These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Run performance of middle-aged and young adult runners in the heat.
    Author: de Paula Viveiros J, Amorim FT, Alves MN, Passos RL, Meyer F.
    Journal: Int J Sports Med; 2012 Mar; 33(3):211-7. PubMed ID: 22161295.
    Abstract:
    The aging process may impair exercise tolerance in the heat. It is not clear whether this impairment is partly due to a reduction in aerobic capacity. To compare the exercise performance and thermoregulatory responses of middle-aged and young adults with similar aerobic capacities and training statuses, 7 middle-aged (54±2 years; 58±4 ml·kg - 1·min - 1) and 7 young (28±1 years; 61±5 ml·kg - 1·min - 1) male competitive endurance runners underwent 2 10-km self-paced and 2 fixed-workload (90% of race speed) runs until fatigue on a treadmill in hot (40°C) and moderate (20°C) environments on separate days. The runners' total time, average speed, rectal temperature, heat storage rate, physiological strain index, sweat rate, sweat sensitivity, number of heat-activated sweat glands and sweat rate per sweat gland were measured or calculated. Body fat, body surface area, body surface area per body mass, training volume and VO2max were similar between the 2 groups. No differences were observed in total time (59±3; 49±3; 27±2; 54±5 min in the middle-aged and 60±2; 49±3; 27±2; 51±4 min in the young group), average speed, rectal temperature, heat storage rate, physiological strain index, sweat rate (17±7; 15±3; 23±7; 13±2 g.m - 2.min - 1 in the middle-aged and 20±5; 14±4; 22±5; 15±4 g.m - 2.min - 1 in the young group) or sweat sensitivity between age groups (p>0.05) in any trial. The number of heat-activated sweat glands (88±14; 80±18; 90±16; 66±14 cm - 2 in the middle-aged and 43±10; 32±10; 37±11; 31±11 cm - 2 in the young group) was higher, and the sweat rate per sweat gland was smaller, in the middle-aged than the young group (p<0.05) in all of the trials. We conclude that running performance and body thermoregulation are similar between young and middle-aged runners with similar aerobic capacities and training statuses under hot and moderate conditions in self-paced and fixed-intensity runs. The decrease observed in the sweat rate per sweat gland in middle-aged men was compensated for by a higher number of heat-activated sweat glands.
    [Abstract] [Full Text] [Related] [New Search]