The effect of joint angle on the timing of muscle contractions elicited by neuromuscular electrical stimulation

  • Sinclair P
  • Smith R
  • Davis G
  • 2


    Mendeley users who have this article in their library.
  • N/A


    Citations of this article.


Neuromuscular electrical stimulation was used to evoke isometric knee extension contractions in seven individuals with spinal cord injury (SCI) and the time for knee extension torque to rise and fall was measured across a range of knee angles. The stimulated muscles took more than twice as long to develop 50% of maximum torque at an angle of 15 degrees, compared to an angle of 90 degrees. This time difference comprised both an increased delay before torque rose above resting levels (31 +/- 3 ms at 90 degrees, 67 +/- 24 ms at 15 degrees), and a prolonged duration over which torque was rising (72 +/- 14 ms at 90 degrees, 140 +/- 62 ms at 15 degrees). There was no change, however, in the time taken for torque to fall after cessation of stimulation at different knee angles (58 +/- 5-ms delay, 60 +/- 11-ms fall time). The difference in torque rise time with joint angle has implications for modeling functional activities that differ greatly in their joint angles. This study provides regression equations whereby activation times for the quadriceps muscles of individuals with SCI can be predicted for specific angles of knee flexion

Author-supplied keywords

  • Activation
  • Australia
  • Change
  • Electrical stimulation
  • Exercise
  • Injury
  • Isometric
  • Knee
  • Muscle
  • Muscle Contraction
  • Muscles
  • Neuromuscular
  • Quadriceps
  • Quadriceps Muscle
  • Spinal
  • Spinal Cord
  • Spinal Cord Injuries
  • Spinal cord injury
  • Stimulation
  • Torque
  • injuries
  • joint

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • P J Sinclair

  • R M Smith

  • G M Davis

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free