Potter Adam W, Friedl Karl E
United States Army Research Institute of Environmental Medicine (USARIEM), Natick, MA 01760, USA.
Mil Med. 2025 Jun 30;190(7-8):e1587-e1594. doi: 10.1093/milmed/usae554.
Military body fat standards were implemented in the 1980s to prevent obesity and associated poor military readiness. In the past 2 decades, enforcement of existing Army body composition standards has been eroded by the steady increase in national obesity rates, the demand for new recruits especially during the 2007 surge in Iraq, and the COVID epidemic in 2020. The diminishing qualified recruit pool puts a new focus on accession standards. The purpose of accession standards is to ensure that recruits will meet soldier standards, but accession standards have been relaxed to improve recruitment with an assumption that most recruits will achieve the retention standards during initial entry training. A new method of percent body fat estimation (%BF) adopted by the Army in 2024 further liberalizes both accession and retention standards. This study examined the impact of current accession and retention %BF standards on the proportion of the US population that would be disqualified from Army service.
This analysis was based on National Health and Nutrition Examination Survey (NHANES) statistical sampling of the US population, where height, weight, abdominal circumferences, and dual-energy x-ray absorptiometry (DXA) %BF data were available (n = 26,090, including 13,302 men and 12,788 women). The proportion of individuals in the NHANES data failing to meet weight screen and %BF standards based on age and sex categories were calculated using DXA and the new Army anthropometric method. A recent large dataset from another service was used to compare the new method to DXA.
Near one-third to one-half of American men and women failed to meet the current Army body composition standard (29, 39, 48, and 50% of men and 39, 45, 46, and 50% of women for age groups 17-20, 21-27, 28-29, and 40-59). More men than women benefited from more liberal accession standards to enter the Army above the retention standard to which they will be held after initial entry training (an additional 12, 11, 15, and 15% of men and 7, 1, 2, and 1% of women who met accession standards exceeded retention standards and would be expected to lose %BF after entry). Approximately one-fourth of women exceeded %BF but were under the height-weight screen; <10% of men were in this category. No men but 16% of the youngest women had low lean mass (<35 kg).
Army body composition standards are generous, extending to the limits of increased metabolic health risks and providing underestimates of actual %BF based on the behavior of circumference-based methods of body fat estimation. However, current standards do not accurately select or track physical readiness, especially for women, and should be updated. Modernization of physical readiness standards to meet the needs of the Army of 2030 could include adoption of new technologies that directly assess central adiposity, adequate muscle mass, and replace fitness testing with cardiac output metrics. With half of US adults projected to be obese by 2030, it is time for a review of the strategic goals of modernized military readiness standards.
20世纪80年代实施了军事体脂标准,以预防肥胖及由此导致的军事准备不足。在过去20年里,由于全国肥胖率稳步上升、对新兵的需求增加(尤其是在2007年伊拉克增兵期间)以及2020年的新冠疫情,陆军现有身体成分标准的执行受到了侵蚀。合格新兵库的减少使人们重新关注入伍标准。入伍标准的目的是确保新兵能够达到士兵标准,但为了提高征兵率,入伍标准已经放宽,前提是大多数新兵将在初始入伍训练期间达到留用标准。陆军于2024年采用的一种新的体脂百分比估计方法(%BF)进一步放宽了入伍和留用标准。本研究考察了当前入伍和留用%BF标准对不符合陆军服役条件的美国人口比例的影响。
本分析基于美国国家健康与营养检查调查(NHANES)对美国人口的统计抽样,该调查提供了身高、体重、腹围和双能X线吸收法(DXA)%BF数据(n = 26,090,包括13,302名男性和12,788名女性)。使用DXA和新的陆军人体测量方法,计算了NHANES数据中未达到基于年龄和性别的体重筛查和%BF标准的个体比例。使用另一个军种最近的一个大型数据集将新方法与DXA进行比较。
近三分之一到一半的美国男性和女性未达到当前陆军身体成分标准(17 - 20岁、21 - 27岁、28 - 29岁和40 - 59岁年龄组中,男性分别为29%、39%、48%和50%,女性分别为39%、45%、46%和50%)。受益于更宽松的入伍标准从而高于初始入伍训练后将被要求达到的留用标准进入陆军的男性多于女性(达到入伍标准且超过留用标准并预计入伍后体脂百分比会下降的男性额外增加了12%、11%、15%和15%,女性分别为7%、1%、2%和1%)。约四分之一的女性体脂百分比超标但身高体重筛查合格;不到10%的男性属于这一类别。没有男性但16%最年轻的女性瘦体重较低(<35千克)。
陆军身体成分标准较为宽松,已延伸至代谢健康风险增加的极限,并基于基于周长的体脂估计方法的特性低估了实际体脂百分比。然而,当前标准无法准确选拔或跟踪身体准备情况,尤其是对女性而言,应予以更新。为满足2030年陆军需求而对身体准备标准进行现代化改革,可包括采用直接评估中心性肥胖、足够肌肉量的新技术,并用心输出量指标取代体能测试。预计到2030年美国成年人中有一半将肥胖,现在是时候审视现代化军事准备标准的战略目标了。