Fornusek Ché, Davis Glen M
Rehabilitation Research Centre, Faculty of Health Sciences, University of Sydney, Sydney, NSW, Australia.
J Rehabil Med. 2004 Sep;36(5):232-7. doi: 10.1080/16501970410029843.
This study investigated the effect of pedal cadence upon torque production, power output and muscle fatigue rates during functional electrical stimulation evoked cycling in spinal cord injured individuals.
All subjects had complete thoracic spinal cord injuries T4-T9 (ASIA A) and had been functional electrical stimulation training regularly for at least 6 months.
One trial (n = 8) examined a low vs high pedal rate (20 and 50 rev x min(-1)) upon isolated muscle fatigue over 5 minutes. A second trial (n = 9) investigated the effect of cadence (15 vs 50 rev x min(-1)) upon performance during 35-minutes of functional electrical stimulation evoked cycling.
Peak torque produced by left quadriceps decayed significantly faster at the higher pedal cadence, indicating a higher rate of muscle fatigue. Functional electrical stimulation cycling over 35 minutes also revealed that peak and average torques were significantly greater at the lower cadence. From 15 minutes onwards, power output was significantly higher at 50 rev x min(-1) FES-cycling, compared with 15 rev x min(-1).
The higher muscle forces observed during low cadence functional electrical stimulation cycling should offer improvements over traditional pedalling velocities for training leg strength in individuals with spinal cord injury.
本研究调查了脊髓损伤个体在功能性电刺激诱发的骑行过程中，踏频对扭矩产生、功率输出和肌肉疲劳率的影响。
所有受试者均为T4 - T9节段的完全性胸段脊髓损伤（美国脊髓损伤协会A级），且已定期进行功能性电刺激训练至少6个月。
一项试验（n = 8）研究了低踏频与高踏频（20和50转×分钟⁻¹）对5分钟内孤立肌肉疲劳的影响。另一项试验（n = 9）调查了踏频（15与50转×分钟⁻¹）对35分钟功能性电刺激诱发骑行期间运动表现的影响。
在较高踏频时，左股四头肌产生的峰值扭矩衰减明显更快，表明肌肉疲劳率更高。35分钟的功能性电刺激骑行还显示，较低踏频时的峰值扭矩和平均扭矩明显更大。从15分钟起，与15转×分钟⁻¹相比，50转×分钟⁻¹的功能性电刺激骑行的功率输出明显更高。
在脊髓损伤个体中，低踏频功能性电刺激骑行期间观察到的较高肌肉力量，相较于传统蹬踏速度，应能在训练腿部力量方面带来改善。
