Health and Human Performance Laboratory, Department of Health and Human Sciences, Loyola Marymount University, Life Sciences Building 181, 1 LMU Drive, MS 8888, Los Angeles, CA, 90045, USA.
Department of Psychology, Loyola Marymount University, Los Angeles, CA, USA.
BMC Musculoskelet Disord. 2020 Nov 10;21(1):729. doi: 10.1186/s12891-020-03753-w.
Intensity of resistance training history might be omitted or poorly ascertained in prescreening or data questionnaires involving musculoskeletal health. Failure to identify history of high-versus low-intensity training may overlook higher effect sizes with higher intensities and therefore diminish the precision of statistical analysis with resistance training as a covariate and bias the confirmation of baseline homogeneity for experimental group designation. The purpose was to determine the degree to which a single question assessing participant history of resistance training intensity predicted differences in musculoskeletal health.
In the first research aim, participants were separated into groups with a history (RT) and no history (NRT) of resistance training. The second research aim evaluated the history of resistance training intensity on muscular strength, lean mass, and bone mineral density (BMD), RT participants were reassigned into a low- (LIRT) or high-intensity resistance training group (HIRT). 83 males and 87 females (19.3 ± 0.6 yrs., 171.1 ± 9.9 cm, 67.1 ± 10.5 kg, 22.9 ± 2.8 BMI, 26.2 ± 7.2% body fat) completed handgrip dynamometry (HG) and dual-energy x-ray absorptiometry scans (DXA) for BMD and bone mineral-free lean mass (BFLM).
A 3-group method (NRT, LIRT, HIRT) reduced type-I error compared with the 2-group method (NRT, RT) in characterizing the likely effects of one's history of resistance training. For the second aim, HIRT had significantly (p < 0.05) greater HG strength (76.2 ± 2.2 kg) and arm BFLM (6.10 ± 0.16 kg) than NRT (67.5 ± 1.3 kg; 4.96 ± 0.09 kg) and LIRT (69.7 ± 2.0 kg; 5.42 ± 0.14 kg) while also showing significantly lower muscle quality (HG/BFLM) than NRT (13.9 ± 0.2 vs. 12.9 ± 0.3). HIRT had greater BMD at all sites compared to NRT (whole body = 1.068 ± 0.008 vs. 1.120 ± 0.014; AP spine = 1.013 ± 0.011 vs. 1.059 ± 0.019; lateral spine = 0.785 ± 0.009 vs. 0.846 ± 0.016; femoral neck = 0.915 ± 0.013 vs. 0.970 ± 0.022; total hip = 1.016 ± 0.012 vs. 1.068 ± 0.021 g/cm) while LIRT revealed no significant skeletal differences to NRT.
Retrospective identification of high-intensity history of resistance training appears critical in characterizing musculoskeletal health and can be ascertained easily in as little as a single, standalone question. Both retrospective-questionnaire style investigations and pre-screening for potential participation in prospective research studies should include participant history of resistance training intensity.
在涉及肌肉骨骼健康的预筛选或数据问卷中，可能会遗漏或未能准确确定抗阻训练的强度。未能识别高与低强度训练的历史可能会忽略高强度训练的更高效果大小，从而降低抗阻训练作为协变量进行统计分析的精度，并对实验组指定的基线同质性的确认产生偏差。目的是确定评估参与者抗阻训练强度史的单一问题在多大程度上预测肌肉骨骼健康的差异。
在第一个研究目标中，参与者分为有（RT）和无（NRT）抗阻训练史的组。第二个研究目标评估了抗阻训练强度史对肌肉力量、瘦体重和骨密度（BMD）的影响，将 RT 参与者重新分配到低强度（LIRT）或高强度抗阻训练组（HIRT）。83 名男性和 87 名女性（19.3±0.6 岁，171.1±9.9 厘米，67.1±10.5 千克，22.9±2.8 BMI，26.2±7.2%体脂）完成了握力测力计（HG）和双能 X 射线吸收法（DXA）扫描，用于 BMD 和无骨脂肪的瘦体重（BFLM）。
与 2 组方法（NRT、RT）相比，3 组方法（NRT、LIRT、HIRT）在描述一个人抗阻训练史的可能影响方面降低了 I 型错误。对于第二个目标，HIRT 的 HG 强度（76.2±2.2 千克）和手臂 BFLM（6.10±0.16 千克）显著高于 NRT（67.5±1.3 千克；4.96±0.09 千克）和 LIRT（69.7±2.0 千克；5.42±0.14 千克），同时肌肉质量（HG/BFLM）也显著低于 NRT（13.9±0.2 比 12.9±0.3）。HIRT 在所有部位的 BMD 均高于 NRT（全身=1.068±0.008 比 1.120±0.014；AP 脊柱=1.013±0.011 比 1.059±0.019；侧位脊柱=0.785±0.009 比 0.846±0.016；股骨颈=0.915±0.013 比 0.970±0.022；全髋=1.016±0.012 比 1.068±0.021 g/cm），而 LIRT 与 NRT 相比没有显著的骨骼差异。
回顾性确定高强度抗阻训练史对于描述肌肉骨骼健康至关重要，只需一个简单的独立问题就可以轻松确定。回顾性问卷调查式研究和前瞻性研究潜在参与者的预筛选都应包括参与者的抗阻训练强度史。
