a Department of Kinesiology, McMaster University, Hamilton, ON L8S 4K1, Canada.
b Discipline of Physiology & Health, Cardiff School of Sport, Cardiff Metropolitan University, Cardiff CF5 2YB, Wales, UK.
Appl Physiol Nutr Metab. 2019 Aug;44(8):820-826. doi: 10.1139/apnm-2018-0544. Epub 2019 Jan 8.
Previous longitudinal studies suggest that left ventricular (LV) structure is unaltered with resistance exercise training (RT) in young men. However, evidence from aerobic exercise training suggests that early changes in functional LV wall mechanics may occur prior to and independently of changes in LV size, although short-term changes in LV mechanics and structural remodelling in response to RT protocols have not been reported. Therefore, the purpose of this study was to examine the effects of RT on LV mechanics in healthy men performing 2 different time-under-tension protocols. Forty recreationally trained men (age: 23 ± 3 years) were randomized into 12 weeks of whole-body higher-repetition RT (20-25 repetitions/set to failure at ∼30%-50% 1 repetition maximum (1RM); = 13), lower-repetition RT (8-12 repetitions/set to failure at ∼75%-90% 1RM; = 13), or an active control period ( = 14). Speckle tracking echocardiography was performed at baseline and following the intervention period. Neither RT program altered standard measures of LV volumes (end-diastolic volume, end-systolic volume, or ejection fraction; > 0.05) or indices of LV mechanics (total LV twist, untwisting rate, twist-to-shortening ratio, untwisting-to-twist ratio, or longitudinal strain; > 0.05). This is the first longitudinal study to assess both LV size and mechanics after RT in healthy men, suggesting a maintenance of LV size and twist mechanics despite peripheral muscle adaptations to the training programs. These results provide no evidence for adverse LV structural or functional remodelling in response to RT in young men and support the positive role of RT in the maintenance of optimal cardiovascular function, even with strenuous RT.
先前的纵向研究表明，在年轻男性中，抵抗运动训练（RT）不会改变左心室（LV）结构。然而，来自有氧运动训练的证据表明，LV 壁功能的早期变化可能发生在 LV 大小变化之前且独立于 LV 大小变化，尽管尚未报道 RT 方案对 LV 力学和结构重塑的短期变化。因此，本研究的目的是研究 RT 对进行 2 种不同张力下 RT 的健康男性的 LV 力学的影响。40 名有规律运动的男性（年龄：23 ± 3 岁）被随机分为进行 12 周全身高重复 RT（20-25 次/组，在 ∼30%-50%1 重复最大力量（1RM）下失败； = 13）、低重复 RT（8-12 次/组，在 ∼75%-90%1RM 下失败； = 13）或主动对照组（ = 14）。在基线和干预期后进行斑点追踪超声心动图检查。两种 RT 方案均未改变 LV 容积（舒张末期容积、收缩末期容积或射血分数； > 0.05）或 LV 力学指标（总 LV 扭转、解旋速度、扭转缩短比、解旋扭转比或纵向应变； > 0.05）的标准测量值。这是第一项评估健康男性 RT 后 LV 大小和力学的纵向研究，表明尽管外周肌肉对训练方案产生适应性，但 LV 大小和扭转力学仍保持不变。这些结果表明，在年轻男性中，RT 不会引起 LV 结构或功能重塑的不良反应，并支持 RT 在维持最佳心血管功能方面的积极作用，即使是在剧烈的 RT 下也是如此。
