Intramuscular pathways of maladaptation in overtraining syndrome

Area of Science:

• Sports Medicine
• Exercise Physiology
• Skeletal Muscle Biology

Background:

• Progressive exercise training enhances athletic performance.
• Excessive training without adequate recovery can lead to overreaching and overtraining syndrome (OTS).
• Skeletal muscle dysfunction is a primary characteristic of OTS, impacting energy utilization and movement.

Purpose of the Study:

• To review the potential mechanisms underlying skeletal muscle impairments in overtraining syndrome (OTS).
• To explore parallels between OTS and chronic inflammatory/catabolic conditions for treatment insights.
• To discuss the utility of animal models in studying OTS pathophysiology.

Main Methods:

• Literature review focusing on skeletal muscle adaptations and maladaptations to exercise.
• Analysis of potential contributing factors: neural fatigue, endocrine dysregulation, mitochondrial dysfunction, oxidative stress, and inflammation.
• Comparison of OTS responses with chronic inflammatory and catabolic conditions.
• Discussion of animal models for controlled investigation of OTS.

Main Results:

• OTS involves complex skeletal muscle impairments.
• Key contributing factors include neural fatigue, hormonal imbalances, impaired mitochondrial function, oxidative stress, and systemic inflammation.
• Parallels exist between OTS and chronic inflammatory/catabolic states.

Conclusions:

• Skeletal muscle dysfunction is central to overtraining syndrome (OTS).
• Understanding the multifaceted mechanisms of OTS can inform treatment strategies.
• Animal models offer a valuable approach for further research into OTS complex pathophysiology.