Glycemic responses to low-intensity, short-duration aerobic exercise sessions in hospitalized women with gestational diabetes: a pilot study

Abstract

Objective This study aimed to investigate the effects of low-intensity aerobic exercise performed once (30 min; A30) or twice a day (15+15 min; A15+15) on pre- and postprandial capillary blood glucose (CBG) levels on the day of the exercise session (D1) and the following day (D2) in hospitalized women with gestational diabetes mellitus (GDM). Subjects and methods In this crossover study, nine participants adhered to a standard hospital diet and completed 2-day trials under three conditions: A30 (30 min in the afternoon), A15+15 (15 min in the morning and afternoon), and resting (REST). Participants completed the REST condition first. Preprandial (immediately before meals) and postprandial (60 min after main meals) CBG levels were measured. Exercise sessions comprised cycling at 50%–65% of maximal heart rate using a friction-based pedal. Data were analyzed using generalized estimating equations with Bonferroni post hoc analysis. Results Pooled data from D1 and D2 (six measurements each day) showed lower CBG levels in the A15+15 condition (5.7 ± 0.3 mmol/L) compared to REST (6.3 ± 0.6 mmol/L) (~-9.5%) (p = 0.001); however, this finding carried limited clinical significance. There were no differences among the three experimental conditions when considering the same pre- and postprandial time points. Conclusion Short-duration, low-intensity aerobic exercise sessions (A15+15) attenuated overall daily (pre- and postprandial) glycemia in hospitalized women with GDM. This attenuation was only observed in the pooled data, as glucose levels did not differ at specific postprandial time points.