Low-frequency percutaneous electrical stimulation is the application of an electrical current of <1000Hz through acupuncture needles located on the epineurium of the peripheral nervous system.

The hypothesis is that by placing the electrode, needle, closer to the nerve, a greater stimulation of the same will be achieved, thus being able to obtain greater effects. The goal is to determine if this technique has any effect on grip strength in the short term.

Single-blind randomized clinical trial of n = 12 healthy subjects. 4 assessments of the grip strength of the non-dominant hand will be made using a digital dynamometer, by a blinded investigator. A V0-pre-intervention, a V1-post-intervention, a V2 at 24 hours and a V3 at 10 days after the intervention. Subjects will be randomly assigned by EPIDAT 3.1, to an experimental group or a control group, with n = 6 each group. In the experimental group, an ultrasound-guided percutaneous electrical stimulation will be performed. With a pointer, a symmetrical biphasic low-frequency current of 10 Hz and 240 microseconds will be applied to the median nerve and ulnar nerve, until reaching the excitomotor threshold, with applications of 10 seconds and rests of 5 seconds until reaching a stimulation of 1 minute. total over each nerve. In the control group, the same invasive procedure will be performed, but no type of electrical stimulation will be applied.

Statistical analysis will be performed by another blinded assessor, using IBM SPSS Statistics 24. A two-factor ANOVA (intervention-time) with Bonferroni correction will be performed.

Inclusion Criteria:

• Healthy volunteers
• Ability to perform all clinical tests and understand the study process, as well as obtaining informed consent.
• Tolerance to the application of electrotherapy.
• That they have not diagnosed any pathology.
• They do not present a contraindication to puncture and / or the application of electric currents.

Exclusion Criteria:

• Neuromuscular disease.
• Epilepsy.
• Trauma, surgery or pain affecting the upper limb.
• Osteosynthesis material in the upper limb.
• Diabetes.
• Cancer.
• Cardiovascular disease.
• Pacemaker or other implanted electrical device.
• Take any drug (NSAIDs, corticosteroids, antidepressants, analgesics, antiepileptics, ...) during the study and in the previous 7 days.
• Presence of tattoos or other external agent introduced into the treatment or assessment area.
• Pregnancy