The effect of isolating the paretic limb on weight-bearing distribution and EMG activity during squats in hemiplegic and healthy individuals.
BACKGROUND
Neural reorganization for movement therapy after a stroke is thought to be an important mechanism that facilitates motor recovery. However, there is a lack of evidence for the effectiveness of exercise programs in improving the lower limbs.


OBJECTIVE
We investigated the immediate effect of isolating the paretic limb using different foot positions ((i) foot parallel; both feet parallel, (ii) foot asymmetry; paretic foot backward by 10 cm, and (iii) foot lifting; nonparetic foot lifting by normalization to 25% of knee height) on weight-bearing distribution and electromyography (EMG) of the thigh muscle during squats.


METHODS
In total, 20 patients with hemiplegia and 16 healthy subjects randomly performed three squat conditions in which the knee joint was flexed to 30°. Weight distribution was measured using the BioRescue system. Muscle activity was measured using a surface EMG system.


RESULTS
Patients with hemiplegia exhibited significantly decreased weight bearing on the paretic foot at 0° and 30° knee flexion compared with the nondominant foot of a healthy subject. The muscle activity of the quadriceps was significantly lower in patients with hemiplegia compared to healthy subjects. Weight bearing and EMG activity of the quadriceps femoris on the paretic or nondominant side significantly increased during a knee flexion of 30° with under the foot asymmetry and foot lifting positions compared with the parallel foot position.


CONCLUSION
Isolating the paretic limb using the asymmetric foot positions and lifting of the foot during squats might help patients with hemiplegia to improve weight-bearing and achieve greater activation of the quadriceps muscle in the paretic limb.
['Lee|Dong-Kyu|DK|', 'An|Duk-Hyun|DH|', 'Yoo|Won-Gyu|WG|', 'Hwang|Byong-Yong|BY|', 'Kim|Tae-Ho|TH|', 'Oh|Jae-Seop|JS|']
D000328:Adult D000368:Aged D001696:Biomechanical Phenomena D004576:Electromyography D005081:Exercise Therapy D005260:Female D006429:Hemiplegia D006801:Humans D007719:Knee Joint D035002:Lower Extremity D008297:Male D008875:Middle Aged D052097:Quadriceps Muscle D020521:Stroke D000071939:Stroke Rehabilitation
isolating the paretic limb weight-bearing distribution squat Electromyography