Proprioceptive Neuromuscular Facilitation (PNF) is a concept that has been applied to treating numerous disabling disorders. Among the basic PNF procedures, there is motor irradiation, in which resistance is applied to a body segment to generate muscle activation in another segment and thus obtain improvement in muscle strength. The generated muscular activation can be analyzed in several ways, one of them being Electromyography (EMG). Electromyographic analysis has suggested that target muscles of irradiation demonstrate electromyographic activity during irradiation in healthy individuals and in those with neurological disorders. Despite this, the neuromuscular activation profile (amplitude and temporality) resulting from the different stimuli and positions used in PNF has not yet been investigated.

To analyze the neuromuscular activation profile of upper limb muscles in healthy individuals during the application of different PNF irradiation protocols.

This is a cross-sectional study in which 32 healthy individuals of both sexes, aged between 18 and 45 years. After signing the consent form, the handedness of a subject in activities of daily living, level of physical activity, and sociodemographic characteristics will be identified. First, the EMG signals of the upper limb muscles (biceps brachii, brachioradialis, flexor carpi radialis, and triceps) will be collected during a maximum voluntary contraction (3 repetitions held for 3s with an interval of 30s between contractions). Then, the EMG signal of these muscles of the non-preferential limb will be collected, during 4 PNF irradiation techniques in a randomized order for each participant. Each irradiation will be applied 3 times, maintaining the contraction for 5s, with a 10s interval between them. After each irradiation will be checked the perceived exertion.

The study is in the data collection phase.

It is expected through this study to verify if the applied irradiation techniques activate the musculatures described anecdotally in the clinical literature.

The study can generate an understanding of motor irradiation and the use of the technique to improve the strength of a body segment.