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CREATINE SUPPLEMENTATION DURING PRE-SEASON FOOTBALL TRAINING DOES NOT AFFECT FLUID OR ELECTROLYTE STATUS

1999; Lippincott Williams & Wilkins; Volume: 31; Issue: Supplement Linguagem: Inglês

10.1097/00005768-199905001-01481

1530-0315

Christopher J. Rasmussen, Richard B. Kreider, Jason I. Ransom, J. Hunt, C. Melton, T. W. F. Stroud, E. Cantler, P. Milnor,

Exercise and Physiological Responses

1485 Anecdotal reports suggest that creatine supplementation during intense training in the heat may alter electrolyte status and/or promote dehydration. This study examined the effects creatine supplementation on fluid and electrolyte status during two phases of pre-season college football training. 53 Division IA football players (19.9±0.2 yrs; 185±1 cm, 103±2.6 kg) participated in the first phase of a long-term open label study to evaluate the medical safety of creatine supplementation. 34 subjects ingested a commercially available supplement containing 15.75 g/d of creatine for 5-d followed by ingesting 5.25 g/d of creatine for 20-d. Remaining subjects were provided a carbohydrate/protein supplement containing no creatine. Supplements were administered following daily training sessions. Training during phase 1 consisted of 4-5 d/wk (70±7 min per workout) of resistance-training indoors (28±1°C, 79±2% RH) and sprint/agility conditioning outdoors (32±0.9°C, 84±3% RH). Training during phase II involved subjects practicing 2 to 3 times per day for 1.5 to 3.5 h (207±17 min/d, 6 d/wk) during 17-d of preseason football camp in which environmental conditions ranged from 29 to 37°C, 58 to 91% R.H. (33.7±0.6°C, 79±2.4% R.H.). During phase II, subjects in the creatine group ingested a carbohydrate/protein supplement containing 8.3 g/d of creatine. Prior to and following each phase of training, body weight, total body water via bioelectrical impedance, fasting blood, and 24-hr urine samples were obtained. During camp, pre-and post practice body weights were recorded on all players (n=100). Data were analyzed by repeated measures ANOVA. Results revealed no significant interactions (p>0.05) between groups in total body weight, total body water; urine output, specific gravity; hematocrit, hemoglobin, blood volume, plasma volume or serum sodium, chloride, potassium, phosphorus, calcium, total protein, and albumin. No significant differences were observed between creatine users and non-users in weight loss (kg or %) during practices. Results indicate that creatine supplementation during 25-d of preseason conditioning and 17-d of football camp in an hot/humid environment does not affect markers of fluid or electrolyte status. Supported by Experimental & Applied Sciences, Golden CO & University of Memphis.