CrossFit is a modality that is characterized by high-intensity intervals, providing practitioners with the development of skills that promote improved sports performance. Similarly, ischemic preconditioning (ICP) is a form of training that aims to optimize muscle performance by increasing tissue tolerance to episodes of ischemia followed by reperfusion.

To compare the acute effects of different PCI protocols on muscle performance and superficial thermal response in amateur CrossFit athletes.

This is a crossover study. The participants were 15 subjects (10 men and 5 women) of both genders, aged between 18 and 35 years, with no history of metabolic, cardiovascular, or locomotor system diseases with an Ankle Brachial Index (ABI) between 0.91 and 1.30 and who responded negatively to all items of the Physical Activity Readiness Questionnaire/PAR-Q. After selection, they randomly performed one of the following three protocols: 1) ischemic preconditioning with 2 limb ischemia cycles (PCI-2C); 2) ischemic preconditioning with 4 cycles of limb ischemia (PCI-4C); 3) control ischemic preconditioning (PCI-CONT). Isometric strength measurements of elbow and knee extensors were performed before and after (WOD) and infrared thermography, at baseline, after PCI and WOD. Data were analyzed using SPSS software (v. 20.0), adopting a P≤0,05. ANOVA (one way) was used to analyze the time of execution of the WOD and to analyze the isometric strength of the elbow and knee extensors, in addition to repeated measures ANOVA to compare the averages, normalized, of the temperatures throughout the moments of evaluation.

No significant differences were found between the protocols regarding the WOD execution time (F:2;12=0.09; P=0.916), as well as for the isometric strength of elbow extensors (F:2; 12=0.248; P=0.781) and knee (F:2;12=0.827; P=0.439). For the upper, lower and facial ROI thermograms, no significant differences were observed between the protocols (P>0.05); however, there were significant differences between assessments (P<0.05).

The protocols behaved similarly in terms of execution time and isometric strength of elbow and knee extensors. However, the normalized temperature means decreased over the course of the evaluations.

Contribute to an improvement in neuromuscular performance in CrossFit practitioners, in addition to showing a greater understanding of the surface temperature of the skin after application of ischemic preconditioning and training.