Carr Joshua C, Voskuil Caleb C, Andrushko Justin W, MacLennan Rob J, DeFreitas Jason M, Stock Matt S, Farthing Jonathan P
Department of Kinesiology, Kansas State University, Manhattan, Kansas, USA.
Department of Kinesiology, Texas Christian University, Fort Worth, Texas, USA.
Physiol Rep. 2025 Apr;13(8):e70329. doi: 10.14814/phy2.70329.
This pilot study consists of a two-phase intervention to examine the effectiveness of unilateral resistance training to mitigate the negative consequences of immobilization and expedite the restoration of muscle strength and size following a period of retraining. Ten females were randomized to a unilateral training (TRAIN, n = 6) or control (CON, n = 4) group. During Phase 1, all participants wore an arm sling for a total of 4 weeks on their non-dominant arm. This phase required the TRAIN group to perform unilateral resistance training with the non-immobilized arm while the CON group did not. Phase 2 commenced thereafter and consisted of 4 weeks of bilateral resistance training for both groups. Outcome measures of neuromuscular function and muscle size were assessed at baseline and after each phase, with neuromuscular function quantified by maximal dynamic and isometric strength alongside electromyographic responses and muscle size measured using ultrasonography and regional lean mass via DEXA. Unilateral training of the non-immobilized arm during Phase 1 attenuated dynamic (p < 0.05; g > 1.2), but not isometric (p > 0.40; g < 0.095), strength loss following immobilization and showed large effects for improving the recovery of strength after retraining. Similarly, the imaging data show the relative changes in muscle size and regional lean mass of the non-dominant arm favor TRAIN. Although the small sample prevents definitive conclusions, our study suggests resistance training of the non-immobilized arm attenuates muscle weakness and atrophy for the contralateral, immobilized arm during immobilization and facilitates their recovery following retraining.
这项初步研究包括一个两阶段干预措施，以检验单侧阻力训练在减轻制动负面影响以及在一段时间的再训练后加速肌肉力量和尺寸恢复方面的有效性。十名女性被随机分为单侧训练组（TRAIN，n = 6）或对照组（CON，n = 4）。在第一阶段，所有参与者在其非优势手臂上佩戴手臂吊带，总共4周。此阶段要求TRAIN组用未制动的手臂进行单侧阻力训练，而CON组不进行。此后开始第二阶段，两组均进行为期4周的双侧阻力训练。在基线和每个阶段后评估神经肌肉功能和肌肉尺寸的结果指标，神经肌肉功能通过最大动态和等长力量以及肌电图反应进行量化，肌肉尺寸使用超声检查测量，通过双能X线吸收法测量区域瘦体重。在第一阶段对未制动手臂进行单侧训练可减轻制动后动态力量的损失（p < 0.05；g > 1.2），但对等长力量无影响（p > 0.40；g < 0.095），并且对再训练后力量的恢复有显著效果。同样，成像数据显示非优势手臂的肌肉尺寸和区域瘦体重的相对变化有利于TRAIN组。尽管样本量小无法得出确定性结论，但我们的研究表明，对未制动手臂进行阻力训练可在制动期间减轻对侧制动手臂的肌肉无力和萎缩，并在再训练后促进其恢复。
