Concentric and eccentric isokinetic lower extremity strength in persons with multiple sclerosis

Area of Science:

• Neurology
• Rehabilitation Medicine
• Exercise Physiology

Background:

• Clinicians hesitate to prescribe exercise for multiple sclerosis (MS) patients due to limited data on muscle performance.
• Understanding muscle torque capacity is crucial for developing effective rehabilitation strategies for MS.

Purpose of the Study:

• To compare the quadriceps and hamstrings muscle torque capacity between individuals with MS and matched non-MS controls.
• To investigate the effects of contraction type (concentric vs. eccentric) and speed on muscle torque in MS.

Main Methods:

• Nine individuals with MS and nine healthy controls underwent isokinetic dynamometry (KIN-COM II).
• Muscle torques were measured at various speeds during concentric (30-90°/sec) and eccentric (45-75°/sec) contractions.
• Peak torque was analyzed for quadriceps and hamstrings muscle groups.

Main Results:

• The non-MS group had higher peak torque, significantly so for concentric quadriceps contractions (p < .05).
• Both groups showed greater eccentric than concentric quadriceps torque, with significance in the MS group.
• The MS group experienced a greater torque decrease with increasing speed, especially during concentric contractions.

Conclusions:

• Individuals with MS demonstrate significant strength deficits, particularly in concentric muscle actions.
• Exercise programs emphasizing high-speed concentric strengthening may be beneficial for addressing strength impairments in MS.
• Further research is warranted to optimize exercise interventions for improving muscle function in MS.