Short-term Creatine Supplementation Suppresses the Cortisol Response to a High-Intensity Swim-Sprint Workout

Abstract

The primary aim of the present study was to evaluate the effects of creatine ingestion on the metabolic hormone cortisol in male swimmers. Seventeen male swimmers (24.5 ± 3.9 years) with at least 5 years of competitive swimming experience and engaged in swimming training at least 4 times per week participated in the study. Subjects supplemented with creatine (20 g/day) + maltodextrin (1g/kg/day) or maltodextrin (1g/kg/day) only for 6 days prior to a progressive swim-sprint workout. The swim-sprint workout consisted of 8 progressive 100 meter freestyle sets starting at 65% of maximal intensity leading up to a 100% maximum capacity set on the eighth and final set. Cortisol was assessed immediately before and immediately after (within 5 minutes) the swim-sprint workout. After 6 days of creatine monohydrate supplementation, there was a significant reduction in cortisol concentrations following the progressive swim-sprint workout in the creatine + maltodextrin group (15.5 ± 0.99 μg/dL) as compared to the maltodextrin only group (18.33 ± 2.61 μg/dL). Based on these findings, it appears that creatine loading (20 grams per day for 6 days) significantly reduces the cortisol response to 100-meter freestyle swimming sets performed in a progressive intensity manner.