Muthalib, Makii, Graham Kerr, Kazunori Nosaka, and Stephane Perrey. “Local Muscle Metabolic Demand Induced by Neuromuscular Electrical Stimulation and Voluntary Contractions at Different Force Levels: A NIRS Study”. European Journal of Translational Myology 26, no. 2 (June 13, 2016). Accessed May 24, 2019. https://www.pagepressjournals.org/index.php/bam/article/view/6058.