title: Efficacy of two forms of electrical stimulation in increasing quadriceps strength: a randomized controlled trial.
abstract: OBJECTIVE
  To investigate whether electrical stimulation is effective in improving quadriceps strength in healthy subjects and to compare interferential and low-frequency current in terms of the effects on quadriceps strength and perceived discomfort.
  
  
  METHODS
  Randomized, controlled study.
  
  
  METHODS
  Physical Medicine and Rehabilitation Department in a university hospital.
  
  
  METHODS
  Thirty medical faculty students, divided into three groups, participated in the study.
  
  
  METHODS
  Group A received electrical stimulation with bipolar interferential current while group B received electrical stimulation with low-frequency current (symmetrical biphasic). Group C served as the control group. Electrical stimulation was given for 15 minutes, five days a week for three weeks, at a maximally tolerated intensity with the knee fully extended in the sitting position.
  
  
  METHODS
  Before and after the study, quadriceps strength was measured with a Cybex dynamometer isokinetically at the angular velocities of 60 degrees/s and 120 degrees/s. The perceived discomfort experienced with each type of electrical stimulation was quantified by the use of a visual analogue scale (VAS).
  
  
  RESULTS
  Statistically significant increase in isokinetic strength was observed after training in group A and group B. Increase in strength did not differ between the stimulation groups. No significant change in strength occurred in group C. Perceived discomfort by the stimulation groups was not significantly different.
  
  
  CONCLUSIONS
  Both interferential and low-frequency currents can be used in strength training with the parameters used in this study.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Dokuz Eylul University Medical Faculty, Izmir, Turkey. cigdem.bircan@deu.edu.tr
authors.forename: Cigdem
authors.initials: C
authors.lastname: Bircan
authors.forename: Ozlem
authors.initials: O
authors.lastname: Senocak
authors.forename: Ozlen
authors.initials: O
authors.lastname: Peker
authors.forename: Aylin
authors.initials: A
authors.lastname: Kaya
authors.forename: Sebnem Akgol
authors.initials: SA
authors.lastname: Tamci
authors.forename: Selmin
authors.initials: S
authors.lastname: Gulbahar
authors.forename: Elif
authors.initials: E
authors.lastname: Akalin
mesh_terms: D000328:Adult; D004599:Electric Stimulation Therapy / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D013997:Time Factors