Competitive soccer engages many of the body's systems to a major extent. The musculoskeletal, nervous, immune and metabolic systems are stressed to a point where recovery strategies post-exercise become influential in preparing for the next match.

Recovery from exercise can be an important factor in performance during repeated bouts of exercise. In a tournament situation, where athletes may compete numerous times over a few days, enhancing recovery may provide a competitive advantage. Recent work has highlighted that the aim of most recovery interventions is to return psychological, physiological, and performance variables to the 'pre-exercise' level or to baseline conditions identified in the absence of fatigue.

The post-exercise cold water immersion (CWI) through its primary ability to decrease tissue temperature and blood flow, is purported to facilitate recovery by ameliorating hyperthermia and subsequent alterations to the central nervous system (CNS), reducing cardiovascular strain, removing accumulated muscle metabolic by-products, attenuating exercise-induced muscle damage (EIMD) and improving autonomic nervous system function. All these alterations provoke important physiological changes for the recovery of the athlete.

Scientific evidence for other strategies reviewed in their ability to accelerate the return to the initial level of performance is still lacking. These include active recovery, stretching, compression garments, massage and electrical stimulation. While this does not mean that these strategies do not aid the recovery process, the protocols implemented up until now do not significantly accelerate the return to initial levels of performance in comparison with a control condition.

Among these new strategies, Photobimodulation therapy - PBMT using low-level laser therapy (LLLT) and light-emitting diode therapy (LEDT) has been the focus of important research insights science in recent years. The PBMT has been used to increase muscle performance and reduces muscle fatigue signals. The mechanism proposed for the use of PBMT in sports and exercise is the increase in cytochrome c-oxidase in skeletal muscle fibers that lead to upregulation of mitochondrial activity, which increases ATP production promoting more energy for the muscle and decreases oxidative stress and reactive oxygen species production.

Considering that the consented CWI is already used with good results in soccer athletes, however it has some drawbacks such as the time of application and the inconvenience caused by the application of cold and the new possibilities presented in the literature of the use of PBMT we propose to carry out this study. To address these issues, the present study aims to investigate and analyze biological markers on oxidative stress and muscle damage in soccer athletes after a match submitted to recovery strategies through CWI and PBMT

In elite soccer, players are frequently required to play consecutive matches interspersed by 3 days and complete physical performance recovery may not be achieved. Incomplete recovery might result in underperformance and injury. During congested schedules, recovery strategies are therefore required to alleviate post-match fatigue, regain performance faster and reduce the risk of injury. Recovery from exercise can be an important factor in performance during repeated bouts of exercise.

The strenuous exercise induces muscle cell structural damage, which results in increased plasma concentrations of muscle enzymes such as CK and LDH. The efflux of CK and LDH proteins from muscle may be attributed to increased permeability of the plasma membrane or intramuscular vasculature (or both). Thus, a reduction in these markers has been proposed as an indicator of recovery after strenuous exercise that induces muscle damage.

Inclusion Criteria:Voluntary athletes were soccer players aged 16 to 17 years, healthy, male, with no history of autoimmune diseases, who did not present previous muscular lesions in the period of 3 months prior to the study and who are participating of the category championships.

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Exclusion Criteria:

• No soccer playres.