During the familiarization session with the exercise equipment, proper lifting technique will be demonstrated for knee extension exercise. A guided-motion exercise machine will be used to promote proper form and for the subject's personal safety. Prior to the determination of the subject's one repetition maximum (1RM), they will perform 2 sets of leg extension exercise for 10 repetitions on the exercise machine at a light load. Thereafter, the load will be increased after each successful lift until failure. 5 min rest periods will be allowed between attempts. A repetition is valid if the subject uses proper form and is able to complete the entire lift in a controlled manner without assistance.