Effect of Stochastic Modulation of Inter-Pulse Interval During Stimulated Isokinetic Leg Extension

Recumbent cycling exercise achieved by functional electrical stimulation (FES) of the paralyzed leg muscles is effective for cardiopulmonary and musculoskeletal conditioning after spinal cord injury, but its full potential has not yet been realized. Mechanical power output and efficiency is very low and endurance is limited due to early onset of muscle fatigue. The aim of this work was to compare stochastic modulation of the inter-pulse interval (IPI) to constant-frequency stimulation during an isokinetic leg extension task similar to FES-cycling. Seven able-bodied subjects participated: both quadriceps muscles were stimulated (n = 14) with two activation patterns (P1-constant frequency, P2-stochastic IPI). There was significantly higher power output with P2 during the first 30 s (p = 0.0092), the last 30 s (p = 0.018) and overall (p = 0.0057), but there was no overall effect on fatiguability when stimulation frequency was randomly modulated.

[1]  Marco A Minetto,et al.  Muscle motor point identification is essential for optimizing neuromuscular electrical stimulation use , 2014, Journal of NeuroEngineering and Rehabilitation.

[2]  K. J. Hunt,et al.  Energetics of paraplegic cycling: a new theoretical framework and efficiency characterisation for untrained subjects , 2007, European Journal of Applied Physiology.

[3]  Christine K. Thomas,et al.  Fatigue of paralyzed and control thenar muscles induced by variable or constant frequency stimulation. , 2003, Journal of neurophysiology.

[4]  K. Hunt,et al.  Long‐term intensive electrically stimulated cycling by spinal cord–injured people: Effect on muscle properties and their relation to power output , 2008, Muscle & nerve.

[5]  Jose L Pons,et al.  A comparison of customized strategies to manage muscle fatigue in isometric artificially elicited muscle contractions for incomplete SCI subjects , 2013 .

[6]  M. H. Laughlin,et al.  Skeletal muscle blood flow capacity: role of muscle pump in exercise hyperemia. , 1987, The American journal of physiology.

[7]  R. Johansson,et al.  Reflex origin for the slowing of motoneurone firing rates in fatigue of human voluntary contractions. , 1986, The Journal of physiology.

[8]  C D Marsden,et al.  "Muscular wisdom" that minimizes fatigue during prolonged effort in man: peak rates of motoneuron discharge and slowing of discharge during fatigue. , 1983, Advances in neurology.

[9]  Stuart A. Binder‐Macleod,et al.  Switching stimulation patterns improves performance of paralyzed human quadriceps muscle , 2005, Muscle & nerve.

[10]  Kenneth J Hunt,et al.  Effect of detraining on bone and muscle tissue in subjects with chronic spinal cord injury after a period of electrically-stimulated cycling: a small cohort study. , 2009, Journal of rehabilitation medicine.

[11]  Kenneth J Hunt,et al.  High-volume FES-cycling partially reverses bone loss in people with chronic spinal cord injury. , 2008, Bone.

[12]  Kenneth J Hunt,et al.  Cardiorespiratory and power adaptations to stimulated cycle training in paraplegia. , 2008, Medicine and science in sports and exercise.

[13]  Chris M Gregory,et al.  Recruitment patterns in human skeletal muscle during electrical stimulation. , 2005, Physical therapy.

[14]  B. Bigland-ritchie,et al.  Muscle fatigue induced by stimulation with and without doublets , 2000, Muscle & nerve.

[15]  M. Popovic,et al.  Reducing muscle fatigue due to functional electrical stimulation using random modulation of stimulation parameters. , 2005, Artificial organs.

[16]  Jesse C. Dean,et al.  Motor unit recruitment during neuromuscular electrical stimulation: a critical appraisal , 2011, European Journal of Applied Physiology.

[17]  D. Graupe,et al.  Stochastically-modulated stimulation to slow down muscle fatigue at stimulated sites in paraplegics using functional electrical stimulation for leg extension , 2000, Neurological research.

[18]  K J Hunt,et al.  Energetics of paraplegic cycling: adaptations to 12 months of high volume training. , 2012, Technology and health care : official journal of the European Society for Engineering and Medicine.

[19]  S A Binder-Macleod,et al.  Effects of activation pattern on human skeletal muscle fatigue , 1998, Muscle & nerve.

[20]  Anthony S Wexler,et al.  Effects of activation pattern on nonisometric human skeletal muscle performance. , 2007, Journal of applied physiology.

[21]  Stuart A Binder-Macleod,et al.  Using Customized Rate-Coding and Recruitment Strategies to Maintain Forces During Repetitive Activation of Human Muscles , 2008, Physical Therapy.

[22]  M. Popovic,et al.  The effect of random modulation of functional electrical stimulation parameters on muscle fatigue , 2006, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[23]  K. Hunt,et al.  Metabolic efficiency of volitional and electrically stimulated cycling in able-bodied subjects. , 2013, Medical engineering & physics.

[24]  Samuel C. K. Lee,et al.  Effect of electrical stimulation pattern on the force responses of paralyzed human quadriceps muscles , 2007, Muscle & nerve.

[25]  Stuart A Binder-Macleod,et al.  Effects of stimulation frequencies and patterns on performance of repetitive, nonisometric tasks. , 2002, Journal of applied physiology.

[26]  K J Hunt,et al.  On the efficiency of FES cycling: a framework and systematic review. , 2012, Technology and health care : official journal of the European Society for Engineering and Medicine.

[27]  Stuart A Binder-Macleod,et al.  Strategies that improve paralyzed human quadriceps femoris muscle performance during repetitive, nonisometric contractions. , 2005, Archives of physical medicine and rehabilitation.