Potential role of passively increased muscle temperature on contractile function

Area of Science:

• Exercise Physiology
• Muscle Physiology
• Therapeutic Modalities

Background:

• Skeletal muscle function declines with aging, inactivity, and injury.
• Passive heating methods like hot baths and saunas are used for health and muscle treatment.
• Increased muscle temperature can positively affect muscle contraction properties.

Purpose of the Study:

• To review and discuss the role of acute passive heating on skeletal muscle contractile function.
• To highlight potential cellular mechanisms responsible for heating-induced improvements.
• To explore passive heating as a strategy for enhancing muscle performance and recovery.

Main Methods:

• Literature review of studies investigating passive heating and skeletal muscle function.
• Analysis of research on acute effects of increased muscle temperature on muscle properties.
• Synthesis of evidence regarding cellular mechanisms involved in passive heating response.

Main Results:

• Passive heating acutely increases muscle temperature, enhancing voluntary rate of force development.
• Electrically evoked contraction properties, including time to peak twitch torque and half-relaxation time, are improved.
• Reduced electromechanical delay is observed following passive heating interventions.

Conclusions:

• Acute passive heating can enhance skeletal muscle contractile function through peripheral mechanisms.
• Increased calcium kinetics, enhanced calcium sensitivity, and elevated intramuscular fluid are potential contributing factors.
• Passive heating presents a viable non-invasive method to improve muscle performance and aid in recovery across various populations.