Comparison between two post exercise cooling methods

Abstract

SummaryForty‐two fit 3‐day‐event horses were tested under hot, humid ambient conditions to determine if application of cold water (mean 9°C) over the entire body surface after exercise would cool horses more quickly than regional application of tepid water (mean 31°C); and to determine if topical application of cold water caused myopathy. Horses were exercised under saddle for an average of 81 min. Heart rate data and post exercise plasma lactate concentrations characterised the work effort as low intensity work with short bouts of moderate intensity effort.Sixteen horses were studied in a crossover design on 2 consecutive days. Immediately after exercise, horses were randomly assigned to the hypercooling protocol (cold water on entire body surface) or the conventional protocol (tepid water on neck, shoulders, torso, underside and legs). Hypercooled horses (Group 1) had significantly lower rectal temperatures at 15, 20, 25 and 30 min after exercise compared to conventionally cooled horses (Group 2). In a supplemental study, an additional 19 horses (Group 3) were hypercooled after exercise. Mean rectal temperatures were significantly decreased from the immediate post exercise rectal temperature at 10, 15, 20 and 25 min after exercise. Based on physical examination and serum AST and CK concentrations, myopathy did not occur in any of the horses. These results suggest that application of cold water to the entire body surface relieves mild to moderate exertional hyperthermia quickly under hot, humid conditions; and that myopathy is not a common complication of this cooling approach.