The influence of exercise and dehydration on postural stability

Area of Science:

• Exercise Physiology
• Sports Science
• Human Performance

Background:

• Postural balance is crucial for athletic performance and injury prevention.
• Dehydration, whether from exercise or heat, can potentially impair physiological functions.
• Understanding the specific effects of different dehydration types on balance is important for athletes and trainers.

Purpose of the Study:

• To investigate the impact of exercise-induced dehydration on postural balance.
• To compare the effects of fluid replacement versus no fluid intake during prolonged exercise.
• To examine the influence of thermal dehydration on postural stability.

Main Methods:

• Eight male subjects performed 2-hour cycling trials at 57-63% VO2max, with and without a carbohydrate-electrolyte solution.
• Postural balance was assessed using center of pressure (COP) excursion velocity on a force platform before and after exercise.
• Eight subjects underwent seven 15-minute sauna sessions to induce thermal dehydration without fluid replacement.

Main Results:

• Exercise without fluid ingestion significantly increased COP excursion velocity, indicating reduced postural stability.
• Fluid replacement during exercise prevented the negative effects on postural balance.
• Thermal dehydration, resulting in a 3.0% body mass loss, did not significantly affect postural stability.

Conclusions:

• Prolonged exercise without adequate fluid intake negatively impacts postural stability.
• Maintaining hydration during exercise is essential for preserving postural control.
• Thermal dehydration, under the conditions studied, does not appear to compromise postural balance.