Objective
To investigate the biomechanic influence of body weight unloading on the hemiplegic gait and to provide database for producing optimal strategies of gait training through body weight unloading (BWU) in hemiplegic patients

Method
We evaluated dynamic electromyographic data, temporal parameters of gait, and energy consumption in 20 hemiplegic patients walking on a treadmill with 0%, 10%, 20%, 30% and 40% of their BWU at their comfortable walking speed.

Results
1) Stance phase and double limb support phase significantly decreased, and swing phase and single limb support phase increased according to BWU.

2) Asymmetricity of temporal parameters of gait improved according to BWU.

3) O₂ rate, O₂ cost, O₂ pulse and heart rate significantly decreased with increasing BWU.

4) Muscular activities of rectus femoris, vastus medialis and biceps femoris decreased at initial contact and first half of stance phase and activities of medial gastrocnemius significantly decreased during entire stance phase with increasing BWU.

Conclusion
BWU during treadmill locomotion would be advantageous as a therapeutic approach to retrain gait in hemiplegic patients.