Accession Number : AD0655069

Title :   THE COMBINED EFFECTS OF COLD AND EXERCISE ON THE TRICEPS SURAE REFLEX,

Corporate Author : ARCTIC AEROMEDICAL LAB FORT WAINWRIGHT ALASKA

Personal Author(s) : Petajan,Jack H. ; Eagan,Charles J.

Report Date : MAY 1967

Pagination or Media Count : 20

Abstract : The one-half relaxation time (1/2 RT) for the triceps surae reflex was studied in four subjects after five-minute runs at 134 m/min (5 mi/hr) on a treadmill set at 10% grade. This exercise decreased 1/2 RT to 90% of normal. Cooling by immersion to the neck for 60 min in a stirred 30C bath enhanced the exercise effect on 1/2 RT (decreased it to 87%) whereas cooling alone lengthens the relaxation phase. Eight highly-fit athletes (U. S. Biathlon Team) who exercised at the higher level of 5 min at 188 m/min (7 mi/hr) and 8.6% grade, showed a greater effect on 1/2 RT: a decrease to 83% of the pre-exercise value. The shortening of relaxation time by exercise appears to be a warm-up phenomenon related to local metabolic changes in muscle which, paradoxically, are enhanced by whole-body cooling. (Author)

Descriptors :   (*MUSCLES, REFLEXES), EXERCISE(PHYSIOLOGY), COOLING, BODY TEMPERATURE, NEUROMUSCULAR TRANSMISSION, METABOLISM, PHYSICAL FITNESS, RELAXATION TIME

Subject Categories : Personnel Management and Labor Relations
      Anatomy and Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE