Haddock Christopher K, Poston Walker S C, Heinrich Katie M, Jahnke Sara A, Jitnarin Nattinee
National Development and Research Institutes, Inc., Institute for Biobehavioral Health Research, 1920 West 143rd Street, Suite 120, Leawood, KS 66224.
Department of Kinesiology, College of Human Ecology, 920 Denison Avenue, 1A Natatorium, Kansas State University, Manhattan, KS 66506.
Mil Med. 2016 Nov;181(11):e1508-e1514. doi: 10.7205/MILMED-D-15-00503.
High intensity functional training (HIFT) programs are designed to address multiple fitness domains, potentially providing improved physical and mental readiness in a changing operational environment. Programs consistent with HIFT principals such as CrossFit, SEALFIT and the US Marine Corps' High Intensity Tactical Training (HITT) are increasingly popular among military personnel. The goal of HIFT programs is to produce high levels of cardiorespiratory fitness, endurance and strength that exceed those achieved by following current physical activity recommendations.
Given the investment in and popularity of HIFT in the military, it is important to consider the potential impact of this approach to fitness training for the health of military personnel and their risk of training injury. In a previous report in this journal, we addressed the question of whether HIFT was associated with higher injury rates compared to other exercise programs. We argued that concerns about the injury potential of HIFT exercise programs were not supported by the scientific literature to date, although additional research was needed to directly compare injury rates in approaches such as CrossFit to traditional military fitness programs. In this article we will review the scientific data on the practical, health and fitness benefits of HIFT exercise programs for military populations.
Practical benefits to HIFT exercise programs include shorter training times and volumes, exercises which simulate combat tasks, lower equipment costs, reduced potential for boredom and adaptation as a result of constant variation, less injury potential compared to high volume endurance training, and scalability to all fitness levels and rehabilitation needs. For instance, HIFT training volumes are typically between 25% to nearly 80% less than traditional military fitness programs without reductions in fitness outcomes. HIFT program also provide an impressive range of health benefits such as the promotion of metabolic conditioning and muscular strength, less systemic inflammation or oxidative damage compared to sustained aerobic activity, and promoting general physical preparedness (GPP) for the unpredictable physical demands of combat.
Given the unique benefits of HIFT, we recommend that these programs become the standard for military physical training. Despite the promise of HIFT fitness programs, questions remain about implementing these programs in the military context. For instance, no large scale randomized trials comparing traditional military physical training with HIFT programs on both health and injury outcomes have been conducted. Such a trial could identify key elements from both types of programs which should be incorporated in future approaches to military fitness training. Also, research regarding the optimal ways of implementing HIFT to maximize both GPP and combat oriented physical skills is lacking. It is likely that an approach to HIFT training which promotes GPP for all personnel along with specialized elements selected on the basis of individual occupation demands would be maximally disseminable in the military.
高强度功能训练（HIFT）计划旨在涵盖多个健身领域，有可能在不断变化的作战环境中提高身体和心理准备状态。与HIFT原则相符的计划，如CrossFit、海豹突击队体能训练（SEALFIT）以及美国海军陆战队的高强度战术训练（HITT），在军事人员中越来越受欢迎。HIFT计划的目标是产生高水平的心肺适能、耐力和力量，超过遵循当前体育活动建议所达到的水平。
鉴于HIFT在军事领域的投入和受欢迎程度，重要的是要考虑这种健身训练方法对军事人员健康及其训练受伤风险的潜在影响。在本杂志之前的一篇报告中，我们探讨了与其他运动计划相比，HIFT是否与更高的受伤率相关。我们认为，尽管需要更多研究来直接比较CrossFit等方法与传统军事健身计划的受伤率，但迄今为止科学文献并不支持对HIFT运动计划受伤可能性的担忧。在本文中，我们将回顾关于HIFT运动计划对军事人群的实际、健康和健身益处的科学数据。
HIFT运动计划的实际益处包括训练时间和量更短、模拟战斗任务的练习、设备成本更低、因不断变化而减少无聊感和适应性、与大量耐力训练相比受伤可能性更小，以及可扩展至所有健身水平和康复需求。例如，HIFT训练量通常比传统军事健身计划少25%至近80%，而健身效果却没有降低。HIFT计划还提供了一系列令人印象深刻的健康益处，如促进代谢调节和肌肉力量、与持续有氧运动相比全身炎症或氧化损伤更少，以及促进对战斗中不可预测的身体需求的总体身体准备（GPP）。
鉴于HIFT的独特益处，我们建议这些计划成为军事体能训练的标准。尽管HIFT健身计划前景广阔，但在军事背景下实施这些计划仍存在问题。例如，尚未进行大规模随机试验来比较传统军事体能训练与HIFT计划对健康和受伤结果的影响。这样的试验可以确定两种计划中的关键要素，这些要素应纳入未来的军事健身训练方法中。此外，缺乏关于实施HIFT以最大限度提高GPP和以战斗为导向的身体技能的最佳方法的研究。一种促进所有人员GPP并根据个人职业需求选择专门要素相结合的HIFT训练方法，在军事中可能最易于推广。
