Physiological responses in HIFT/CrossFit®: oxygen consumption, energy expenditure, and METs for health and fitness
Keywords:
physical exercise; physical education and training; fitness centers; metabolismAbstract
High-Intensity Functional Training (HIFT), popularly represented by CrossFit®, has gained importance over time as an effective strategy for improving physical fitness and promoting health. This type of training builds strength and endurance through varied functional movements performed at high intensity and with minimal breaks. HIFT sessions have been observed to produce significant acute physiological responses, including oxygen consumption (VO2), heart rate, and energy expenditure; these results are better or superior in many cases to the traditional exercise. Recent research shows that the structure of the session, especially its duration, directly impact cardiorespiratory and metabolic responses. Consequently, longer protocols, such as the “Cindy” WOD, have presented better and greater physiological demands compared to shorter ones. Furthermore, CrossFit® has been shown to generate higher peak oxygen consumption, total energy expenditure, and maximum heart rate compared to conventional methods. However, its efficiency has been highlighted because it produces significant effects in less time, making it an important option and opportunity for people with time constraints. Its application is useful for both active and inactive populations, as long as it adapts to the needs and conditions of each individual. In conclusion, HIFT/CrossFit® has become an important, viable, reliable, and effective exercise modality for health and fitness programs.
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