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Are extreme conditioning programmes effective and safe? A narrative review of high-intensity functional training methods research paradigms and findings
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    The current evidence no longer supports the term “extreme conditioning programes;” let’s call it high-intensity functional training instead.
    • Yuri Feito, Associate Professor Kennesaw State University (USA)
    • Other Contributors:
      • Nathan Jenkins, Associate Professor
      • Derek Crawford, Assistant Professor
      • Gerald T. Mangine, Assistant Professor

    Dear Editor in Chief:

    We read with great interest the recently published article by Tibana and de Sousa (1) titled “Are extreme conditioning programmes effective and safe? A narrative review of high intensity functional training methods research paradigms and findings.” We appreciate the opportunity to write this letter and hope to clarify some of the authors’ conclusions. Although the authors provide several examples of what they refer to as “extreme conditioning programs” we will focus mainly on the statements and evidence related to High Intensity Functional Training (HIFT), more commonly known as CrossFitTM training, as the authors’ review focuses primarily on this particular training program. We feel the authors have taken a biased position in describing this type of training and that their position is based on inaccurate and highly speculative interpretations of a fraction of the existing literature.

    Research examining the acute and long-term responses to HIFT, as well as the incidence of injury, is quite limited. The observed responses predominantly describe changes from baseline and in the case of long-term adaptations, generally show a positive outcome. Further, the few studies that make comparisons to other exercise forms only show select differences. More importantly, by the authors’ own admission, research examining the risk of injury do not suggest HIFT/CrossFitTM to be different from other forms of recreational exercise. Yet, the authors descri...

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    Conflict of Interest:
    None declared.