Effect of temperature on handgrip holding time.

Area of Science:

• Exercise Physiology
• Muscle Physiology
• Biophysics

Background:

• Muscle temperature is a critical factor influencing muscle function.
• Understanding the relationship between temperature and muscle endurance is vital for optimizing athletic performance and preventing injury.

Purpose of the Study:

• To investigate the impact of varying intramuscular temperatures on the sustained maximal voluntary contraction (MVC) handgrip holding time.
• To determine if elevated or reduced muscle temperatures affect handgrip endurance differently.

Main Methods:

• 12 college-age males participated in the study.
• Forearm and hand immersion in water baths set at 18°C, 35°C, or 45°C for 30 minutes to regulate intramuscular temperature.
• Participants performed a 70% MVC handgrip contraction, and holding time was recorded.

Main Results:

• Elevating intramuscular temperature to 45°C significantly reduced handgrip holding time compared to baseline (25.7 ± 6.2s vs. 38.3 ± 8.1s, P < 0.01).
• Reducing intramuscular temperature to 18°C did not significantly alter handgrip holding time (37.5 ± 9.4s vs. 38.3 ± 8.1s, N.S.).

Conclusions:

• Increased intramuscular temperature impairs muscle endurance, specifically reducing the holding time of sustained handgrip contractions.
• Thermoregulation strategies aimed at cooling muscles may not enhance, but rather maintain, handgrip endurance, while heating may be detrimental.