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Mode and speed specificity of eccentric and concentric exercise training.
The Journal of Orthopaedic and Sports Physical Therapy
|January 1, 1989
Summary
Eccentric isokinetic exercise significantly enhances eccentric quadriceps strength at all speeds, while concentric training shows limited specific gains. Exercise speed did not appear to affect training specificity.
Area of Science:
- Sports Science
- Exercise Physiology
- Biomechanics
Background:
- Strength training specificity is crucial for optimizing performance and rehabilitation.
- Isokinetic exercise allows for controlled assessment of muscle force production.
- Understanding the distinct effects of concentric and eccentric contractions is vital.
Purpose of the Study:
- To investigate the mode specificity of strength training.
- To compare the effects of concentric versus eccentric isokinetic exercise on quadriceps strength.
- To determine if exercise speed influences training specificity.
Main Methods:
- Forty-eight healthy men were divided into concentric training, eccentric training, and control groups.
- Isokinetic dynamometry assessed quadriceps force at 60, 120, and 180 degrees/sec before and after a 6-week training intervention.
- Training involved maximal effort isokinetic contractions at 120 degrees/sec, focusing solely on concentric or eccentric actions.
Main Results:
- Eccentric training group demonstrated significant gains in eccentric quadriceps force across all tested speeds.
- Concentric training group showed significant improvements in concentric force only at 180 degrees/sec.
- Control group exhibited no significant changes in force production.
Conclusions:
- The eccentric mode of isokinetic exercise yields highly specific strength training adaptations.
- Concentric isokinetic training exhibits less specificity in strength gains.
- Exercise speed does not appear to be a significant factor in the specificity of isokinetic strength training.
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