The effects of training intensities on motor recovery and gait symmetry in a rat model of ischemia

Abstract

Primary objective: This study investigated the effects of moderate and excessive gait training intensities on motor recovery in sub-acute stroke.

Methods: Sprague-Dawley rats after stroke surgery were randomized into two groups: moderate training group (MTG) and excessive training group (ETG). MTG had 15 minutes of body weight support (BWS) treadmill training per session with three sessions per day on alternative days until 8 days after stroke; and in the ETG, rats had to run until they could not keep up with the treadmill speed for one session on each training day. The intramuscular EMG signal from medial gastrocnemius was used to monitor the muscle activation patterns on both unaffected and affected sides during training.

Results: After 4 days post-stroke, the results showed a better recovery in the symmetry gait pattern in the MTG, but there is no such trend observed in the ETG. Moreover, the MTG has a better motor behaviour score and the affected side could bear more body weight. These results were reflected in the increase in the EMG burst duration and increase in EMG mean power frequency (MPF) drop rate on the affected side in the MTG.

Conclusion: This study shows the moderate gait training intensity by avoiding muscular fatigue has better motor recovery for sub-acute stroke rehabilitation.

• Training intensities
• electromyography
• stroke
• motor recovery

Abbreviations
BWS	=	body weight support
ETG	=	excessive training group
MTG	=	moderate training group
EMG	=	electromyography
MPF	=	mean power frequency
MG	=	medial gastrocnemius
FFT	=	fast Fourier transform
SI	=	symmetry index.

Abbreviations
BWS	=	body weight support
ETG	=	excessive training group
MTG	=	moderate training group
EMG	=	electromyography
MPF	=	mean power frequency
MG	=	medial gastrocnemius
FFT	=	fast Fourier transform
SI	=	symmetry index.