Effect of bMI on Lower Limb Muscle coactivation During Leg Strengthening exercises

The lower limb muscles and joints are major contributors for locomotion, body stability and weight bearing. The important Lower limb joints are Hip Joint, Knee joint and Ankle joint. Muscles attached with these joints control the joint movement. Simultaneous activation of muscles around the joint helps them to move and perform tasks. This coordinated activity of muscles is called Muscle Coactivation. There are factors affecting the stability of joints such as aging, body weight and pathology. The purpose of this work is to investigate the effect of Body Mass Index (BMI) in the lower limb muscle coactivation during Leg strengthening exercises. Agonist muscles are those that contribute major for a movement whereas antagonist muscles control or oppose the agonist action. Quadriceps-Hamstrings and Gastrocnemius-Tibialis anterior are the agonist-antagonist pairs that predominantly contribute towards knee joint and ankle joint movement and stability respectively. The Electromyogram (EMG) is a major tool for studying the muscle activity and function. Maximum Voluntary Contraction (MVC) for each muscle group is performed with a standard protocol where the contraction by the muscle group is obtained. The physical activities are chosen in such a way that it contributes towards individual muscle groups. EMG recorded during activity is normalised with the MVC and the coactivation between the agonist-antagonist pairs shall be obtained. This analysis helps in improving the exercise patterns for rehabilitation and can also be used in injury prevention programs.