Muscle-fatigue sensor could help athletes train harder

A prototype system has been devised by Mohamed Al-Mulla, in PhD research at Essex University’s School of Computer Science and Electronic Engineering.

During training, athletes generally have to rely on their own perception of muscle fatigue — clinically defined as a reduction of the ability of a muscle to contract and exert force.

Localised muscle fatigue can be beneficial in promoting muscle growth or potentially harmful, causing strain and injury. Often it’s a fine line and timing is crucial, said Al-Mulla.

‘What I want to do is build a bridge between the brain and the muscle,’ he added.

‘When you go the gym, why do you do 10 reps of something? Why not more? Why not less? It’s quite arbitrary when you think about it. I train myself and sometimes I don’t even feel like doing three but I know I can do more.’

To acquire input data, the system uses surface-electromyography (sEMG) electrodes to detect electrical signals as muscles contract and a goniometer to measure kinematics as muscle fatigue can manifest itself as small oscillations or vibrations.