Abstract
CrossFit is high-intensity interval training involving routines called 'workouts of the day' (WOD). The aim of the present study is to analyse biochemical parameters and physical performance after two modalities of CrossFit WODs, and to evaluate 48-hour recovery. Twelve trained CrossFit practitioners (age: 30.4 ± 5.37 years; VO(2)max: 47.8 ± 3.63 ml/min/kg; 1RM Power Clean: 93.2 ± 7.62 kg) participated in the study. A crossover design was applied, and participants completed two modalities of WODs on separate days: WOD1 (as many rounds as possible) and WOD2 (rounds for time). Blood lactate, ratings of perceived exertion and heart rate were measured to determine the intensity of training sessions. Biochemical parameters and physical performance were evaluated before, immediately after, 24 hours after and 48 hours after exercise. There were significant differences in intensity between WOD1 and WOD2 (lactate: 13.3±1.87 vs. 18.38±2.02 mmol/L, heart rate mean: 127.6±11.1 vs. 159.8±12.1 bpm), and blood glucose concentrations were significantly higher after WOD2 (135.4 ± 19.6 vs. 167.4±19.6 mg/dL). After exercise, WOD1 and WOD2 caused significant increases of hepatic transaminases, creatine phosphokinase and blood glucose, as well as a large decrease in the physical performance evaluated by the plank test. All these values returned to baseline by 48 hours after exercise. Both WODs caused metabolic and muscular stress, as well as a decrease in physical performance. All the levels recovered at 48 hours, so the stress caused by CrossFit WODs did not induce a pathological state.