Muscle performance is largely influenced by modulations in gene expressions of muscle tissue. In this context, light-emitting diode therapy (LEDT) has been used to improve muscle performance in experimental models and human researches. Thereby, the investigators examined modulations in gene expression of muscle tissue as well as biochemical, biomechanic and histologic adaptations influenced by exercise associated to LEDT.

This study assessed muscle performance in isokinetic dynamometry and led press device, gene expression by RT-PCR, lactate, creatine kinase and morphology of muscle tissue by immunohistochemical analysis

Inclusion Criteria:

• healthy males aged between 18 and 28 years with a body mass index (BMI) equal to or less than 26 kg/m2,
• moderated pattern of physical activity

Exclusion Criteria:

• previous injury to the femoral quadriceps or hamstring muscles (within 6 months prior to study),
• osseous or articular disorder in the lower limbs,
• cardiovascular system disorders,
• systemic disease, and
• taking prescription medicines or using dietary supplements such as muscle mass builders.