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Updated: Jun 30, 2026
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Early Weight-Bearing Rehabilitation Protocol After Anterior Cruciate Ligament Reconstruction
Published on: March 1, 2024
Slow or Fast lsokinetic Training after - Knee Ligament Surgery*
The Journal of Orthopaedic and Sports Physical Therapy
|January 1, 1987
Summary
Isokinetic training speed and dose effects on muscle morphology were studied in anterior cruciate ligament patients. Fast-speed training showed a tendency for greater strength gains at higher speeds and increased fast-twitch fiber size, though overall quadriceps growth was similar between groups.
Area of Science:
- Sports Medicine
- Orthopedics
- Muscle Physiology
Background:
- Anterior cruciate ligament (ACL) injuries often require rehabilitation to restore muscle function.
- Isokinetic training is a common modality, but optimal parameters like speed and dose are debated.
- Understanding training effects on muscle morphology is crucial for effective recovery protocols.
Purpose of the Study:
- To investigate the impact of different isokinetic training speeds (slow vs. fast) and training doses on muscle strength and morphology in ACL-injured patients.
- To compare the effects of high-volume (10x15 reps) versus moderate-volume (10x10 reps) training protocols.
Main Methods:
- 16 ACL-injured patients were randomized into two isokinetic training groups: slow speed (60°/sec) and fast speed (180°/sec).
- Training involved 8 weeks, 3 times per week, with specific repetition protocols (10x10 vs. 10x15).
- Evaluations included Cybex strength testing, muscle biopsies, and thigh muscle computed tomography.
Main Results:
- No significant overall differences in strength or quadriceps cross-sectional area between slow and fast speed groups.
- The fast-speed group exhibited a tendency for greater strength increases at higher velocities compared to the slow-speed group.
- A trend towards increased fast-twitch fiber cross-sectional area was observed in the fast-speed training group.
- Higher training volume (10x15 reps) did not result in greater strength gains compared to a lower volume (3x10 reps) in previous studies.
Conclusions:
- Isokinetic training speed may influence strength gains at specific velocities and muscle fiber adaptations, with faster speeds potentially favoring higher-velocity strength.
- Current training protocols, even with higher doses, may not significantly enhance overall muscle hypertrophy or strength beyond established parameters.
- Further research is needed to optimize isokinetic training parameters for ACL rehabilitation and muscle adaptation.