunch and decreased after the evening meal (
interaction of meal x time P = 0.001). When both walking trials were treate
d as one condition, walking increased postprandial fat oxidation (average v
alues: control, 0.066 +/- 0.009 g/min;walking 0.074 +/- 0.008 g/min; P < 0.
01).
CONCLUSIONS: Thirty minutes of brisk walking, undertaken in one session or
accumulated throughout a day, reduces postprandial plasma triacylglycerol c
oncentrations and increases fat oxidation.