Impact of muscle injury and accompanying inflammatory response on thermoregulation during exercise in the heat
Autor: | William A. Latzka, Michael N. Sawka, Scott J. Montain |
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Rok vydání: | 2000 |
Předmět: |
Adult
Male medicine.medical_specialty Hot Temperature Adolescent Physiology Acclimatization Pain Sweating Inflammation Physical exercise Body Temperature Heat illness Stress Physiological Physiology (medical) Internal medicine medicine Humans Eccentric Exercise physiology Treadmill Muscle Skeletal Creatine Kinase Exercise Aged Aged 80 and over Myositis Interleukin-6 Chemistry Middle Aged Thermoregulation medicine.disease Endocrinology Anesthesia Wounds and Injuries Female medicine.symptom Body Temperature Regulation Muscle contraction |
Zdroj: | Journal of Applied Physiology. 89:1123-1130 |
ISSN: | 1522-1601 8750-7587 |
Popis: | This study examined whether muscle injury and the accompanying inflammatory responses alter thermoregulation during subsequent exercise-heat stress. Sixteen subjects performed 50 min of treadmill exercise (45–50% maximal O2 consumption) in a hot room (40°C, 20% relative humidity) before and at select times after eccentric upper body (UBE) and/or eccentric lower body (LBE) exercise. In experiment 1, eight subjects performed treadmill exercise before and 6, 25, and 30 h after UBE and then 6, 25, and 30 h after LBE. In experiment 2, eight subjects performed treadmill exercise before and 2, 7, and 26 h after LBE only. UBE and LBE produced marked soreness and significantly elevated creatine kinase levels ( P < 0.05), but only LBE increased ( P < 0.05) interleukin-6 levels. In experiment 1, core temperatures before and during exercise-heat stress were similar for control and after UBE, but some evidence for higher core temperatures was found after LBE. In experiment 2, core temperatures during exercise-heat stress were 0.2–0.3°C ( P < 0.05) above control values at 2 and 7 h after LBE. The added thermal strain after LBE ( P < 0.05) was associated with higher metabolic rate ( r = 0.70 and 0.68 at 2 and 6–7 h, respectively) but was not related ( P > 0.05) to muscle soreness ( r = 0.47 at 6–7 h), plasma interleukin-6 ( r = 0.35 at 6–7 h), or peak creatine kinase levels ( r = 0.22). Local sweating responses (threshold core temperature and slope) were not altered by UBE or LBE. The results suggest that profuse muscle injury can increase body core temperature during exercise-heat stress and that the added heat storage cannot be attributed solely to increased heat production. |
Databáze: | OpenAIRE |
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