Effects of exercise before and/or after a mixed lunch on postprandial metabolic responses in healthy male individuals

PURPOSE: Exercise plays an important role in preventing and treating postprandial dysmetabolism. We investigated the postprandial metabolic responses to a standard lunch when a session of aerobic exercise is performed in the early postprandial phase or divided between the pre- and postprandial period.METHODS: Nine healthy volunteers consumed a standardised mixed lunch and rested for the following 3h (Con) or performed 40min of cycling at 65% VO2max after lunch (CPPEx), or two 20-min sessions, one before (SplitEx1) and the other after lunch (SplitEx2), at the same intensity.RESULTS: At 1-h post-lunch, a significant reduction (P<0.001) in glycaemia was observed for CPPEx (-25±10%) and SplitEx (-34±7%) compared to Con. Yet, a post-exercise rebound lessened the exercise effect on the glycaemic area under the curve (AUC) at 2 and 3h. At 1h, a significant reduction (P<0.009) in plasma insulin (SplitEx -53±31%; CCPEx -48±20%) and C-peptide (SplitEx -57±20%; CCPEx -47±24%) was observed compared to Con. Glucose-dependent insulinotropic polypeptide (GIP) increased after the meal, without differences between conditions. Compared with SplitEx1, cortisol response was attenuated during SplitEx2 and CPPEx. At 3 hours, triglyceride AUC was significantly higher (P=0.039) in SplitEx compared to Con (+19±8%).CONCLUSION: Forty minutes of postprandial exercise or 20min of pre- and postprandial exercise are both effective at attenuating the glycaemic and insulinaemic response to a mixed lunch, while a higher lipaemia was found in the pre- and postprandrial exercise condition.