–reconstructed patients. 7 Poor neuromuscular function of the gluteal muscles has also been related to altered frontal hip and knee plane motion 2 , 3 and decreased subjective knee function. 8 Due to their relationship between gluteal weakness and poor subjective and objective functional measurements, optimizing
Daniel Gilfeather, Grant Norte, Christopher D. Ingersoll, and Neal R. Glaviano
Mehdi Kordi, Len Parker Simpson, Kevin Thomas, Stuart Goodall, Tom Maden-Wilkinson, Campbell Menzies, and Glyn Howatson
elite track cyclists has been associated with maximal voluntary force, 5 and there is evidence suggesting that strength training can elicit positive improvements in W ′. 15 – 17 These findings could suggest that indices of neuromuscular function could be positively related to the W ′, 18 , 19 but
Nick Dobbin, Cari Thorpe, Jamie Highton, and Craig Twist
-being and neuromuscular function was observed, which was negatively associated with several performance variables including relative distance, high-speed running, and number of repeated high-intensity efforts. 8 It is important to note that rugby sevens and rugby league both involve contact, which will
Gregory M. Gutierrez, Nicole D. Jackson, Kristin A. Dorr, Sarah E. Margiotta, and Thomas W. Kaminski
Lateral ankle sprains occur more frequently than any other orthopedic injury. Athletes often report sustaining more injuries late in competition when fatigue is present.
To evaluate neuromuscular function of the ankle musculature after fatigue. Design: Experimental, pretest-posttest.
Ten female and 9 male college-aged subjects.
Fatigue was induced via continuous concentric and eccentric muscle actions of the ankle: inversion (INV), eversion (EV), plantar flexion (PF), and dorsiflexion (DF).
Main Outcome Measures:
Peak torque (PT), peak EMG, and median frequency (MF) were calculated prefatigue and postfatigue in the tibialis anterior (TA), peroneus longus (PER), and lateral gastrocnemius (GAS) muscles.
Main effects were noted for test (P < 0.0125) in all statistical tests performed indicating changes in PT, peak EMG, and MF after fatigue.
A significant decrease in MF of the PER muscle after PF fatigue and corresponding with a decreased firing rate, may be of importance, especially with regard to the role in countering the violent moment seen with inversion ankle sprains.
Dean Norris, David Joyce, Jason Siegler, James Clock, and Ric Lovell
is a multifactorial construct, a variety of monitoring strategies are often employed within the professional setting, such as markers of muscle damage, neuromuscular function (NF), endocrine responses, immune status, and psychological well-being. 3 , 4 While informative, due to cost and time
Gregory Roe, Joshua Darrall-Jones, Kevin Till, Padraic Phibbs, Dale Read, Jonathon Weakley, and Ben Jones
To evaluate changes in performance of a 6-s cycle-ergometer test (CET) and countermovement jump (CMJ) during a 6-wk training block in professional rugby union players.
Twelve young professional rugby union players performed 2 CETs and CMJs on the 1st and 4th mornings of every week before the commencement of daily training during a 6-wk training block. Standardized changes in the highest score of 2 CET and CMJ efforts were assessed using linear mixed modeling and magnitude-based inferences.
After increases in training load during wk 3 to 5, moderate decreases in CMJ peak and mean power and small decreases in flight time were observed during wk 5 and 6 that were very likely to almost certainly greater than the smallest worthwhile change (SWC), suggesting neuromuscular fatigue. However, only small decreases, possibly greater than the SWC, were observed in CET peak power. Changes in CMJ peak and mean power were moderately greater than in CET peak power during this period, while the difference between flight time and CET peak power was small.
The greater weekly changes in CMJ metrics in comparison with CET may indicate differences in the capacities of these tests to measure training-induced lower-body neuromuscular fatigue in rugby union players. However, future research is needed to ascertain the specific modes of training that elicit changes in CMJ and CET to determine the efficacy of each test for monitoring neuromuscular function in rugby union players.
Rich D. Johnston, Tim J. Gabbett, David G. Jenkins, and Michael J. Speranza
To assess the impact of different repeated-high-intensity-effort (RHIE) bouts on player activity profiles, skill involvements, and neuromuscular fatigue during small-sided games.
22 semiprofessional rugby league players (age 24.0 ± 1.8 y, body mass 95.6 ± 7.4 kg).
During 4 testing sessions, they performed RHIE bouts that each differed in the combination of contact and running efforts, followed by a 5-min off-side small-sided game before performing a second bout of RHIE activity and another 5-min small-sided game. Global positioning system microtechnology and video recordings provided information on activity profiles and skill involvements. A countermovement jump and a plyometric push-up assessed changes in lower- and upper-body neuromuscular function after each session.
After running-dominant RHIE bouts, players maintained running intensities during both games. In the contact-dominant RHIE bouts, reductions in moderate-speed activity were observed from game 1 to game 2 (ES = –0.71 to –1.06). There was also moderately lower disposal efficiency across both games after contact-dominant RHIE activity compared with running-dominant activity (ES = 0.62–1.02). Greater reductions in lower-body fatigue occurred as RHIE bouts became more running dominant (ES = –0.01 to –1.36), whereas upper-body fatigue increased as RHIE bouts became more contact dominant (ES = –0.07 to –1.55).
Physical contact causes reductions in running intensity and the quality of skill involvements during game-based activities. In addition, the neuromuscular fatigue experienced by players is specific to the activities performed.
Steven M. Davi, Colleen K. Woxholdt, Justin L. Rush, Adam S. Lepley, and Lindsey K. Lepley
quadriceps health as it is unable to provide context regarding the complexity of quadriceps neuromuscular function over the entirety of contraction. Utilizing techniques capable of evaluating the complexity of quadriceps neuromuscular function over the duration of contraction is key to progressing our
Mitchell Naughton, Joanna Miller, and Gary J. Slater
potential to adversely affect neuromuscular function and prolong athletic recovery. It is well known that high-intensity and/or unaccustomed eccentric exercise causes EIMD through exposure to an inappropriate level of mechanical stress. 6 EIMD results in soreness, myofibrillar disruption, and release of
Dale I. Lovell, Ross Cuneo, and Greg C. Gass
This study examined the effect of aerobic training on leg strength, power, and muscle mass in previously sedentary, healthy older men (70–80 yr). Training consisted of 30–45 min of cycle ergometry at 50–70% maximal oxygen consumption (VO2max), 3 times weekly for 16 wk, then 4 wk detraining, or assignment to a nontraining control group (n = 12 both groups). Training increased leg strength, leg power, upper leg muscle mass, and VO2max above pretraining values (21%, 12%, 4%, and 15%, respectively; p < .05). However, all gains were lost after detraining, except for some gain in VO2max. This suggests that cycle ergometry is sufficient stimulus to improve neuromuscular function in older men, but gains are quickly lost with detraining. For the older population cycle ergometry provides the means to not only increase aerobic fitness but also increase leg strength and power and upper leg muscle mass. However, during periods of inactivity neuromuscular gains are quickly lost.