Metabolic, thermoregulatory, and perceptual responses during exercise after lower vs. whole body precooling.

The purpose of this investigation was to compare the thermoregulatory, metabolic, and perceptual effects of lower body (LBI) and whole body (WBI) immersion precooling techniques during submaximal exercise. Eleven healthy men completed two 30-min cycling bouts at 60% of maximal O(2) uptake preceded by immersion to the suprailiac crest (LBI) or clavicle (WBI) in 20 degrees C water. WBI produced significantly lower rectal temperature (T(re)) during minutes 24-30 of immersion and lower T(re), mean skin temperature, and mean body temperature for the first 24, 14, and 16 min of exercise, respectively. Body heat storage rates differed significantly for LBI and WBI during immersion and exercise, although no net differences were observed between conditions. For WBI, metabolic heat production and heart rate were significantly higher during immersion but not during exercise. Thermal sensation was significantly lower (felt colder) and thermal discomfort was significantly higher (less comfortable) for WBI during immersion and exercise. In conclusion, WBI and LBI attenuated T(re) increases during submaximal exercise and produced similar net heat storage over the protocol. LBI minimized metabolic increases and negative perceptual effects associated with WBI.

[1]  M. Sawka,et al.  Human thermoregulatory responses during serial cold-water immersions. , 1998, Journal of applied physiology.

[2]  S. Davis,et al.  Effect of precooling on physical performance in multiple sclerosis , 2000, Multiple sclerosis.

[3]  T. Reilly,et al.  Investigation of the effects of the pre-cooling on the physiological responses to soccer-specific intermittent exercise , 2000, European Journal of Applied Physiology.

[4]  Y Epstein,et al.  Role of surface area-to-mass ratio and work efficiency in heat intolerance. , 1983, Journal of applied physiology: respiratory, environmental and exercise physiology.

[5]  K. Brück,et al.  Thermoregulatory, cardiovascular, and muscular factors related to exercise after precooling. , 1988, Journal of applied physiology.

[6]  N. Ramanathan,et al.  A NEW WEIGHTING SYSTEM FOR MEAN SURFACE TEMPERATURE OF THE HUMAN BODY. , 1964, Journal of applied physiology.

[7]  F. Plum.  Handbook of Physiology. , 1960 .

[8]  K. Pandolf,et al.  Thermal and metabolic responses to cold-water immersion at knee, hip, and shoulder levels. , 1997, Journal of applied physiology.

[9]  I. Jacobs,et al.  Muscle glycogen utilization during shivering thermogenesis in humans. , 1988, Journal of applied physiology.

[10]  B. Ekblom,et al.  Physical performance and peak aerobic power at different body temperatures. , 1979, Journal of applied physiology: respiratory, environmental and exercise physiology.

[11]  J. Booth,et al.  Improved running performance in hot humid conditions following whole body precooling. , 1997, Medicine and science in sports and exercise.

[12]  A. C. Burton,et al.  Human CalorimetryII. The Average Temperature of the Tissues of the Body: Three Figures , 1935 .

[13]  S. Davis,et al.  Thermal regulatory responses to submaximal cycling following lower-body cooling in humans , 2002, European Journal of Applied Physiology.

[14]  A B DuBois,et al.  Thermal discomfort of respiratory protective devices. , 1990, American Industrial Hygiene Association journal.

[15]  I. Holmér.  Body cooling with ice for warm-water diving operations. , 1989, Undersea biomedical research.

[16]  V. Arora,et al.  Quantum freeze‐out effect in a size‐limited intrinsic transport , 1983 .

[17]  J. B. Weir.  New methods for calculating metabolic rate with special reference to protein metabolism , 1949, The Journal of physiology.

[18]  V. Star Campbell,et al.  Exercise Physiology: Energy, Nutrition, and Human Performance, 3rd Edition, W. McArdle, F. Katch, V. Katch. From Lea and Febiger, 200 Chester Field Parkway, Malvern, PA 19355-9725 (1991), 853 pp., hardcover, $47.50., ISBN: 0-8121-1351-9 , 1992 .

[19]  D. Baker.  Multiple sclerosis and thermoregulatory dysfunction. , 2002, Journal of applied physiology.

[20]  V. Hessemer,et al.  Effect of slightly lowered body temperatures on endurance performance in humans. , 1984, Journal of applied physiology: respiratory, environmental and exercise physiology.

[21]  D. Costill,et al.  Effects of precooling on thermoregulation during subsequent exercise. , 1999, Medicine and science in sports and exercise.

[22]  Kim Jk,et al.  Peripheral blood flow and heat flux of Korean women divers. , 1969 .

[23]  Ethan R. Nadel,et al.  Problems with temperature regulation during exercise , 1977 .

[24]  D. T. Lee,et al.  Exercise duration and thermoregulatory responses after whole body precooling. , 1995, Journal of applied physiology.

[25]  J. Petajan,et al.  Impact of aerobic training on fitness and quality of life in multiple sclerosis , 1996, Annals of neurology.