15 participants will be included in the present study. They will attend two groups of three sessions (i.e. sessions 1-2-3 and sessions 4-5-6) spaced by 3 months:

• session 1 and 4 (performed a few days before the experimental session): session for participants to get familiarized with the test battery.
• session 2 and 5: experimental session (the test battery followed by the provocative task, the test battery, the one-hour "treatment" and the test battery again).
• session 3 and 6 (performed 2 days later): the test battery.

The test battery included flexibility, functional, pressure pain threshold tests.

The provocative task was an isokinetic eccentric task for knee flexors and extensors.

The treatment was either a microcurrent therapy or a placebo microcurrent therapy.

Objective:

To study the efficacy of microcurrent to reduce DOMS (Delayed Onset Muscle Soreness) occuring after an eccentric exercise

Methods:

Experimental protocol

Participants will attend two groups of three sessions (i.e. sessions 1-2-3 and sessions 4-5-6) spaced by 3 months:

• session 1 and 4 (performed a few days before the experimental session): session for participants to get familiarized with the test battery.
• session 2 and 5: experimental session: the test battery followed by the provocative task, the test battery, the one-hour "treatment" (real microcurrents at one of the session and placebo microcurrents at the other one) and the test battery again.
• session 3 and 6 (performed 2 days later): the test battery.

Before starting session 2, patients will be randomized into the microcurrent group or the placebo microcurrent group. Three months later, participants will change of group.

The Test Battery: it will be conducted by a blind (to the treatment) investigator. It will include knee flexor and extensor flexibility tests, a functional test (unilateral " counter-movement jump "), a pain to measure pain threshold of thigh muscles and an isometric maximal voluntary contraction (MVC) test of knee flexors and extensors.

The Provocative task: 40 isokinetic eccentric contractions of knee flexors and extensors.

The one-hour Treatment: with the participant lying on an examination table, several electrodes were located over the muscles involved in the provocative task. The microcurrent therapy was then started. It was stopped after 5 seconds in the "Placebo group" and after one hour in the real "Microcurrent group". The microcurrents were delivered by the machine B-E-St®.

Follow-up: in addition to the 48hours follow-up (session 3/6), participants will fill in a pain visual analogue scale each day after the session 2/5.

Inclusion Criteria:

• Asymptomatic subjects

Exclusion Criteria:

• practice of sports >3h per week
• present pain in the lower limbs
• history of thigh muscle injuries
• recent injury (last 3 months) of the lower limbs
• recent (last 3 months) plyometric exercises or lower limbs strengthening program.