Effect of Single-Session HVPGS on Hand Grip Strength and Reaction Time in Healthy Individuals

The aim of this cross-sectional study is to investigate the immediate (acute) effects of a single session of High-Voltage Pulsed Galvanic Stimulation (HVPGS) on hand muscle strength and reaction time in healthy adults. A total of 42 healthy volunteers aged 18 to 65 years undergo a single session of HVPGS applied to the forearm flexor muscles (m. flexor digitorum superficialis, m. flexor digitorum profundus, and m. flexor pollicis longus). Isometric hand grip strength is evaluated before (T0) and immediately after (T1) the intervention using a Jamar hand dynamometer. Sensorimotor reaction time is measured at the same time points using the Nelson Hand Reaction Test. The study aims to determine whether acute HVPGS application elicits immediate bilateral enhancements in mechanical force production and central-mediated processing speed, and whether these gains interact with demographic factors or hemispheric hand dominance.

Inclusion Criteria: Healthy academic and administrative staff, or senior physical therapy and rehabilitation students of Kırşehir Ahi Evran University. Aged between 18 and 65 years. Voluntary participation with signed written informed consent provided prior to enrollment. Exclusion Criteria: Self-reported elbow, hand, shoulder, or neck discomfort in the past 6 months. Presence of active upper extremity pain. Neurological disorders affecting upper extremity sensation or motor execution.