Journal of Sports Sciences

ISSN: 0264-0414 (Print) 1466-447X (Online) Journal homepage: http://www.tandfonline.com/loi/rjsp20

Day 1. Free Communications – Sport and Performance To cite this article: (2015) Day 1. Free Communications – Sport and Performance, Journal of Sports Sciences, 33:sup1, s17-s20, DOI: 10.1080/02640414.2015.1110316 To link to this article: http://dx.doi.org/10.1080/02640414.2015.1110316

Published online: 25 Nov 2015.

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Date: 26 January 2016, At: 10:23

Journal of Sports Sciences, 2015 Vol. 33, Supplement 1, s17–s20, http://dx.doi.org/10.1080/02640414.2015.1110316

Day 1. Free Communications – Sport and Performance

D1.S3.2(1). Effect of hypoxia on jointspecific power production during maximal cycling OWEN JEFFRIES1,2*, THOMAS KORFF2 & LEE M. ROMER2 Downloaded by [University of California, San Diego] at 10:23 26 January 2016

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St Mary’s University; 2Brunel University *Corresponding author: [email protected] @0o0_jay The relative contribution of lower limb muscle groups changes throughout sustained, high-intensity cycle exercise (Sanderson and Black, 2003, Journal of Sports Sciences, 21, 191–199). This suggests that exercise-induced fatigue is muscle group specific. We asked whether the additional muscular stress associated with hypoxia would alter the muscle specificity of fatigue. With institutional ethics approval, nine male cyclists (mean ± SD VO2max 61.2 ± 3.8 ml · kg−1 · min−1) pedalled to the limit of tolerance at a fixed work rate (60% of the difference between VO2max and gas-exchange threshold: 306 ± 14 W) and fixed cadence (88 ± 2 rpm) in two conditions: normoxia (FIO2 0.21, SaO2 95 ± 1%) and hypoxia (FIO2 0.15, SaO2 85 ± 2%). Pedal forces, joint kinematics and surface EMG activity were recorded throughout exercise. Joint action powers (hip extension, hip flexion, knee extension, knee flexion, plantar flexion and dorsi flexion) were derived using inverse dynamics. Neuromuscular activation (gluteus maximus, vastus lateralis, biceps femoris, gastrocnemius and soleus) was quantified using EMG root mean square (EMGRMS). For both conditions, data were averaged over the first, middle and final 30 s of the corresponding hypoxia trial to allow for isotime comparisons. Data were also averaged over the final 30 s of the normoxia trial to enable endexercise comparisons. Exercise time was reduced in hypoxia versus normoxia (4.1 ± 0.2 vs. 10.1 ± 1.1 min, P < 0.05). Hip extension power increased throughout exercise in normoxia, whereas knee extension power decreased. The changes in endexercise joint action powers were reduced in hypoxia versus normoxia (113 vs. 127% for hip extension, P < 0.05; 92 vs. 87% for knee extension, P < 0.05), but were relatively well preserved at exercise isotime (P > 0.05 for middle and final 30 s). Gluteus

© 2015 Taylor & Francis

maximus and biceps femoris EMGRMS increased throughout exercise in both conditions. The increases in end-exercise EMGRMS were similar in both conditions, but were elevated in hypoxia versus normoxia at exercise isotime (P < 0.05). In conclusion, time-dependent changes in joint action powers during sustained, high-intensity cycle exercise are relatively well preserved in hypoxia. Rates of rise in electromyographic activity for selected muscles of the lower limb are increased in hypoxia, presumably to ensure the maintenance of joint action power distribution. The results suggest that joint power distribution is a robust property of cycling and is largely independent of arterial hypoxaemia. The increased muscular stress associated with hypoxia appears to require a disproportionate increase in hip-extensor activity to maintain a normal coordinative pattern.

D1.S3.2(2). The effect of competition and practice climate on cognitive performance during moderate and high-intensity exercise. A bioinformational perspective MIKE SMITH*, NEIL CLARKE, MARTIN COX & MICHAEL DUNCAN Coventry University *Corresponding author: [email protected] @cu_msmith The relationship between exercise intensity and cognitive performance has been explained from a uni-dimensional perspective in the form of an inverted-U (McMorris et al., 2011, Physiology & Behavior, 102, 421–428). However, a recent metaanalysis failed to fully support this proposal suggesting that further research is required (McMorris et al., 2015, Physiology & Behavior, 141,180–189). This study examined the effects of “in-event” changes in exercise intensity on cognitive performance (Pontifex et al., 2009, Psychophysiology, 46, 379–387). Following approval by the University Ethics Committee, 14 physically active adults (9 males and 5 females, mean age ± SD = 21 ± 2 years), completed two incremental running

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exercise trials (perceived competition or perceived practice) in a counterbalanced order. Performance _ 2max and measures were recorded at rest, 70% VO _ 90% VO 2max. Salivary cortisol, resting systolic blood pressure (SBP) and diastolic blood pressure (DBP) were taken pre- and post-competition/practice instructions. During exercise, Rating of Perceived Exertion (RPE) (6–20 scale), heart rate, blood lactate, cognitive and somatic anxiety and self-confidence intensity and direction scores and cognitive performance were recorded. The results indicated that SBP significantly increased pre to post instructions in both the practice (P = 0.05) and the competition (P = 0.001) conditions. Heart rate post instructions (P = 0.0001), at 70% _ 2 max (P = _ 2max (P = 0.001) and 90% VO VO 0.0001) was significantly higher in the competitive condition compared to the practice condition. Increase in salivary cortisol (P = 0.044) and RPE was significantly higher in the competitive condition compared to the practice condition (P = 0.023). There was no change in blood lactate (P > 0.05) between conditions. Cognitive anxiety intensity was significantly higher in the competition compared _ to the practice condition, at both 70% and 90% VO 2max (P = 0.001). Scores for cognitive anxiety direction were significantly more debilitative in the competitive condition compared to the practice condition (P = 0.013). Cognitive performance (i.e. visual discrimination) response times were significantly _ 2max (P = smaller at rest compared to 70% VO _ 2max (P = 0.002) and at 70% 0.001) and 90% VO _VO 2max compared to 90% VO _ 2max (P = 0.04) in the competitive condition. This study found that cognitive performance is more negatively affected when physiological arousal and cognitive anxiety are at their highest in the competitive condition. The results can be explained using the Catastrophe Model (Fazey and Hardy, 1991, British Journal of Psychology, 82, 163–178; Lang, 1979, Psychophysiology, 16, 495–512.

D1.S3.2(3). The effects of hypohydration and hot environmental conditions on cognitive performance following field hockey-specific exercise SIMON COOPER*, HANNAH MACLEOD & CAROLINE SUNDERLAND Nottingham Trent University *Corresponding author: [email protected]

It has previously been suggested that heat exposure and hypohydration have negative effects on cognitive performance (Baker et al., 2007, Medicine and Science in Sports and Exercise, 39, 1114–1123), which may impact on sporting performance. Therefore, the aim of the present study was to examine the independent effects of heat stress and hypohydration on cognitive performance in elite female field hockey players. Following ethical approval, eight healthy unacclimatised elite field hockey players (age: 22.0 ± 3.0 years; height: 1.68 ± 0.05 m; body mass: 63.1 ± 6.0 kg; VO2max: 54.6 ± 3.2 ml · kg−1 · min−1) with 2–3 years experience of international field hockey participated in the study. Following familiarisation, participants completed four experimental trials: two in hot environmental conditions (33.3 ± 0.1°C, 59 ± 1% RH), with and without ad libitum water intake (HF, HNF), and two in moderate environmental conditions (16.0 ± 3.0°C, 53 ± 2% RH), with and without ad libitum water intake (MF, MNF). Following 60min exposure to the environmental conditions (hot or moderate), participants rested for 60 min in ambient conditions before completing the Field Hockey Intermittent Treadmill Protocol (FHITP, MacLeod and Sunderland, 2012, Journal of Sports Medicine and Physical Fitness, 52, 351–358) in the relevant environmental conditions (hot or moderate). A battery of cognitive function tests (visual search test, Stroop test and Sternberg paradigm) were completed at baseline and following the FHITP. Data were analysed in R using four-way repeated measures ANOVA (heat × hydration status × time × test level) and significance was accepted as P < 0.05. On the visual search test, participants were faster overall in the heat (1218 vs. 1305 ms, P = 0.003), but upon further analysis this was only on the more complex level (1941 vs. 2104 ms, P = 0.001), whereas response times on the baseline level were unaffected (P = 0.982). Response times were also quicker in the heat on the Sternberg paradigm (463 vs. 473 ms, P = 0.024), though this effect was not different between test levels (P = 0.062). Heat exposure also enhanced accuracy across the trial on the complex level of the Sternberg paradigm (by 1.9%, P = 0.004), whereas accuracy remained unchanged across the trial in the moderate environment. There was no effect of environmental temperature on Stroop test performance, or an effect of hydration status on any of the markers of cognitive performance (all P > 0.05). Overall, the findings suggest that in elite field hockey players exposure to heat enhances response times and/ or accuracy on a battery of cognitive function tests. However, hypohydration (by 2% body mass) does not appear to affect cognitive performance in elite field hockey players.

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D1.S3.2(4). Knowledge of the exercise end point alters pacing during simulated rugby league match play THOMAS MULLEN*, CRAIG TWIST & JAMIE HIGHTON

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University of Chester *Corresponding author: [email protected] @tmullen_sport The duration of an exercise bout has a marked impact on players’ pacing profiles during elite rugby league matches (Waldron et al., 2013, International Journal of Sports Physiology and Performance, 8, 157–164). However, the influence of knowing the exercise duration on pacing during team sports remains unknown. Accordingly, the aim of this study was to examine the effect of manipulated understanding of the exercise end point on pacing profiles during simulated rugby league match play. After institutional ethical approval, 13 male rugby players (age = 22 ± 3 years, stature = 1.77 ± 0.02 m, body mass = 82.7 ± 8.0 kg, predicted _ 2max = 54.0 ± 4.6 ml · kg−1 · min−1) performed VO three trials, in a randomised order, of the same rugby league match simulation protocol (RLMSP-i). All trials consisted of 2 × 23 min exercise bouts, but with different instructions provided to the participant before each. Participants were (i) informed they would perform 2 × 23 min bouts (control trial [CON]), (ii) were not aware of the duration of the RLMSP-i (unknown trial [UN]) or (iii) told they would perform only 1 × 23 min bout (deception trial [DEC]). Movement distance and speed (via a global positioning system device), and blood lactate concentration were measured during all trials, with session rating of perceived exertion (sRPE) recorded immediately after the protocol. Repeated measures ANOVAs, with post-hoc paired samples t-tests were conducted. Maximum sprint speeds were significantly lower during the UN trial (P < 0.05) compared to CON and DEC. An “end-spurt” in sprint speed was observed at the end of bout two in CON (23.5 ± 1.5 km · h−1, P < 0.05) and the end of bout one in DEC (23.8 ± 1.6 km · h−1, P < 0.05), with none apparent in UN. This coincided with a peak in blood lactate concentration at the end of bout two in CON (5.6 ± 3.0 mmol · L−1, P < 0.05), and at the end of bout one for DEC (5.7 ± 2.0 mmol · L−1, P < 0.05), with no significant changes throughout the UN trial (P < 0.05). The sRPE for DEC (7.0 ± 1.6) was significantly higher than CON (5.6 ± 1.7) and UN (4.8 ± 2.6; P < 0.05). These results suggest that an individual’s understanding of the exercise

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end point alters their adopted pacing strategy and associated pattern of physiological exertion during a simulated rugby league match. This has implications for practitioners when informing players of their exercise duration in team sports that involve multiple interchanges during a match.

D1.S3.2(5). Ineffective and effective coping strategies associated with professional rugby union referees DENISE HILL*, RUTH SENIOR & TOM YOUNG University of Gloucestershire *Corresponding author: [email protected] @psychskills This study extends the work of Neil et al. (2013, Sport and Exercise Psychology Review, 9, 22–41) by exploring the psychological characteristics of rugby union officiating excellence. More specifically, it aimed to examine the sources of stress, appraisal mechanism, emotional response and coping strategies associated with optimal and unsuccessful (i.e. choking) rugby union refereeing performance under pressure. A transcendental phenomenological approach was adopted (see Giorgi and Giorgi, 2008, In J. A. Smith (Eds.), Qualitative Psychology: A Practical Guide to Research Methods (pp. 26–52), London: Sage) in order to address the aims of the study. Accordingly, after ethics approval was gained from the lead author’s Institution, seven professional rugby union referees (i.e. from the National Panel of Match Officials) completed individual semi-structured interviews in which their experiences of performing under pressure were considered in detail. The study revealed that the importance/context of match, interpersonal conflict, self-presentational concerns, expectations, unfamiliarity and overload were the main sources of stress the elite referees were required to cope with before and during games. The latter two stressors (i.e. unfamiliarity and overload) were noted to hold the most potential to effect refereeing performance detrimentally, for they tended to elicit a threat appraisal and negative emotional affect which were difficult to manage. It was identified that the problem- and emotional-focused coping strategies of mental preparation, adopting a task/process focus, emotional control, acceptance, ownership, reflection and informational social support were effective in managing the stressors experienced by the referees. Whereas avoidance coping, misplaced/inappropriate impression management and reactive control of others were identified as ineffective coping strategies

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which often led to under-performance and choking under pressure. Accordingly, the study offers a number of evidence-based recommendations that can inform the work of those supporting the development of rugby union referees.

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D1.S3.2(6). The effect of contact type on internal and external demands during a rugby league match simulation protocol JONATHAN NORRIS*, STEPHEN HUGHES, JAMIE HIGHTON & CRAIG TWIST University of Chester *Corresponding author: [email protected] @jontynorris Physical contact is a fundamental component of rugby league that alters the internal and external responses to intermittent running (Mullen, Highton, and Twist, 2015, International Journal of Sports Physiology and Performance, doi: 10.1123/ ijspp.2014-0609). Different methods can be used to replicate physical contact in a testing and training environment. Therefore, this study examined how the type of physical contact influences the internal and external demands during and after a simulated rugby league match. With institutional ethics approval, 11 male university rugby league players (mean age 21.8 years, s = 1.3; body mass 86.4 kg, s = 6.9; stature 186.5 cm, s = 7.4; predicted V̇ O2max

47.9 ml · kg−1 · min−1, s = 2.1) performed two randomised trials of a rugby league movement simulation protocol (RLMSP-i; Waldron, Highton, and Twist, 2013, International Journal of Sports Physiology and Performance, 8, 483–489) using a soft (~35 kg) tackle bag (BAG) and a weighted (~75 kg) tackle sled (SLED) to replicate contact demands. Locomotive rate, sprint speed, summated heart rate and RPE were analysed over the total simulation. Countermovement jump (CMJ) was also measured before and immediately after each trial. Sprint speed into contact was faster during BAG (16.1 km · h−1, s = 1.5) compared to SLED (14.8 km · h−1, s = 1.1; ES ± 90% CI: 1.03 ± 0.92). However, there was less high-intensity running during BAG (mean 1278 m, s = 112) compared to SLED (mean 1308 m, s = 120; ES ± 90% CI: −0.23 ± 0.35). SLED increased time that heart rate was between 90% and 100% HRpeak (mean 12:58 min:s, s = 13:21) compared to BAG (mean 6:44 min:s, s = 8:06; ES ± 90% CI: −0.41 ± 0.48) and resulted in a higher RPE (mean 15.5, s = 1.9) than BAG (mean 14.8, s = 1.8; ES ± 90% CI: −0.34 ± 0.26). Larger (ES ± 90% CI: 0.60 ± 0.69) decrements in CMJ were also observed during SLED (mean 5.9%, s = 4.9%) compared to BAG (mean 2.6%, s = 5.4). Changing the type of contact subtly alters the internal and external demands during a rugby league match simulation protocol. Using a standard soft tackle bag results in a faster sprint speed to contact, but also reduces overall high-intensity running. Conversely, a heavier tackle object increases the internal load and results in greater lower limb neuromuscular fatigue as reflected by the decrease in CMJ performance.

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