KINEMATIC AND KINETIC ANALYSIS OF KNEE EXTENSION EXERCISE WHILE USING AN ACTIVE FOOTREST AMONG NORMAL-WEIGHT AND OBESE PARTICIPANTS

Through kinematic and kinetic analysis of the knee and ankle joints of the participants while using an active footrest (AFR), this study aimed to measure the external forces acting on these joints compared to the sitting position. It also sought to compare the loading of these forces between normal-weight and obese people. Twelve males (six normal-weight and six obese) aged 32–50 years (Median = 42.72, [Formula: see text] 1 – [Formula: see text] 3 = 39–46) volunteered to participate in the study. A two-dimensional kinematic analysis was performed using a camera and Kinovea-0.9.5 software. Simultaneously, the external forces acting on the joints while using AFR were measured using a researcher-made force measurement system. Finally, the moment (N. m) on the joints in a movement cycle of exercising with AFR was measured using a mathematical model and motion simulation by applying a sliding mode, created in MATLAB software. There was no significant difference in the amount of force and moment applied to the knee and ankle joints of the participants in two sitting and active positions ([Formula: see text] > 0.05). Whereas, unlike the ankle joints, the movement on the knee joints of the obese participants, while doing exercise with AFR, was significantly higher than the normal-weight participants ([Formula: see text] = 0.003). Moreover, the ROM of the joints showed no significant difference between the normal-weight and obese participants. Since no significant difference was observed in loads of two sitting and active positions (exercise with AFR) and given the significantly lower moment load of AFR compared to the treadmill and cycling desks, musculoskeletal disorders are less likely to develop when using AFR.