Overlaps of Skeletal Muscle Fatigue and Skeletal Muscle Damage: The Muscle Injury Continuum

Area of Science:

• Sports Medicine
• Exercise Physiology
• Biomechanics

Background:

• Muscle fatigue, traditionally linked to metabolic stress, and muscle damage, linked to mechanical overload, share overlapping physiological mechanisms.
• These include prolonged-force depression, enzyme leakage, and inflammatory responses, challenging a binary view of muscle injury.
• This review explores these overlaps, moving beyond traditional distinctions.

Purpose of the Study:

• To synthesize evidence on the physiological and mechanical overlaps between muscle fatigue and muscle damage.
• To introduce the concept of a muscle injury continuum, linking fatigue to tissue damage and severe injuries.
• To discuss the implications of these overlaps for load monitoring and injury prevention in professional sports.

Main Methods:

• Narrative review of existing scientific literature.
• Synthesis of evidence on shared mechanisms between muscle fatigue and damage.
• Discussion of the muscle injury continuum and its relevance to sports.

Main Results:

• Muscle fatigue and muscle damage are not distinct but exist on a continuum with overlapping mechanisms.
• Certain forms of muscle fatigue can initiate a cascade leading to mechanical tissue damage.
• The interplay between fatigue and damage is critical for understanding injury development.

Conclusions:

• Understanding the interplay between muscle fatigue and muscle damage is essential for effective injury prevention.
• Individualized strategies for load management and performance enhancement can be developed by recognizing these overlaps.
• This integrated approach is vital for athletes' long-term health and performance efficiency.