Postexercise Cold-Water Immersion Does Not Attenuate Muscle Glycogen Resynthesis

Purpose: The aim of this study was to test the hypothesis that postexercise cold-water immersion (CWI, via its associated reductions in skeletal muscle blood flow) attenuates muscle glycogen resynthesis during short-term recovery from exhaustive exercise. Methods: In a repeated-measures design, nine recreationally active men performed an exhaustive glycogen depleting cycling protocol (consisting of intermittent exercise the night before and steady-state exercise on the subsequent morning of the main trial) followed by 10 min of lower-limb CWI (8 degrees C) or remained seated in normal ambient conditions (CONT). Subjects were fed carbohydrate (CHO) at an ingestion rate of 0.6 g.kg(-1) body mass at 30 min postexercise and at 1, 2, and 3 h postexercise. Results: Reductions in thigh skin temperature and muscle temperature during postexercise recovery were greater in CWI compared with CONT (P < 0.01). In addition, norepinephrine and blood glucose concentrations were increased and decreased, respectively, during recovery in CWI compared with CONT (P < 0.01). Postexercise muscle glycogen (CONT and CWI postexercise = 76 +/- 43 and 77 +/- 26 mmol.kg(-1) dry weight [dw], respectively; mean +/- SD) progressively increased (P G 0.01) during recovery, although rates of resynthesis did not differ (P = 0.719) between conditions (CONT and CWI 4 h postexercise = 160 +/- 34 and 157 +/- 59 mmol.kg(-1) dw, respectively). Total glycogen synthesis during recovery was comparable (CONT and CWI = 83 +/- 43 and 79 +/- 58 mmol.kg(-1) dw, respectively). Conclusions: Postexercise CWI does not attenuate muscle glycogen resynthesis rates during short-term recovery even when CHO availability is considered suboptimal. Athletes who regularly incorporate CWI as a recovery strategy to alleviate symptoms of exercise-induced muscle damage should therefore not be concerned with potential negative effects of the associated reductions in muscle blood flow on the restoration of muscle glycogen stores.