Abstract
Introduction: Afferent information from exercising muscle contributes to the sensation of exercise-induced muscle pain. Transcutaneous electrical nerve stimulation (TENS) delivers low–voltage electrical currents to the skin, inhibiting nociceptive afferent information. The use of TENS in reducing perceptions of exercise-induced pain has not yet been fully explored. This study aimed to investigate the effect of TENS on exercise-induced muscle pain, pacing strategy, and performance during a 5-km cycling time trial (TT).Methods: On three separate occasions, in a single-blind, randomized, and cross-over design, 13 recreationally active participants underwent a 30-min TENS protocol, before performing a 5-km cycling TT. TENS was applied to the quadriceps prior to exercise under the following conditions; control (CONT), placebo with sham TENS application (PLAC), and an experimental condition with TENS application (TENS). Quadriceps fatigue was assessed with magnetic femoral nerve stimulation assessing changes in potentiated quadriceps twitch force at baseline, pre and post exercise. Subjective scores of exertion, affect and pain were taken every 1-km.Results: During TTs, application of TENS did not influence pain perceptions (P = 0.68, = 0.03). There was no significant change in mean power (P = 0.16, = 0.16) or TT duration (P = 0.17, = 0.14), although effect sizes were large for these two variables. Changes in power output were not significant but showed moderate effect sizes at 500-m ( = 0.10) and 750-m ( = 0.10). Muscle recruitment as inferred by electromyography data was not significant, but showed large effect sizes at 250-m ( = 0.16), 500-m ( = 0.15), and 750-m ( = 0.14). This indicates a possible effect for TENS influencing performance up to 1-km.Discussion: These findings do not support the use of TENS to improve 5-km TT performance.
Highlights
Afferent information from exercising muscle contributes to the sensation of exercise-induced muscle pain
This study aimed to investigate the effect of Transcutaneous electrical nerve stimulation (TENS) on exercise-induced muscle pain, pacing strategy, and performance during a 5-km cycling time trial (TT)
There was no significant change in mean power (P = 0.16, η2p = 0.16) or TT duration (P = 0.17, η2p = 0.14), effect sizes were large for these two variables
Summary
Afferent information from exercising muscle contributes to the sensation of exercise-induced muscle pain. Exercise typically augments mechanical and chemical stimuli within the muscle, sensitizing, and activating nociceptive group III and IV afferent muscle fibers These communicate information on actual or potential muscle damage to the central nervous system (O’Connor and Cook, 1999). Once nociceptive signals and perceptions of pain become prominent, effort will be regulated to maintain discomfort at a tolerable level (Swart et al, 2012; Edwards and Polman, 2013; Mauger, 2014) This concept of a “sensory tolerance limit” (Gandevia, 2001; Hureau et al, 2016), likely occurs to prevent excessive physiological harm by limiting levels of fatigue (Amann et al, 2009). There is merit for any analgesic intervention during self-paced exercise to adjust perceptions of exercise-induced pain allowing for an increased intensity (and possibly performance), before perceptions become prominent
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
