POWER training in chronic stroke individuals: differences between responders and nonresponders

Area of Science:

• Neurology
• Rehabilitation Medicine
• Exercise Physiology

Background:

• Lower extremity muscle weakness is a major cause of dysfunction after stroke.
• Resistance training effectively addresses hemiparetic weakness and enhances walking.
• Identifying patient characteristics that predict improved walking speed post-training is crucial.

Purpose of the Study:

• To identify baseline characteristics and training responses associated with achieving a minimal clinically important difference (MCID) in walking speed after Post-stroke Optimization of Walking Using Explosive Resistance (POWER) training.
• To analyze which stroke survivors benefit most from POWER training in terms of gait improvement.

Main Methods:

• Seventeen participants underwent 24 sessions of POWER training, including leg presses, jump training, and fast walking.
• Outcome measures included Spatiotemporal Speed Walking (SSWS), Functional Capacity Walking Speed (FCWS), 6-Minute Walk Test (6-MWT), and knee power.
• Analysis focused on comparing responders (achieved MCID in SSWS) and non-responders.

Main Results:

• Responders showed significant improvements in SSWS, FCWS, 6-MWT, and both paretic and non-paretic knee power.
• Non-responders also demonstrated significant improvements in paretic and non-paretic knee power, despite not reaching the MCID for gait speed.

Conclusions:

• POWER training can enhance overall locomotor function in stroke survivors.
• Baseline paretic knee strength/power appears to be a key factor influencing individual response to this training regimen.
• The limited improvement in non-responders highlights that factors beyond lower extremity muscle power contribute to persistent locomotor dysfunction after stroke.