title: Metabolic and cardiovascular responses during voluntary pedaling exercise with electrical muscle stimulation.
abstract: OBJECTIVE
  We aimed to test the effect of additional electrical muscle stimulation (EMS) during moderate-intensity voluntary pedaling exercise on metabolic and cardiovascular responses.
  
  
  METHODS
  Eleven healthy male subjects performed moderate-intensity pedaling exercise at a constant workload (80% of ventilatory threshold) for 20 min while EMS was applied to thigh muscles from 5 to 10 min and from 15 to 20 min during the exercise.
  
  
  RESULTS
  A significantly higher oxygen uptake (VO₂), heart rate, and respiratory gas exchange ratio were observed during the exercise periods with EMS despite the constant workload. These changes were accompanied by an elevated blood lactate concentration, suggesting the existence of additional fast-twitch motor unit (MU) recruitment during the exercise with EMS.
  
  
  CONCLUSIONS
  Our data suggest that the use of intermittent EMS during a constant load exercise mimics the high-intensity interval training, possibly due to additional fast-twitch MU recruitment and co-contractions of the quadriceps and hamstrings muscles, leading to higher anaerobic metabolism and a lower mechanical efficiency.
authors.affiliation: School of International Liberal Studies, Chukyo University, Nagoya, Japan, wkohei@lets.chukyo-u.ac.jp.
authors.forename: Kohei
authors.initials: K
authors.lastname: Watanabe
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Taniguchi
authors.forename: Toshio
authors.initials: T
authors.lastname: Moritani
mesh_terms: D000328:Adult; D004558:Electric Stimulation; D015444:Exercise; D005080:Exercise Test; D006339:Heart Rate; D006801:Humans; D008297:Male; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000378:metabolism / Q000502:physiology*; D010101:Oxygen Consumption; D011659:Pulmonary Gas Exchange