Related Experiment Videos
Plasma aldosterone and sweat sodium concentrations after exercise and heat acclimation
Journal of Applied Physiology (Bethesda, Md. : 1985)
|September 1, 1986
Summary
Heat acclimation reduces plasma aldosterone levels and enhances eccrine sweat gland sodium reabsorption during exercise. This improves the body's ability to conserve sodium in hot environments.
Area of Science:
- Exercise Physiology
- Environmental Physiology
- Human Adaptation
Background:
- Heat acclimation is crucial for thermoregulation and electrolyte balance.
- Eccrine sweat glands play a key role in sodium excretion and conservation.
- Aldosterone influences sodium reabsorption in sweat glands.
Purpose of the Study:
- To investigate the relationship between plasma aldosterone and eccrine sweat gland sodium excretion after heat acclimation.
- To determine how exercise and heat exposure affect these physiological parameters.
Main Methods:
- Ten subjects underwent 10 days of daily exercise in a hot environment.
- Measurements included plasma aldosterone, sweat sodium concentration and excretion, and sweat rate.
- Physiological markers of acclimation (heart rate, temperature, plasma volume) were assessed.
Main Results:
- Heat acclimation led to decreased plasma aldosterone concentrations.
- Sweat sodium concentration and total sodium excretion were significantly reduced.
- The ratio of sweat sodium reabsorbed to plasma aldosterone increased, indicating enhanced gland responsiveness.
Conclusions:
- Plasma aldosterone levels decrease with heat acclimation.
- Eccrine sweat gland responsiveness to aldosterone, measured by sodium reabsorption, is augmented by exercise and heat acclimation.
- This suggests an improved mechanism for sodium conservation in heat-exposed individuals.