You are here

Whole Body Oxygen Uptake and Evoked Torque During Subtetanic Isometric Electrical Stimulation of the Quadriceps Muscles in a Single 30-Minute Session


Brian Caulfield, Conor M. Minogue, Madeleine Lowery

Publication Type: 
Refereed Original Article
Objective: To evaluate the time course of fatigue in torque output and oxygen uptake during isometric subtetanic neuromuscular electrical stimulation (NMES) to facilitate the design of NMES-based rehabilitation protocols that can accumulate a defined aerobic exercise volume within a given time period. Design: Single-arm intervention study with within-subject comparisons. Setting: University research laboratory. Participants: Volunteer sample of healthy men (NZ11; mean age, 34.211.5y; range, 19e53y; body mass, 79.111.7kg; range, 58e100kg). Intervention: A single 30-minute session of continuous bilateral isometric quadriceps NMES at 4Hz evoking a mean twitch amplitude of 12% of the maximum voluntary contraction. Main Outcome Measures: Whole body oxygen consumption rate (V_ O2), and evoked torque were measured simultaneously throughout. Results: Mean increment in V_ O2 was 596238mL/min, and average exercise intensity during the session was 3.47 metabolic equivalents. The V_ O2 and torque declined slowly at a rate of .54%.31% and .47%.57% per minute, respectively. Conclusions: Despite having a higher incremental V_ O2, the observed fatigue rate was considerably less than that previously reported during intermittent isometric tetanic stimulation, suggesting that subtetanic isometric NMES is more sustainable for exercise interventions aimed at accumulating a therapeutic aerobic exercise volume. Archives of Physical Medicine and Rehabilitation 2014;-:------- ยช 2014 by the American Congress of Rehabilitation Medicine
Digital Object Identifer (DOI): 
Publication Status: 
Publication Date: 
Arch Phys Med Rehabil
Research Group: 
National University of Ireland, Dublin (UCD)
Open access repository: 
Publication document: