Age-related differences in the neuromuscular performance of fatigue-provoking exercise under severe whole-body hyperthermia conditions.
Scand J Med Sci Sports
; 33(9): 1621-1637, 2023 Sep.
Article
in En
| MEDLINE
| ID: mdl-37218443
ABSTRACT
PURPOSE:
The purpose of this study was to determine if aging would lead to greater decline in neuromuscular function during a fatiguing task under severe whole-body hyperthermia conditions.METHODS:
Twelve young (aged 19-21 years) and 11 older (aged 65-80 years) males were enrolled in the study, which comprised a randomized control trial under a thermoneutral condition at an ambient temperature of 23°C (CON) and an experimental trial with passive lower body heating in 43°C water (HWI-43°C). Changes in neuromuscular function and fatigability, and physical performance-influencing factors such as psychological, thermoregulatory, neuroendocrine, and immune responses to whole-body hyperthermia were measured.RESULTS:
A slower increase in rectal temperature, and a lower heart rate, thermal sensation, and sweating rate were observed in older males than young males in response to HWI-43°C trial (p < 0.05). Nevertheless, prolactin increased more in response to hyperthermia in young males, while interleukin-6 and cortisol levels increased more in older males (p < 0.05). Peripheral dopamine levels decreased in older males and increased in young males in response to hyperthermia (p < 0.05). Surprisingly, older males demonstrated greater neuromuscular fatigability resistance and faster maximal voluntary contraction (MVC) torque recovery after a 2-min sustained isometric MVC task under thermoneutral and severe hyperthermic conditions (p < 0.05).CONCLUSION:
Neuromuscular performance during fatigue-provoking sustained isometric exercise under severe whole-body hyperthermia conditions appears to decline in both age groups, but a lower relative decline in torque production for older males may relate to lower psychological and thermophysiological strain along with a diminished dopamine response and prolactin release.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Prolactin
/
Hyperthermia, Induced
Type of study:
Clinical_trials
Limits:
Aged
/
Humans
/
Male
Language:
En
Journal:
Scand J Med Sci Sports
Journal subject:
MEDICINA ESPORTIVA
Year:
2023
Type:
Article
Affiliation country:
Lithuania