Six 30-pulse trains of 20 Hz repetitive Transcranial Magnetic Stimulation to left primary motor cortex hand area, separated by 60 seconds, repeated at 0, 24, 48, and 72 hours post-immobilisation.

Six 30-pulse trains of 20 Hz repetitive sham Transcranial Magnetic Stimulation above, but not in contact with, the head, separated by 60 seconds, repeated at 0, 24, 48, and 72 hours post-immobilisation.

TMS is a safe and non-invasive technique, which involves the generation of brief magnetic pulses applied to the head through a coil. The magnetic pulses pass through the scalp and skull and induce weak electric currents in the neural tissue directly underneath the coil. When TMS is applied in repetitive, patterned trains of pulses (rTMS), it can induce cortical plasticity specifically in the targeted brain region.

MEPs are elicited via TMS to primary motor cortex and index the excitability of the motor pathway. They are recorded non-invasively from muscles using surface electrodes. At each time point of the study (0, 24, 48, 72 hours) record MEPs will be recorded pre and post-intervention from the hand muscles of the dominant (immobilised) arm, and non-dominant (non-immobilised arm), to evaluate changes in excitability. Specifically, the peak-to-peak value of the MEPs from the hand will be measured, which reflects the amplitude of the MEP response. The latency of the MEP to index neural conduction speed will also be measured.

Grip strength of the dominant and non-dominant hands will be assessed using an isokinetic dynamometer at 0 and 72 hrs post-immobilisation. This will measure the strength of the hand muscles.