Sauna-Induced Rapid Weight Loss Decreases Explosive Power in Women but not in Men

Abstract

This study aimed at investigating to what extent sauna-induced dehydration is effective to rapidly decrease body weight and whether this practice alters strength and/or explosive power (jump capacity) in healthy athletes. We also investigated whether the observed changes could be rapidly reversed through rehydration. Six male (aged 21.6 ± 1.8 y) and six female (aged 24.5 ± 3.7 y) athletes who were not familiar with weight cutting procedures were tested on three occasions: 1) before sauna, 2) after three consecutive sauna sessions (3 × 20 min at 70 °C, with 5 min rest interval), and 3) after one hour rehydration period (2.5 ml/kg body weight every 15 min). For rehydration, a carbohydrate beverage (6.3 % glucose, 9.5 mmol/l Na⁺, 10 °C) was used. Evaluation consisted of body composition, strength (row-strength, handgrip-strength) and jump capacity (squat jump, counter-movement jump and elastic capacity). Sauna-induced dehydration, significantly decreased body weight in men (- 1.8 ± 0.5 %) and women (-1.4 ± 0.6 %). This reduction could not be rapidly reversed through rehydration. This weight cutting scheme did not affect strength or jump capacity in men. In women, a statistically significant decrease in squat jump was manifested after rehydration compared to pre-sauna values 23.7 ± 2.2 vs. 25.2 ± 1.4 cm, p < 0.05). The squat jump decrease in women was linearly and directly related to the percent reduction of body weight.

Key words

Weight loss - sauna - dehydration - rehydration - explosive power - weight class events

• 1 Barr S I. Effects of dehydration on exercise performance.  Can J Appl Physiol. 1999;  24 164-172
• 2 Fogelholm M. Effects of bodyweight reduction on sports performance.  Sports Med. 1994;  18 249-267
• 3 Ftaiti F, Grelot L, Coudreuse J M, Nicol C. Combined effects of heat stress, dehydration and exercise on neuromuscular function in humans.  Eur J Appl Physiol. 2001;  84 87-94
• 4 Gisolfi C V, Summers R W, Lambert G P, Xia T. Effect of beverage osmolality on intestinal fluid absorption during exercise.  J Appl Physiol. 1998;  85 1941-1948
• 5 González-Alonso J, Mora-Rodríguez R, Coyle E F. Stroke volume during exercise: interaction of environment and hydration.  Am J Physiol. 2000;  278 321-330
• 6 González-Gross M, Gutiérrez A, Mesa J L, Ruiz J, Castillo M J. La nutrición en la práctica deportiva.  Arch Latinoam Nutr. 2001;  51 321-331
• 7 Greiwe J S, Staffey K S, Melrose D R, Narve M D, Knowlton R G. Effects of dehydration on isometric muscular strength and endurance.  Med Sci Sports Exerc. 1998;  30 284-288
• 8 Gutiérrez A, González-Gross M, Delgado M, Castillo M J. Three days fast in sportsmen decrease physical work capacity but not strength or perception-reaction time.  Int J Sport Nutr. 2001;  11 415-424
• 9 Hall C J, Lane A M. Effects of rapid weight loss on mood and performance among amateur boxers.  Br J Sports Med. 2001;  35 390-395
• 10 Hickner R C, Horswill C A, Welker J M, Scott J, Roemmich J N, Costill D L. Test development for the study of physical performance in wrestlers following weight loss.  Int J Sports Med. 1991;  12 557-562
• 11 Hoffman J R, Stavsky H, Falk B. The effect of water restriction on anaerobic power and vertical jumping height in basketball players.  Int J Sports Med. 1995;  16 214-218
• 12 Horswill C A. Weight loss and weight cutting in amateur wrestlers: implications for performance and resting metabolic rate.  Int J Sport Nutr. 1993;  3 245-260
• 13 Jackson A S, Pollok M L. Practical assessment of body composition.  Phys Sportsmed. 1985;  113 76-90
• 14 Kiningham R B, Gorenflo D W. Weight loss methods of high school wrestlers.  Med Sci Sports Exerc. 2001;  33 810-813
• 15 Koutedakis Y, Pacy P J, Quevedo R M, Millward D J, Hesp R, Boreham C, Sharp N C. The effects of two different periods of weight-reduction on selected performance parameters in elite lightweight oarswomen.  Int J Sports Med . 1994;  15 472-477
• 16 Montain S J, Smith S A, Mattot R P, Zientara G P, Jolesz F A, Sawka M N. Hypohydration effects on skeletal muscle performance and metabolism: a 31P-MRS study.  J Appl Physiol. 1998;  84 1889-1894
• 17 Nose H, Mack G W, Shi X, Nadel E R. Role of osmolality and plasma volume during rehydration in humans.  J Appl Physiol. 1990;  65 325-331
• 18 Oopik V, Paasuke M, Sikku T, Timpmann S, Medijainen L, Ereline J, Smirnova T, Gapejeva E. Effect of rapid weight loss on metabolism and isokinetic performance capacity. A case study of two well trained wrestlers.  J Sports Med Phys Fitness. 1996;  36 127-131
• 19 Oopik V, Paasuke M, Timpmann S, Medijainen L, Ereline J, Smirnova T. Effect of creatine supplementation during rapid body mass reduction on metabolism and isokinetic muscle performance capacity.  Eur J Appl Physiol. 1998;  78 83-92
• 20 Oppliger R A, Case H S, Horswill C A, Landry G L, Shelter A C. Amercian College of Sports Medicine position stand. Weight loss in wrestlers.  Med Sci Sports Exerc. 1996;  28 ix-xii
• 21 Ruiz J R, Mesa J LM, Gutiérrez A, Castillo M J. Hand size influences optimal grip span in women but not in men.  J Hand Surg (Am). 2002;  27A 897-901
• 22 Ryan A J, Bleiler T L, Carter J E, Gisolfi C V. Gastric emptying during prolonged cycling exercise in the heat.  Med Sci Sports Exerc. 1989;  21 51-58.
• 23 Ryan A J, Lambert G P, Shi X, Chang R T, Summers R W, Gisolfi C V. Effect of hypohydration on gastric emptying and intestinal absorption during exercise.  J Appl Physiol. 1998;  84 1581-1588
• 24 Scheett T P, Webster M J, Wagoner K D. Effectiveness of glycerol as a rehydrating agent.  Int J Sport Nutr. 2001;  11 63-71
• 25 Shi X, Gisolfi C V. Fluid and carbohydrate replacement during intermittent exercise.  Sports Med. 1998;  25 157-172
• 26 Smith M S, Dyson R, Hale T, Harrison J H, McManus P. The effects in humans of rapid loss of body mass on a boxing-related task.  Eur J Appl Physiol. 2000;  83 34-39
• 27 Stout J R, Eckerson J M, Housh T J, Johnson G O, Betts N M. Validity of percent body estimations in males.  Med Sci Sports Exerc. 1994;  26 632-636
• 28 Webster S, Rutt R, Weltman A. Physiological effects of a weight loss regimen practised by college wrestlers.  Med Sci Sports Exerc. 1990;  22 229-234