['The cutaneous silent period (CSP) is a spinal inhibitory reflex mediated by A-delta fibers. The amount of muscle contraction has been reported to influence CSPs, but this has not been confirmed in studies applying clinically feasible stimulus parameters.', 'Fourteen healthy subjects underwent comparison of CSPs while contracting the target muscle at different levels ranging from 10% to 50% of the maximum force, which was continuously monitored with a force transducer. Rectified surface electromyographic (EMG) recordings were obtained from abductor pollicis brevis muscle following ipsilateral recurrent noxious digit 2 and digit 5 stimulation.', 'Group average CSP onset and end latency, CSP duration, and the magnitude of EMG suppression were not influenced by volitional muscle contraction ranging from 10% to 50% of the maximum. In contrast, background EMG levels increased significantly with the amount of muscle force.'] Does muscle force up to 50 % of maximum affect cutaneous silent periods in thenar muscles?