Skeletal muscle mechanics: questions, problems and possible solutions

Area of Science:

• Biomechanics
• Human Movement Science
• Skeletal Muscle Physiology

Background:

• The sliding filament and cross-bridge theories revolutionized muscle mechanics, but fundamental questions remain regarding contraction mechanisms and properties.
• Despite historical advancements, a comprehensive understanding of skeletal muscle function and its mechanical properties in human movement is still lacking.

Purpose of the Study:

• To identify and discuss critical challenges in skeletal muscle mechanics.
• To propose potential solutions and highlight future research directions in the field.
• To focus on three key controversial and important areas: muscle contraction mechanisms, in vivo whole muscle mechanics, and synergistic muscle force-sharing.

Main Methods:

• This manuscript is a review and perspective piece, not presenting new experimental data.
• It synthesizes existing knowledge and identifies gaps in the understanding of muscle mechanics.
• The approach involves critically evaluating current theories and experimental evidence.

Main Results:

• Identifies significant unknowns in muscle contraction mechanisms.
• Highlights the need for further investigation into in vivo whole muscle mechanics and properties.
• Addresses the complex issue of force-sharing among synergistic muscles.

Conclusions:

• Significant challenges persist in fully understanding skeletal muscle contraction and mechanics.
• Further research is essential to elucidate in vivo muscle properties and function in human movement.
• Exploring muscle contraction mechanisms, in vivo properties, and force-sharing is crucial for advancing movement science and control.