Influence of Skeletal Muscle Glycogen on Passive Rewarming after Hypothermia,
Abstract
Individuals performing work and athletes competing in cold conditions may experience, in addition to muscle glycogen depletion, mild to moderate hypothermia. It has been hypothesized that muscle glycogen may provide the substrate for shivering thermogenesis. To examine the influence of muscle glycogen on the thermal responses to passive rewarming subsequent to mild hypothermia, eight subjects completed two cold (18 C) water immersions followed by 75 min of passive rewarming (24 C air, resting in blanket). The experiments followed several days of different exercise/diet regimens eliciting either low or normal prewarming muscle glycogen levels. Cold water immersion was performed for 180 min or to a rectal temperature T sub re of less than 35.5 C. Rewarming increased T sub re similarly during both LMG and NMG. Independent of treatment, afterdrop responses were evident only in those individuals (body fat < 15%) whose body core cooled during immersion supporting the contention that afterdrop is a function of the kinetics of heat flow through a mass of tissue. Furthermore, these data indicate that low muscle glycogen levels do not impair rewarming time nor alter afterdrop responses during passive rewarming following mild to moderate hypothermia. Keywords: Endurance(Physiology).
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1987
- Accession Number
- ADA186451
Entities
People
- Andrew J Young
- Michael N. Sawka
- P. D. Neufer
- Stephen R. Muza
Organizations
- United States Army Research Institute of Environmental Medicine