bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyponatremia in the 2009 161-km Western States Endurance Run
Authors: Hoffman Martin D. , Stuempfle Kristin J. , Rogers Ian R. , Weschler Louise B. , Hew-Butler Tamara 
Published: August 2016

Purpose:To determine the incidence of exercise-associated hyponatremia (EAH), the associated biochemical measurements and risk factors for EAH, and whether there is an association between postrace blood sodium concentration ([Na+]) and changes in body mass among participants in the 2009 Western States Endurance Run, a 161-km mountain trail run.Methods:Change in body mass, postrace [Na+], and blood creatine phosphokinase (CPK) concentration, and selected runner characteristics were evaluated among consenting competitors.Results:Of the 47 study participants, 14 (30%) had EAH as defined by a postrace [Na+] <135 mmol/L. Postrace [Na+] and percent change in body mass were directly related (r = .30, P = .044), and 50% of those with EAH had body mass losses of 3–6%. EAH was unrelated to age, sex, finish time, or use of nonsteroidal anti-inflammatory drugs during the run, but those with EAH had completed a smaller (P = .03) number of 161-km ultramarathons. The relationship of CPK levels to postrace [Na+] did not reach statistical significance (r = –.25, P = .097).Conclusions:EAH was common (30%) among finishers of this 161-km ultramarathon and it was not unusual for those with EAH to be dehydrated. As such, changes in body mass should not be relied upon in the assessment for EAH during 161-km ultramarathons.
Current Match-Analysis Techniques’ Underestimation of Intense Periods of High-Velocity Running
Authors: Varley Matthew C. , Elias George P. , Aughey Robert J. 
Published: August 2016

Purpose:To compare the peak 5-min period of high-velocity running (HiVR) during a soccer match using a predefined vs a rolling time interval.Methods:Player movement data were collected from 19 elite Australian soccer players over 11 competitive matches (77 individual match files) using a 5-Hz global-positioning system. Raw velocity data were analyzed to determine the period containing the greatest HiVR distance per match half and the distance covered in the subsequent epoch. Intervals were identified using either a predefined (distance covered in 5 min at every 5-min time point) or rolling (distance covered in 5 min from every time point) method. The percentage difference ± 90% confidence limits were used to determine differences between methods.Results:Predefined periods underestimated peak distance covered by up to 25% and overestimated the subsequent epoch by up to 31% compared with rolling periods. When the distance decrement between the peak and following period was determined, there was up to a 52% greater reduction in running performance using rolling periods than predefined ones.Conclusions:It is recommended that researchers use rolling as opposed to predefined periods when determining specific match intervals because they provide a more accurate representation of the HiVR distance covered. This will avoid underestimation of both match running distance and the decrement in running performance after an intense period of play. This may have practical implications for not only researchers but also staff involved in a club setting who use this reduction as evidence of transient fatigue during a match.
Even Between-Lap Pacing Despite High Within-Lap Variation During Mountain Biking
Authors: Martin Louise , Lambeth-Mansell Anneliese , Beretta-Azevedo Liane , Holmes Lucy A. , Wright Rachel , Gibson Alan St Clair 
Published: August 2016

Purpose:Given the paucity of research on pacing strategies during competitive events, this study examined changes in dynamic high-resolution performance parameters to analyze pacing profiles during a multiple-lap mountain-bike race over variable terrain.Methods:A global-positioning-system (GPS) unit (Garmin, Edge 305, USA) recorded velocity (m/s), distance (m), elevation (m), and heart rate at 1 Hz from 6 mountain-bike riders (mean ± SD age = 27.2 ± 5.0 y, stature = 176.8 ± 8.1 cm, mass = 76.3 ± 11.7 kg, VO2max = 55.1 ± 6.0 mL · kg−1 . min−1) competing in a multilap race. Lap-by-lap (interlap) pacing was analyzed using a 1-way ANOVA for mean time and mean velocity. Velocity data were averaged every 100 m and plotted against race distance and elevation to observe the presence of intralap variation.Results:There was no significant difference in lap times (P = .99) or lap velocity (P = .65) across the 5 laps. Within each lap, a high degree of oscillation in velocity was observed, which broadly reflected changes in terrain, but high-resolution data demonstrated additional nonmonotonic variation not related to terrain.Conclusion:Participants adopted an even pace strategy across the 5 laps despite rapid adjustments in velocity during each lap. While topographical and technical variations of the course accounted for some of the variability in velocity, the additional rapid adjustments in velocity may be associated with dynamic regulation of self-paced exercise.
The Relationship Between Freely Chosen Cadence and Optimal Cadence in Cycling
Authors: Emanuele Umberto , Horn Tamara , Denoth Jachen 
Published: August 2016

Purpose:The main aim of this study was to compare the freely chosen cadence (FCC) and the cadence at which the blood lactate concentration at constant power output is minimized (optimal cadence [Copt]). The second aim was to examine the effect of a concomitant change of road incline and body position on FCC, the maximal external power output (Pmax), and the corresponding Copt.Methods:FCC, Copt, and Pmax were analyzed under 2 conditions: cycling on level ground in a dropped position (LGDP) and cycling uphill in an upright position (UHUP). Seven experienced cyclists participated in this study. They cycled on a treadmill to test the 2 main hypotheses: Experienced cyclists would choose an adequate cadence close to Copt independent of the cycling condition, and FCC and Copt would be lower and Pmax higher for UHUP than with LGDP.Results:Most but not all experienced cyclists chose an adequate cadence close to Copt. Independent of the cycling condition, FCC and Copt were not statistically different. FCC (82.1 ± 11.1 and 89.3 ± 10.6 rpm, respectively) and Copt (81.5 ± 9.8 and 87.7 ± 10.9 rpm, respectively) were significantly lower and Pmax was significantly higher (2.0 ± 2.1%) for UHUP than for LGDP.Conclusion:Most experienced cyclists choose a cadence near Copt to minimize peripheral fatigue at a given power output independent of the cycling condition. Furthermore, it is advantageous to use a lower cadence and a more upright body position during uphill cycling.
Repeated High-Intensity Running and Sprinting in Elite Women’s Soccer Competition
Authors: Gabbett Tim J. , Wiig Håvard , Spencer Matt 
Published: August 2016

Background:To the authors’ knowledge, no study has investigated the concurrent repeated, high-intensity (RHIA) and repeated-sprint activity (RSA) of intermittent team-sport competition.Purpose:In this study, they report on the RSA of elite women’s football competition. In addition, they describe the nature of RHIA (eg, striding and sprinting activities) that involve a high energy cost and are associated with short (ie, ≤20 s) recovery periods.Methods:Thirteen elite women soccer players underwent video-based time–motion analysis on 34 occasions during national and international standard matches. RSA and RHIA were defined as successive (ie, 2) sprints or striding and sprinting efforts that occurred with ≤20 s between efforts.Results:The number of RSA and RHIA bouts performed was similar between the first and second halves of matches. Sprinting and striding/sprinting durations tended to remain relatively stable irrespective of the number of efforts in an RSA or RHIA bout or the period of play. However, recovery duration between efforts increased in the second half, when a greater number of efforts were performed per bout.Conclusion:These findings suggest that first- to second-half reductions in RHIA and RSA do not occur in elite women’s soccer competition. However, players increase the amount of low-intensity recovery undertaken between RHIA and RSA efforts, most likely in an attempt to maintain RHIA and RSA performance. These findings emphasize the importance of RSA and RHIA to elite women’s soccer and highlight the importance of training this quality to prevent reductions in performance during competitive match play.
Comparison of Agility Demands of Small-Sided Games in Elite Australian Football
Authors: Davies Michael J. , Young Warren , Farrow Damian , Bahnert Andrew 
Published: August 2016

Purpose:To compare the agility demands of 4 small-sided games (SSGs) and evaluate the variability in demands for elite Australian Football (AF).Methods:Fourteen male elite Australian Football League (AFL) players (mean ± SD; 21.7 ± 3.1 y, 189.6 ± 9.0 cm, 88.7 ± 10.0 kg, 39.4 ± 57.1 games) completed 4 SSGs of 3 × 45-s bouts each with modified designs. Video notational analysis, GPS at 5 Hz, and triaxial accelerometer data expressed the external player loads within games. Three comparisons were made using a paired t test (P < .05), and magnitudes of differences were reported with effect size (ES) statistics.Results:Reduced area per player (increased density) produced a small increase in total agility maneuvers (SSG1, 7.2 ± 1.3; SSG2, 8.8 ± 4.1), while a large 2D player load was accumulated (P < .05, ES = 1.22). A reduction in players produced a moderate (ES = 0.60) total number of agility maneuvers (SSG 3, 11.3 ± 6.1; SSG 2, 8.3 ± 3.6); however, a greater variability was found. The implementation of a 2-handed-tag rule resulted in a somewhat trivial decline (P > .05, ES = 0.16) in agility events compared with normal AFL tackling rules (SSG 2, 8.3 ± 3.6; SSG 4, 7.8 ± 2.6).Conclusions:SSG characteristics can influence agility-training demand, which can vary considerably for individuals. Coaches should carefully consider SSG design to maximize the potential to develop agility for all players.
A Comparison of Methods to Quantify the In-Season Training Load of Professional Soccer Players
Authors: Scott Brendan R. , Lockie Robert G. , Knight Timothy J. , Clark Andrew C. , Janse de Jonge Xanne A.K. 
Published: August 2016

Purpose:To compare various measures of training load (TL) derived from physiological (heart rate [HR]), perceptual (rating of perceived exertion [RPE]), and physical (global positioning system [GPS] and accelerometer) data during in-season field-based training for professional soccer.Methods:Fifteen professional male soccer players (age 24.9 ± 5.4 y, body mass 77.6 ± 7.5 kg, height 181.1 ± 6.9 cm) were assessed in-season across 97 individual training sessions. Measures of external TL (total distance [TD], the volume of low-speed activity [LSA; <14.4 km/h], high-speed running [HSR; >14.4 km/h], very high-speed running [VHSR; >19.8 km/h], and player load), HR and session-RPE (sRPE) scores were recorded. Internal TL scores (HR-based and sRPE-based) were calculated, and their relationships with measures of external TL were quantified using Pearson product–moment correlations.Results:Physical measures of TD, LSA volume, and player load provided large, significant (r = .71−.84; P < .01) correlations with the HR-based and sRPE-based methods. Volume of HSR and VHSR provided moderate to large, significant (r = .40−.67; P < .01) correlations with measures of internal TL.Conclusions:While the volume of HSR and VHSR provided significant relationships with internal TL, physical-performance measures of TD, LSA volume, and player load appear to be more acceptable indicators of external TL, due to the greater magnitude of their correlations with measures of internal TL.
The Reliability of a 30-s Sprint Test on the Wattbike Cycle Ergometer
Authors: Driller Matthew W. , Argus Christos K. , Shing Cecilia M. 
Published: August 2016

Purpose:To determine the reliability of a 30-s sprint cycle test on the Wattbike cycle ergometer.Methods:Over 3 consecutive weeks, 11 highly trained cyclists (mean ± SD; age 31 ± 6 y, mass 74.6 ± 10.6 kg, height 180.5 ± 8.1cm) completed four 30-s maximal sprints on a Wattbike ergometer after a standardized warmup. The sprint test implemented a “rolling start” that consisted of a 60-s preload (at an intensity of 4.5 W/kg) before the 30-s maximal sprint. Variables determined across the duration of the sprint were peak power (Wpeak), mean power (Wmean), W/kg, mean cadence (rpm), maximum heart rate (n = 10), and postexercise blood lactate.Results:The average intraclass correlation coefficients between trials (2v1, 3v2, 4v3, 4v1) were Wpeak .97 (90%CI .94–.99), Wmean .99 (90%CI .97–1.00), W/kg .96 (90%CI .91–.98), mean cadence .96 (90%CI .92–.99), maximum heart rate .99 (90%CI .97–.99), and postexercise blood lactate .94 (90%CI .87–.98). The average typical error of measurement (expressed as a CV% and absolute value between trials—2v1, 3v2, 4v3, 4v1) was Wpeak 4.9%, 52.7 W; Wmean 2.4%, 19.2 W; W/kg 2.3%, 0.18 W/kg; mean cadence 1.4%, 1.6 rpm; maximum heart rate 0.9%, 1.6 beats/min; and postexercise blood lactate 4.6%, 0.48 mmol/L.Conclusion:A 30-s sprint test on the Wattbike cycle ergometer is highly reproducible in trained cyclists.
Individualization of Time–Motion Analysis: A Case-Cohort Example
Authors: Lovell Ric , Abt Grant 
Published: August 2016

Purpose:To report the intensity distribution of Premier League soccer players’ external loads during match play, according to recognized physiological thresholds. The authors also present a case in which individualized speed thresholds changed the interpretation of time–motion data.Method:Eight outfield players performed an incremental treadmill test to exhaustion to determine the running speeds associated with their ventilatory thresholds. The running speeds were then used to individualize time–motion data collected in 5 competitive fixtures and compared with commonly applied arbitrary speed zones.Results:Of the total distance covered, 26%, 57%, and 17% were performed at low, moderate, and high intensity, respectively. Individualized time– motion data identified a 41% difference in the high-intensity distance covered between 2 players of the same positional role, whereas the player-independent approach yielded negligible (5–7%) differences in total and high-speed distances covered.Conclusions:The authors recommend that individualized speed thresholds be applied to time–motion-analysis data in synergy with the traditional arbitrary approach.
The Effects of 4 Different Recovery Strategies on Repeat Sprint-Cycling Performance
Authors: Argus Christos K. , Driller Matthew W. , Ebert Tammie R. , Martin David T. , Halson Shona L. 
Published: August 2016

Purpose:To evaluate the effectiveness of different recovery strategies on repeat cycling performance where a short duration between exercise bouts is required.Methods:Eleven highly trained cyclists (mean ± SD; age = 31 ± 6 y, mass = 74.6 ± 10.6 kg, height = 180.5 ± 8.1 cm) completed 4 trials each consisting of three 30-s maximal sprints (S1, S2, S3) on a cycle ergometer, separated by 20-min recovery periods. In a counterbalanced, crossover design, each trial involved subjects performing 1 of 4 recovery strategies: compression garments (COMP), electronic muscle stimulation (EMS), humidification therapy (HUM), and a passive control (CON). The sprint tests implemented a 60-s preload (at an intensity of 4.5 W/kg) before a 30-s maximal sprint. Mean power outputs (W) for the 3 sprints, in combination with perceived recovery and blood lactate concentration, were used to examine the effect of each recovery strategy.Results:In CON, S2 and S3 were (mean ± SD) –2.1% ± 3.9% and –3.1% ± 4.2% lower than S1, respectively. Compared with CON, COMP resulted in a higher mean power output from S1 to S2 (mean ± 90%CL: 0.8% ± 1.2%; possibly beneficial) and from S1 to S3 (1.2% ± 1.9%; possibly beneficial), while HUM showed a higher mean power output from S1 to S3 (2.2% ± 2.5%; likely beneficial) relative to CON.Conclusion:The authors suggest that both COMP and HUM may be effective strategies to enhance recovery between repeated sprint-cycling bouts separated by ~30 min.
An Approach to Estimating Gross Efficiency During High-Intensity Exercise
Authors: de Koning Jos J. , Noordhof Dionne A. , Uitslag Tom P. , Galiart Rianna E , Dodge Christopher , Foster Carl 
Published: August 2016

Purpose:Gross efficiency (GE) is coupling power production to propulsion and is an important performance-determining factor in endurance sports. Measuring GE normally requires measuring VO2 during submaximal exercise. In this study a method is proposed to estimating GE during high-intensity exercise.Methods:Nineteen subjects completed a maximal incremental test and 2 GE tests (1 experimental and 1 control test). The GE test consisted of 10 min cycling at 50% peak power output (PPO), 2 min at 25 W, followed by 4 min 100% PPO, 1 min at 25 W, and another 10 min at 50% PPO. GE was determined for the 50%-PPO sections and was, for the second 50%-PPO section, back-extrapolated, using linear regression, to the end of the 100%-PPO bout.Results:Back-extrapolation of the GE data resulted in a calculated GE of 15.8% ± 1.7% at the end of the 100%-PPO bout, in contrast to 18.3% ± 1.3% during the final 2 min of the first 10-min 50%-PPO bout.Conclusion:Back-extrapolation seems valuable in providing more insight in GE during high-intensity exercise.
Effect of Power-Training Intensity on the Contribution of Force and Velocity to Peak Power in Older Adults
Authors: de Vos Nathan J. , Singh Nalin A. , Ross Dale A. , Stavrinos Theodora M. , Orr Rhonda , Singh Maria A. Fiatarone 
Published: August 2016

Objective:To determine the effect of training intensity on the contributions of force and velocity to improvements in peak power (PP) after explosive resistance training in older adults.Methods:112 healthy older adults (69 ± 6 yr) were randomized to explosive resistance training at 20% (G20), 50% (G50), or 80% (G80) maximal strength (1-repetition maximum) for 8–12 wk (twice weekly, 5 exercises, 3 sets of 8 explosive concentric/slow eccentric repetitions) using pneumatic resistance machines or a nontraining control group (CON).Results:Force at peak power (FPP) increased significantly and similarly among training groups compared with CON. Velocity at peak power (VPP) did not improve significantly and remained similar between all groups. Force contributed significantly more to PP production in G80 and G50 than in CON. The change in PP was independently predicted by changes in fat-free mass in G80 and by changes in both FPP and VPP in G50 and G20.Conclusion:Explosive resistance training in older adults results in the ability to produce higher PP outputs with heavier loads without loss of movement velocity. Moderate- to high-intensity training induced a greater relative contribution of force to PP production in this cohort.
Maximal Fitness Testing in Sedentary Elderly at Substantial Risk of Disability: LIFE-P Study Experience
Authors: Church Timothy S. , Gill Thomas M. , Newman Anne B. , Blair Steven N. , Earnest Conrad P. , Pahor Marco 
Published: August 2016

Background:The authors sought to evaluate the acceptability and feasibility of maximal fitness testing in sedentary older individuals at risk for mobility disability.Methods:Maximal cycle-ergometer testing was performed at baseline and 6 and 12 months later in a subset of LIFE-P study participants at the Cooper Institute site. The mean age of the 20 participants (80% female) tested was 74.7 ± 3.4 years. The following criteria were used to determine whether participants achieved maximal effort: respiratory-exchange ratio (RER) ≥1.1, heart rate within 10 beats/min of the maximal level predicted by age, and rating of perceived exertion (RPE) >17.Results:Participants’ mean peak VO2 was 12.1 (3.7) mL · kg–1 · min–1. At baseline testing, only 20% of participants attained an RER ≥1.10, only 35% achieved a peak heart rate within 10 beats of their age-predicted maximum, and 18% had an RPE of >17. Subsequent testing at 6 and 12 months produced similar results.Conclusions:In this pilot study of sedentary older persons at risk for mobility disability, very few participants were able to achieve maximal effort during graded cycle-ergometer testing.
Adherence to Physical Activity Recommendations in Older Adults: An Israeli National Survey
Authors: Netz Yael , Goldsmith Rebecca , Shimony Tal , Ben-Moshe Yosefa , Zeev Aviva 
Published: August 2016

The trend of extended life expectancy along with a sedentary lifestyle is typical in Western cultures.Objective:To explore adherence to physical activity recommendations in older adults in Israel.Methods:A random sample of 1,536 Jews and 316 Arabs age 65+ were interviewed and divided into sufficiently active, insufficiently active, and inactive groups based on official guidelines.Results:Only 36.4% of the Jewish sector and 19.6% of the Arab sector are sufficiently active. Men are more active than women, the secular are more active than the religious among both Jews and Arabs, and more years of education, a higher income, and fewer diseases and medications are related to higher levels of physical activity.Discussion:To slow down biological age decline with physical activity, intervention programs specifically tailored for culturally diverse groups are suggested—for example, recruiting prominent religious leaders to promote physical activity in religious populations.
Physical Activity in Nursing Homes—Barriers and Facilitators: A Cross-Sectional Study
Authors: Kalinowski Sonja , Wulff Ines , Kölzsch Marita , Kopke Kirsten , Kreutz Reinhold , Dräger Dagmar 
Published: August 2016

Purpose:To explore different institutional barriers to and facilitators of physical activity (PA) in nursing homes.Methods:Cross-sectional survey of 40 German nursing homes and 217 nursing-home residents (NHRs; M ± SD age 80 ± 10.2 yr, 55% women, MMSE ≥20). Quantitative data were collected on the structural characteristics of nursing homes and the PA services available.Results:Forms of exercise available were not adequately communicated to residents. Overall participation was below 50%. Awareness was significantly higher in residents with informed relatives (p = .003). A broad range of forms of exercise was generally available (M ± SD 5 ± 2.22, range 0–10), but they were rarely tailored to NHRs’ needs and their effectiveness remains questionable.Conclusion:Multidimensional opportunities to promote PA in NHRs are identified.
Validity of the Multidimensional Outcome Expectations for Exercise Scale in Continuing-Care Retirement Communities
Authors: Hall Katherine S. , Wójcicki Thomas R. , Phillips Siobhan M. , McAuley Edward 
Published: August 2016

Objective:The current study examined the psychometric properties and validity of the Multidimensional Outcome Expectations for Exercise Scale (MOEES) in a sample of older adults with physical and functional comorbidities.Methods:Confirmatory factor analysis was used to examine the hypothesized 3-factor model in 108 older adults (M age 85 yr) residing in continuing-care retirement communities.Results:Analyses supported the 3-factor structure of the MOEES reflecting physical, social, and self-evaluative outcome expectations, with a 12-item model providing the best fit. Theorized bivariate associations between outcome expectations and physical activity, self-efficacy, and functional performance were all supported.Conclusions:The 12-item version of the MOEES appears to be a reliable and valid measure of outcome expectations for exercise in this sample of older adults with physical and functional comorbidities. Further examination of the factor structure and the longitudinal properties of this measure in older adults is warranted.