CREATINE SUPPLEMENTATION DURING TRAINING/COMPETITION DOES NOT INCREASE PERCEPTIONS OF FATIGUE OR ADVERSELY AFFECT HEALTH STATUS

Recent surveys have suggested that athletes who take creatine may experience side effects such as fatigue, cramping, and musculoskeletal injury. However, the incidence of these potential side effects among creatine users was not compared to a control group of athletes. This study examined perceptions of fatigue and health status among athletes who did and did not take creatine during training/competition. One hundred Division IA college football players participated in this study. Subjects completed a 15 item self-reported Fatigue Status Inventory and a 17 item Health Status/Side Effect Inventory once a week for 19 weeks during pre-season and in-season training/competition. Forty-eight (48%) of the subjects ingested creatine during training (15.75 g/d for 5 – 7 d and 5 g/d thereafter administered in 5 – 10 g doses). Creatine was administered by research assistants and ingested with carbohydrate or carbohydrate/protein supplements that were offered to all athletes after training sessions. Responses to the fatigue and health inventories for the creatine and non-creatine using athletes were compared using chi-square and Fisher's exact tests. Analysis of the fatigue inventory revealed that creatine users reported significantly less (p < 0.05) heart & lung fatigue (week 5), a more positive attitude towards practice (weeks 6–7), and that they felt physically stronger (week 13) than non-creatine users. Analysis of the health inventory revealed that creatine users reported more restful sleep (week 6) and less nasal congestion (week 5), coughing (weeks 6, 10, 16), ear tenderness/soreness (weeks 5 & 14), muscle cramping (week 10), and stomach upset (week 14) in comparison to athletes who did not take creatine. These findings indicate that athletes who take creatine during training may experience less fatigue and fewer symptoms of illness and side effects at various times during training in comparison to athletes who do not take creatine. These findings support recent reports that creatine supplementation during training does not adversely affect health status or cause a greater incidence of side effects. Supported by the ESNL, MetaResponse Sciences, EAS, MRM, & Traco Labs