Please cite this article in press as: Taylor T, et al. The impact of neuromuscular electrical stimulation on recovery after intensive, muscle damaging, maximal speed training in professional team sports players. J Sci Med Sport (2014), http://dx.doi.org/10.1016/j.jsams.2014.04.004 ARTICLE IN PRESS G Model JSAMS-1018; No. of Pages 5 Journal of Science and Medicine in Sport xxx (2014) xxx–xxx Contents lists available at ScienceDirect Journal of Science and Medicine in Sport journal h om epage: www.elsevier.com/locate/jsams Original research The impact of neuromuscular electrical stimulation on recovery after intensive, muscle damaging, maximal speed training in professional team sports players Tom Taylor a,d , Daniel J. West c , Glyn Howatson c , Chris Jones a , Richard M. Bracken a , Thomas D. Love a , Christian J. Cook b , Eamon Swift d , Julien S. Baker e , Liam P. Kilduff a,∗ a Applied Science, College of Engineering, Swansea University, UK b School of Sport, Health and Exercise, Bangor University, UK c Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, UK d The Head of Sports Science at West Ham United Football Club, UK e Institute of Clinical Exercise and Health Science, School of Science, Faculty of Science and Technology, University of the West of Scotland, UK a r t i c l e i n f o Article history: Received 23 August 2013 Received in revised form 6 February 2014 Accepted 4 April 2014 Available online xxx Keywords: Performance Testosterone Creatine kinase Cortisol a b s t r a c t Objectives: During congested fixture periods in team sports, limited recovery time and increased travel hinder the implementation of many recovery strategies; thus alternative methods are required. We exam- ined the impact of a neuromuscular electrical stimulation device on 24-h recovery from an intensive training session in professional players. Design: Twenty-eight professional rugby and football academy players completed this randomised and counter-balanced study, on 2 occasions, separated by 7 days. Methods: After baseline perceived soreness, blood (lactate and creatine kinase) and saliva (testosterone and cortisol) samples were collected, players completed a standardised warm-up and baseline coun- termovement jumps (jump height). Players then completed 60 m × 50 m maximal sprints, with 5 min recovery between efforts. After completing the sprint session, players wore a neuromuscular electrical stimulation device or remained in normal attire (CON) for 8 h. All measures were repeated immediately, 2 and 24-h post-sprint. Results: Player jump height was reduced from baseline at all time points under both conditions; however, at 24-h neuromuscular electrical stimulation was significantly more recovered (mean ± SD; neuromus- cular electrical stimulation -3.2 ± 3.2 vs. CON -7.2 ± 3.7%; P < 0.001). Creatine kinase concentrations increased at all time points under both conditions, but at 24-h was lower under neuromuscular electrical stimulation (P < 0.001). At 24-h, perceived soreness was significantly lower under neuromuscular elec- trical stimulation, when compared to CON (P = 0.02). There was no effect of condition on blood lactate, or saliva testosterone and cortisol responses (P > 0.05). Conclusions: Neuromuscular electrical stimulation improves recovery from intensive training in pro- fessional team sports players. This strategy offers an easily applied recovery strategy which may have particular application during sleep and travel. © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved. 1. Introduction In sports such as soccer and rugby union, more competitions have increased the number of fixtures played each season. Soc- cer players may complete up to 60 fixtures during the season 1 and often with as little as 2 days of recovery between games. 2 ∗ Corresponding author. E-mail address: L.kilduff@swansea.ac.uk (L.P. Kilduff). Moreover, the growing fixture demand is concomitant with an increased frequency of travel between matches. In soccer and rugby union, a single match can increase the circulating concentrations of intracellular proteins, 3–5 which is indicative of skeletal muscle damage. 3,4 For example, Cunniffe et al. 4 reported large increases in creatine kinase (CK) at 14 (∼+227%) and 38 h (∼+45%) after an international rugby union match. In addition, Thorpe and Sunderland 5 also found ∼84% and 238% increases in CK and myoglobin respectively, immediately after a soccer match. Muscle damage, together with an associated http://dx.doi.org/10.1016/j.jsams.2014.04.004 1440-2440/© 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.