bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physiological Measures Tracking Seasonal Changes in Peak Running Speed
Authors: Saunders Philo U. , Cox Amanda J. , Hopkins Will G. , Pyne David B. 
Published: August 2016

It is unclear whether physiological measures monitored in an incremental treadmill test during a training season provide useful diagnostic information about changes in distance running performance.Purpose:To quantify the relationship between changes in physiological measures and performance (peak running speed) over a training season.Methods:Well-trained distance runners (34 males; VO2max 64 ± 6 mL⋅kg-1⋅min-1, mean ± SD) completed four incremental treadmill tests over 17 wk. The tests provided values of peak running speed, VO2max, running economy, and lactate threshold (as speed and %VO2max). The physiological measures were included in simple and multiple linear regression models to quantify the relationship between changes in these measures and changes in peak speed.Results:The typical within-subject variation in peak speed from test to test was 2.5%, whereas those for physiological measures were VO2max (mL⋅min-1⋅kg-1) 3.0%, economy (m⋅kg⋅mL–1) 3.6%, lactate threshold (%VO2max) 8.7%, and body mass 1.8%. In simple models these typical changes predicted the following changes in performance: VO2max 1.4%, economy 0.8%, lactate threshold –0.3%, and body mass –0.2% (90% confidence limits ~±0.7%); the corresponding correlations with performance were 0.57, 0.33, –0.05, and –0.13 respectively (~±0.20). In a multiple linear regression model, the contribution of each physiological variable to performance changed little after adjustment for the other variables.Conclusion:Change in VO2max in an incremental test during a running season is a good predictor of change in peak running speed, change in running economy is a moderate predictor, and lactate threshold and body mass provide little additional information.
Lactate Profile Changes in Relation to Training Characteristics in Junior Elite Cyclists
Authors: Guellich Arne , Seiler Stephen 
Published: August 2016

Purpose:To compare the intensity distribution during cycling training among elite track cyclists who improved or decreased in ergometer power at 4 mM blood lactate during a 15 wk training period.Methods:51 young male German cyclists (17.4 ± 0.5 y; 30 international, 21 national junior finalists) performed cycle ergometer testing at the onset and at the end of a 15 wk basic preparation period, and reported their daily volumes of defined exercise types and intensity categories. Training organization was compared between two subgroups who improved (Responders, n = 17; ΔPLa4⋅kg-1 = +11 ± 4%) or who decreased in ergometer performance (Non-Responders, n = 17; ΔPLa4⋅kg-1 = –7 ± 6%).Results:Responders and Non-Responders did not differ significantly in the time invested in noncycling specific training or in the total cycling distance performed. They did differ in their cycling intensity distribution. Responders accumulated significantly more distance at low intensity (<2 mM blood lactate) while Non-Responders performed more training at near threshold intensity (3–6 mM). Cycling intensity distribution accounted for approx. 60% of the variance of changes in ergometer performance over time. Performance at t1 combined with workout intensity distribution explained over 70% of performance variance at t2.Conclusion:Variation in lactate profle development is explained to a substantial degree by variation in training intensity distribution in elite cyclists. Training at <2 mM blood lactate appears to play an important role in improving the power output to blood lactate relationship. Excessive training near threshold intensity (3–6 mM blood lactate) may negatively impact lactate threshold development. Further research is required to explain the underlying adaptation mechanisms.
The Validity and Reliability of GPS Units for Measuring Distance in Team Sport Specific Running Patterns
Authors: Jennings Denise , Cormack Stuart , Coutts Aaron J. , Boyd Luke , Aughey Robert J. 
Published: August 2016

Purpose:To assess the validity and reliability of distance data measured by global positioning system (GPS) units sampling at 1 and 5 Hz during movement patterns common to team sports.Methods:Twenty elite Australian Football players each wearing two GPS devices (MinimaxX, Catapult, Australia) completed straight line movements (10, 20, 40 m) at various speeds (walk, jog, stride, sprint), changes of direction (COD) courses of two different frequencies (gradual and tight), and a team sport running simulation circuit. Position and speed data were collected by the GPS devices at 1 and 5 Hz. Distance validity was assessed using the standard error of the estimate (±90% confidence intervals [CI]). Reliability was estimated using typical error (TE) ± 90% CI (expressed as coefficient of variation [CV]).Results:Measurement accuracy decreased as speed of locomotion increased in both straight line and the COD courses. Difference between criterion and GPS measured distance ranged from 9.0% to 32.4%. A higher sampling rate improved validity regardless of distance and locomotion in the straight line, COD and simulated running circuit trials. The reliability improved as distance traveled increased but decreased as speed increased. Total distance over the simulated running circuit exhibited the lowest variation (CV 3.6%) while sprinting over 10 m demonstrated the highest (CV 77.2% at 1 Hz).Conclusion:Current GPS systems maybe limited for assessment of short, high speed straight line running and efforts involving change of direction. An increased sample rate improves validity and reliability of GPS devices.
Anthropometric Profiling of Elite Junior and Senior Australian Football Players
Authors: Veale James P. , Pearce Alan J. , Buttifant David , Carlson John S. 
Published: August 2016

Purpose:Body structure and physical development must be addressed when preparing junior athletes for their first season in a senior competition. The aim of this preliminary study was to measure the extent of the assumption that final year junior Australian Football (AF) athletes are at a physical mismatch to their senior counterparts.Methods:Twenty-one male participants (17.71 ± 0.27 y) were recruited from one state based elite junior AF competition and forty-one male participants (22.80 ± 4.24 y) were recruited from one club competing in the senior elite Australian Football League (AFL), who were subsequently divided into two groups; professional rookies aged 18-20 y (19.44 ± 0.70 y; n = 18) and professional seniors aged 21+ y (25.43 ± 3.98 y; n = 23). Dual energy X-ray absorptiometry (DEXA) scans of all participants were completed.Results:Despite being an average 6.0% and 6.1% lighter in total weight and lean mass respectively, no significant difference was found between the elite junior athletes and their professional AFL rookie counterparts. However, significant differences were demonstrated in comparison with the professional AFL senior athletes (P < .01). Both professional AFL groups demonstrated greater than 0.3 kg total bone mineral content (BMC) than the elite junior athletes (P < .01) and significantly greater segmental BMC and bone mineral density (BMD) results (P < .05).Conclusion:While the results identify the differences in body composition of the elite junior athletes, development in a linear fashion is noted, providing useful information for the creation of age appropriate expectations and training programs.
Reduction in Physical Match Performance at the Start of the Second Half in Elite Soccer
Authors: Weston Matthew , Batterham Alan M. , Castagna Carlo , Portas Matthew D. , Barnes Christopher , Harley Jamie , Lovell Ric J. 
Published: August 2016

Purpose:Soccer referees’ physical match performances at the start of the second half (46–60 min) were evaluated in relation to both the corresponding phase of the first half (0–15 min) and players’ performances during the same match periods.Methods:Match analysis data were collected (Prozone, UK) from 12 soccer referees on 152 English Premier League matches during the 2008/09 soccer season. Physical match performance categories for referees and players were total distance, high-speed running distance (speed >5.5 m/s), and sprinting distance (>7.0 m/s). The referees’ heart rate was recorded from the start of their warm-up to the end of the match. The referees’ average distances (in meters) from the ball and fouls were also calculated.Results:No substantial differences were observed in duration (16:42 ± 2:35 vs 16:27 ± 1:00 min) or intensity (107 ± 11 vs 106 ± 14 beats/min) of the referees’ preparation periods immediately before each half. Physical match performance was reduced during the initial phase of the second half when compared with the first half in both referees (effect sizes—standardized mean differences—0.19 to 0.73) and players (effect sizes 0.20 to 1.01). The degree of the decreased performance was consistent between referees and players for total distance (4.7 m), high-speed running (1.5 m), and sprinting (1.1 m). The referees were closer to the ball (effect size 0.52) during the opening phase the second half.Conclusion:Given the similarity in the referees’ preparation periods, it may be that the reduced physical match performances observed in soccer referees during the opening stages of the second half are a consequence of a slower tempo of play.
Relationships Between Triathlon Performance and Pacing Strategy During the Run in an International Competition
Authors: Meur Yann Le , Bernard Thierry , Dorel Sylvain , Abbiss Chris R. , Honnorat Gérard , Brisswalter Jeanick , Hausswirth Christophe 
Published: August 2016

Purpose:The purpose of the present study was to examine relationships between athlete’s pacing strategies and running performance during an international triathlon competition.Methods:Running split times for each of the 107 finishers of the 2009 European Triathlon Championships (42 females and 65 males) were determined with the use of a digital synchronized video analysis system. Five cameras were placed at various positions of the running circuit (4 laps of 2.42 km). Running speed and an index of running speed variability (IRSVrace) were subsequently calculated over each section or running split.Results:Mean running speed over the frst 1272 m of lap 1 was 0.76 km-h–1 (+4.4%) and 1.00 km-h–1 (+5.6%) faster than the mean running speed over the same section during the three last laps, for females and males, respectively (P < .001). A significant inverse correlation was observed between RSrace and IRSVrace for all triathletes (females r = -0.41, P = .009; males r = -0.65, P = .002; and whole population -0.76, P = .001). Females demonstrated higher IRSVrace compared with men (6.1 ± 0.5 km-h–1 and 4.0 ± 1.4 km-h–1, for females and males, respectively, P = .001) due to greater decrease in running speed over uphill sections.Conclusions:Pacing during the run appears to play a key role in high-level triathlon performance. Elite triathletes should reduce their initial running speed during international competitions, even if high levels of motivation and direct opponents lead them to adopt an aggressive strategy.
The Activity Profile in International Taekwondo Competition Is Modulated by Weight Category
Authors: Bridge Craig A. , Jones Michelle A. , Drust Barry 
Published: August 2016

Purpose:To examine the activity profiles of elite male competitors during international Taekwondo competition in relation to fn, feather, and heavy weight categories.Methods:Twelve male Taekwondo competitors equally representing fn, feather, and heavy weight divisions were studied during the 2005 World Taekwondo Championships using a time-motion system developed to analyze the activities and activity phases. The frequency and duration of activities were recorded and assimilated into four independent activity phases: fighting activity, preparatory activity, nonpreparatory activity and stoppage activity. The total number of exchanges and kicks were also calculated for each combat.Results:For all weight groupings the mean ± SD fighting time was 1.7 ± 0.3 s, preparatory time 6.4 ± 2.1 s, nonpreparatory time 3.0 ± 0.6 s, referee stoppage time 2.8 ± 0.9 s and 28 ± 6 exchanges and 31 ± 7 kicks were performed. Differences in the mean fighting time (fn: 1.4 ± 0.2 s vs heavy: 1.8 ± 0.3 s; P = .03; effect size [ES] = 1.57), preparatory time (fn: 5.3 ± 1.0 s vs feather: 8.2 ± 2.6 s; P = .03; ES = 1.47) and the total number of exchanges (feather: 24 ± 6 vs heavy: 32 ± 5; P = .03; ES = 1.44) were identified between the weight categories.Conclusion:The activity profile in international Taekwondo competition was modulated by competitors’ weight category. These findings suggest that conditioning sessions may need to be specialized to the requirements of specific weight categories.
Increased High-Intensity Activity in Elite Australian Football Finals Matches
Authors: Aughey Robert J. 
Published: August 2016

Background:Australian football (AF) is a highly intermittent sport, requiring athletes to accelerate hundreds of times with repeated bouts of high-intensity running (HIR). Players aim to be in peak physical condition for finals, with anecdotal evidence of increased speed and pressure of these games.Purpose:However, no data exists on the running demands of finals games, and therefore the aim of this study was to compare the running demands of finals to regular season games with matched players and opponents.Methods:Player movement was recorded by GPS at 5 Hz and expressed per period of the match (rotation), for total distance, high-intensity running (HIR, 4.17-10.00 m·s-1) and maximal accelerations (2.78-10.00 m·s–2). All data was compared for regular season and finals games and the magnitude of effects was analyzed with the effect size (ES) statistic and expressed with confidence intervals.Results:Each of the total distance (11%; ES: 0.78 ± 0.30), high-intensity running distance (9%; ES: 0.29 ± 0.25) and number of maximal accelerations (97%; ES: 1.30 ± 0.20) increased in finals games. The largest percentage increases in maximal accelerations occurred from a commencement velocity of between 3–4 (47%; ES: 0.56 ± 0.21) and 4–5 m·s-1 (51%; ES: 0.72 ± 0.26), and with <19 s between accelerations (53%; ES: 0.63 ± 0.27).Conclusion:Elite AF players nearly double the number of maximal accelerations in finals compared with regular season games. This large increase is superimposed on requirements to cover a greater total distance and spend more time at high velocity during finals games. Players can be effectively conditioned to cope with these increased demands, even during a long competitive season.
The Effect of Cluster Loading on Force, Velocity, and Power During Ballistic Jump Squat Training
Authors: Hansen Keir T. , Cronin John B. , Newton Michael J. 
Published: August 2016

Purpose:The purpose of this study was to investigate the effect of set structure, in terms of repetition workrest ratios on force, velocity, and power during jump squat training.Methods:Twenty professional and semiprofessional rugby players performed training sessions comprising four sets of 6 repetitions of a jump squat using four different set configurations. The first involved a traditional configuration (TR) of 4 × 6 repetitions with 3 min of rest between sets, the second (C1) 4 × 6 × singles (1 repetition) with 12 s of rest between repetitions, the third (C2) 4x3 × doubles (2 repetitions) with 30 s of rest between pairs, and the third (C3) 4 × 2 × triples (3 repetitions) with 60 s of rest between triples. A spreadsheet for the analysis of controlled trials that calculated the P-value, and percent difference and Cohen’s effect size from log-transformed data was used to investigate differences in repetition force, velocity, and power profiles among configurations.Results:Peak power was significantly lower (P < .05) for the TR condition when compared with C1 and C3 for repetition 4, and all cluster configurations for repetitions 5 and 6. Peak velocity was significantly lower (P < .05) for the TR condition compared with C3 at repetition 4, significantly lower compared with C2 and C3 at repetition 5, and significantly lower compared with all cluster conditions for repetition 6.Conclusions:Providing inter-repetition rest during a traditional set of six repetitions can attenuate decreases in power and velocity of movement through the set.
Validity of a Reactive Agility Test for Australian Football
Authors: Henry Greg , Dawson Brian , Lay Brendan , Young Warren 
Published: August 2016

Purpose:To study the validity of a video-based reactive agility test in Australian footballers.Methods:15 higher performance, 15 lower performance, and 12 nonfootballers completed a light-based reactive agility test (LRAT), a video-based reactive agility test (VRAT), and a planned test (PLAN).Results:With skill groups pooled, agility time in PLAN (1346 ± 66 ms) was significantly faster (P = .001) than both reactive tests (VRAT = 1550 ± 102 ms; LRAT = 1572 ± 97 ms). In addition, decision time was significantly faster (P = .001; d = 0.8) in LRAT (278 ± 36 ms) than VRAT (311 ± 47 ms). The correlation in agility time between the two reactive tests (r = .75) was higher than between the planned and reactive tests (r = .41–.68). Higher performance players had faster agility and movement times on VRAT (agility, 130 ± 24 ms, d = 1.27, P = .004; movement, 69 ± 73 ms, d = 0.88, P = .1) and LRAT (agility, 95 ± 86 ms, d = 0.99, P = .08; movement, 79 ± 74 ms; d = 0.9; P = .08) than the nonfootballers. In addition, higher (55 ± 39 ms, d = 0.87, P = .05) and lower (40 ± 57 ms, d = 0.74, P = .18) performance groups exhibited somewhat faster agility time than nonfootballers on PLAN. Furthermore, higher performance players were somewhat faster than lower performance for agility time on the VRAT (63 ± 85 ms, d = 0.82, P = .16) and decision time on the LRAT (20 ± 39 ms, d = 0.66, P = .21), but there was little difference in PLAN agility time between these groups (15 ± 150 ms, d = 0.24, P = .8).Conclusions:Differences in decision-making speed indicate that the sport-specific nature of the VRAT is not duplicated by a light-based stimulus. In addition, the VRAT is somewhat better able to discriminate different groups of Australian footballers than the LRAT. Collectively, this indicates that a video-based test is a more valid assessment tool for examining agility in Australian footballers.
Comparison of Physiological Responses and Performance Between Mountain Bicycles With Differing Suspension Systems
Authors: Herrick Jeffrey E. , Flohr Judith A. , Wenos Davis L. , Saunders Michael J. 
Published: August 2016

Purpose:This study compared the metabolic and performance effects of riding front-only suspension (FS) and front-and-rear suspension (FRS) mountain bicycles on an off-road course that simulated competitive cross-country race conditions (>105 min in duration, with ∼70% of time spent riding uphill).Methods:Seven competitive mountain bikers (73.8 ± 7.6 kg; 61.0 ± 4.3 mL·kg–1·min–1) completed two randomized FS and FRS trials. Bikes were similar, excluding rear wheel suspension on the FRS, which increased bike weight by ∼2 kg. Each trial consisted of four laps of rugged 8 km trail with 154 m of elevation gain per lap. The first three laps were performed at ∼70% of VO2max; VO2, HR, and RPE were collected during the first and third laps. The final lap was performed as a maximal time-trial effort.Results:During the first and third laps, VO2, HR, and RPE were similar between FS and FRS. However, FS was significantly faster than FRS during the ascending segment of the course (17.6 ± 2.9 vs 18.9 ± 3.4 min,P= .035), despite similar VO2(P= .651). Although not statistically significant, FRS tended to be faster than FS during the descending portion of the course (8.1 ± 2.0 vs 9.1 ± 2.1,P= .067) at similar VO2. Performance during the final time-trial lap was significantly faster for FS than FRS (24.9 ± 3.9 min, 27.5 ± 4.9 min,P= .008).Conclusion:FS was faster than FRS over a course that simulated competitive cross-country race conditions. The faster times were likely the result of improved cycling economy during ascending, which were at least partially influenced by the lighter weight of the FS.
Resistance Exercise Inter-Set Cooling Strategy: Effect on Performance and Muscle Damage
Authors: Galoza Pedro , Sampaio-Jorge Felipe , Machado Marco , Fonseca Ricardo , Silva Pierre A. V. 
Published: August 2016

Purpose:To compare the effect of inter-set cooling and no cooling during resistance exercise (RE) on the total repetitions and select muscle damage biomarker responses.Methods:Sixteen healthy men volunteered to participate in this study and were randomly assigned to Cooling (n = 8) or Control (n = 8) groups. They performed a RE protocol consisting of four sets of biceps curl at 80% of 1RM. The cooling group received the application of wet bags of ice during each inter-set rest interval (Cooling), while the Control realized the same protocol without ice application. Exercise was performed to voluntary fatigue and the numbers of repetitions per set were recorded. Subjects provided blood samples before and at 24, 48, and 72 h following RE to evaluate serum CK activity and myoglobin concentration.Results:The Cooling group produced a greater number of repetitions (approx. 21%) than did the Control, but there were no differences in serum CK activity and myoglobin responses between the groups.Conclusion:Incorporating inter-set external cooling augments the number of repetitions per set during RE without inducing an additional muscle damage biomarker response.
Effect of Daily Cold Water Immersion on Heart Rate Variability and Subjective Ratings of Well-Being in Highly Trained Swimmers
Authors: Haddad Hani Al , Parouty Jonathan , Buchheit Martin 
Published: August 2016

Purpose:We investigated the effect of daily cold water immersion (CWI), during a typical training week, on parasympathetic activity and subjective ratings of well-being.Methods:Over two different weeks, eight highly trained swimmers (4 men; 19.6 ± 3.2 y) performed their usual training load (5 d/wk, approx. 21 h/wk). Last training session of each training day was immediately followed by 5 min of seated recovery, in randomized order, with CWI (15°C) or without (CON). Each morning before the first training session (6:30 AM) during the two experimental weeks, subjective ratings of well-being (eg, quality of sleep) were assessed and the R-R intervals were recorded for 5 min in supine position. A vagal-related index (ie, natural logarithm of the square root of the mean of the sum of the squares of differences between adjacent normal R-R intervals; Ln rMSSD) was calculated from the last 3-min segment.Results:Compared with CON, CWI effect on Ln rMSSD was rated as possibly beneficial on day 2 [7.0% (–3; 19)], likely beneficial on day 3 [20.0% (1.5; 43.5)], very likely beneficial on day 4 [30.4% (12.2; 51.6)] and likely beneficial on day 5 [24.1% (–0.4; 54.8)]. Cold water immersion was associated with a likely greater quality of sleep on day 2 [30.0% (2.7; 64.6)], very likely on day 3 [31.0% (5.0; 63.1)] and likely on day 4 [38.6% (11.4; 72.4)] when compared with CON.Conclusion:Five minutes of CWI following training can reduce the usual exercise-induced decrease in parasympathetic activity and is associated with improved rating of perceived sleep quality.