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Updated: Jul 26, 2026
08:42
Myo-mechanical Analysis of Isolated Skeletal Muscle
Published on: February 22, 2011
Thermal effects on skeletal muscle tensile behavior
T J Noonan1, T M Best, A V Seaber
1Orthopaedic Research Laboratories, Duke University Medical Center, Durham, North Carolina 27710.
The American Journal of Sports Medicine
|July 1, 1993
Summary
Warming rabbit skeletal muscles significantly impacts their mechanical properties, increasing failure load and energy absorption. Cold muscles demonstrated superior tensile strength and stiffness, suggesting temperature influences injury prevention and athletic performance.
Area of Science:
- Biomechanics
- Muscle Physiology
- Thermal Effects on Tissues
Background:
- Skeletal muscle mechanical properties are crucial for athletic performance and injury prevention.
- Understanding the influence of temperature on muscle tissue is essential for optimizing training and rehabilitation strategies.
Purpose of the Study:
- To investigate the effect of temperature on the mechanical failure properties of rabbit skeletal muscle.
- To determine how loading rate and contractile state interact with temperature to affect muscle tensile properties.
Main Methods:
- Rabbit tibialis anterior and extensor digitorum longus muscles were tested at two temperatures: 25°C (cold) and 40°C (warm).
- Muscles were subjected to passive failure at loading rates of 1 cm/sec and 10 cm/sec, or active failure at 10 cm/sec with electrical stimulation.
- Mechanical parameters including load to failure, total deformation, energy absorbed, and stiffness were measured.
Main Results:
- Cold muscles consistently exhibited higher load to failure across all tested conditions.
- Energy absorbed before failure was greater in cold muscles at slower loading rates and during active contraction.
- Stiffness was generally higher in cold muscles, with some exceptions noted for the extensor digitorum longus at a passive 10 cm/sec loading rate.
- Warm muscles tested at 10 cm/sec showed higher failure loads than those tested at 1 cm/sec.
- Stimulated muscles absorbed more energy and had higher failure loads and stiffness compared to unstimulated muscles.
Conclusions:
- Temperature significantly affects the tensile properties of skeletal muscle.
- Thermal effects on muscle mechanics are dependent on loading rate and contractile state.
- Warming muscles may enhance performance and contribute to injury prevention, supported by experimental data on increased failure load and energy absorption.
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