The performance of Muaythai athletes is determined by physiological and anthropometric characteristics, however, we have found an area of​​ opportunity in the search for these data, therefore, the information on the parameters that fighters must present according to this sport are from great importance. To know the state of mind, gastrointestinal symptoms and sleep, as well as physiological characteristics of heart rate variability, blood, urine, body composition and physical performance of athletes of the Muaythai State Selection of Nuevo León, Mexico heading to a Championship. National. Descriptive study with 17 athletes (13 men and 4 women) of the state Muaythai team of the state of Nuevo León, Mexico (Age: 18.65±7.33 years, height: 168±4.21 cm, training per week 12.62±13.90 hours, competitions/year: 3.29±1.79). At baseline, they answered three online questionnaires about mood, gastrointestinal symptoms, and sleep. Subsequently, a measurement of heart rate variability, blood and urine collection was performed. Body composition was assessed by anthropometry and a countermovement jump test was performed. The urine presented a value of 1.028±0.015 sg, as well as a weight of 64.01±7.03 kg and 57.38±6.73 kg, fat% of 10.11±25.10% and 15.25±3.27%, muscle% of 55.87±5.88 and 38.86±3.03 and a value of 30±7.42 cm and 25.3±9.08 cm in jump height for men and women, respectively. The fighters are hypohydrated, as well as with a higher weight and fat mass, as well as a lower muscle mass and jump height compared to the various combat disciplines worldwide. Due to the above, it is necessary to establish specific parameters for Muaythai