Gorgey Ashraf S, Shepherd Collin
Department of Physical Medicine and Rehabilitation, Hunter Holmes McGuire Medical Center, 1201 Broad Rock Boulevard, Richmond, VA 23249, USA.
J Spinal Cord Med. 2010;33(1):90-5. doi: 10.1080/10790268.2010.11689681.
Skeletal muscle atrophy is a common adaptation after spinal cord injury (SCI) that results in numerous health-related complications. Neuromuscular electrical stimulation (NMES) has been recognized as an effective tool, which attenuates atrophy and evokes hypertrophy.
To investigate the effects of NMES resistance training (RT) on individual muscle groups and adipose tissue of the right thigh after stimulation of the knee extensor muscle group in a man with chronic SCI.
A 22-year-old man with a complete SCI sustained in a motorcycle accident 5 years prior to participation in this study.
The participant underwent training twice a week for 12 weeks, including unilateral progressive RT of the right knee extensor muscle group using NMES and ankle weights. The stimulation was applied to knee extensors while the participant was sitting in his wheelchair. A series of T1-weighted magnetic resonance images were acquired for the whole right thigh prior to and after training. Skeletal muscle cross-sectional areas were measured of the whole thigh, knee extensors, hip adductors, hamstrings, and sartorius and gracilis muscle groups. Additionally, intramuscular fat and subcutaneous fat of the thigh were measured.
At the end of 12 weeks, the participant was able to lift 17 lbs during full knee extension. Average skeletal muscle cross-sectional areas increased in all of the measured muscle groups (12%-43%). Hypertrophy ranging from 30% to 112% was detected in multiaxial slices after the NMES RT protocol. Intramuscular fat decreased by more than 50% and subcutaneous fat increased by 24%.
Unilateral NMES RT protocol evoked hypertrophy in the knee extensor and adjacent skeletal muscle groups and was associated with a reduction in intramuscular fat in a person with a chronic SCI. Additionally, subcutaneous adipose tissue cross-sectional areas increased in response to RT.
骨骼肌萎缩是脊髓损伤(SCI)后常见的适应性变化,会导致诸多与健康相关的并发症。神经肌肉电刺激(NMES)已被公认为一种有效的工具,可减轻萎缩并引发肥大。
研究在一名慢性脊髓损伤男性中,对膝伸肌肌群进行刺激后,NMES抗阻训练(RT)对右大腿各肌肉群和脂肪组织的影响。
一名22岁男性,在参与本研究前5年因摩托车事故导致完全性脊髓损伤。
参与者每周接受两次训练,共12周,包括使用NMES和踝部负重对右膝伸肌肌群进行单侧渐进性抗阻训练。当参与者坐在轮椅上时,对膝伸肌施加刺激。在训练前后获取整个右大腿的一系列T1加权磁共振图像。测量整个大腿、膝伸肌、髋内收肌、腘绳肌以及缝匠肌和股薄肌肌群的骨骼肌横截面积。此外,还测量了大腿的肌内脂肪和皮下脂肪。
12周结束时,参与者在膝关节完全伸展时能够举起17磅的重量。所有测量的肌肉群的平均骨骼肌横截面积均增加(12% - 43%)。在NMES抗阻训练方案后,多轴切片中检测到肥大范围为30%至112%。肌内脂肪减少超过50%,皮下脂肪增加24%。
单侧NMES抗阻训练方案可使慢性脊髓损伤患者的膝伸肌及相邻骨骼肌群产生肥大,并与肌内脂肪减少相关。此外,皮下脂肪组织横截面积因抗阻训练而增加。