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Grégoire P. Millet and Kilian Jornet

98%, and the subject reported regularly “dizziness symptoms.” The training volumes/contents as well as the duration of NH or HH exposures were calculated from his training diary. The times and uphill velocities were calculated from his GPS online data. Results The details of the activity (running

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Ralph Maddison, Yannan Jiang, Stephen Vander Hoorn, Daniel Exeter, Cliona Ni Mhurchu and Enid Dorey

This study aimed to describe the location and intensity of free-living physical activity in New Zealand adolescents during weekdays and weekend days using Global Positioning Systems (GPS), accelerometry, and Geographical Information Systems (GIS). Participants (n = 79) aged 12–17 years (M = 14.5, SD 1.6) recruited from two large metropolitan high schools each wore a GPS watch and an accelerometer for four consecutive days. GPS and accelerometer data were integrated with GIS software to map the main locations of each participant’s episodes of moderate-vigorous physical activity. On average participants performed 74 (SD 36) minutes of moderate and 7.5 (SD 8) minutes of vigorous activity per day, which on weekdays was most likely to occur within a 1 km radius of their school or 150 meters of their home environment. On weekends physical activity patterns were more disparate and took place outside of the home environment. Example maps were generated to display the location of moderate to vigorous activity for weekdays and weekends.

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César Meylan, Joshua Trewin and Kelly McKean

The aims of the current study were to examine the external validity of inertial-based parameters (inertial movement analysis [IMA]) to detect multiplanar explosive actions during maximal sprinting and change of direction (COD) and to further determine its reliability, set appropriate magnitude bands for match analysis, and assess its variability during international women’s soccer matches. Twenty U20 female soccer players, wearing global positioning system (GPS) units with a built-in accelerometer, completed 3 trials of a 40-m sprint and a 20-m sprint with a change of direction to the right or left at 10 m. Furthermore, 13 women’s national-team players (157 files; 4–27 matches/player) were analyzed to ascertain match-to-match variability. Video synchronization indicated that the IMA signal was instantaneous with explosive movement (acceleration, deceleration, COD). Peak GPS velocity during the 40-m sprint showed similar reliability (coefficient of variation [CV] = 2.1%) to timing gates but increased before and after COD (CV = 4.5–13%). IMA variability was greater at the start of sprints (CV = 16–21%) than before and after COD (CV = 13–16%). IMA threshold for match analysis was set at 2.5 m · s–1 · s–1 by subtracting 1 SD from the mean IMA during sprint trials. IMA match variability (CV = 14%) differed from high-speed GPS metrics (35–60%). Practitioners are advised that timing lights should remain the gold standard for monitoring sprint and acceleration capabilities of athletes. However, IMA could be a reliable method to monitor explosive actions between matches and assess changes due to various factors such as congested schedule, tactics, heat, or altitude.

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Philip J. Troped, Ellen K. Cromley, Maren S. Fragala, Steven J. Melly, Hope H. Hasbrouck, Steven L. Gortmaker and Ross C. Brownson

Background:

To determine how trail characteristics may influence use, reliable and valid audit tools are needed.

Methods:

The Path Environment Audit Tool (PEAT) was developed with design, amenity, and aesthetics/maintenance items. Two observers independently audited 185 trail segments at 6 Massachusetts facilities. GPS-derived items were used as a “gold standard.” Kappa (k) statistics, observed agreement and intraclass correlation coefficients (ICCs) were calculated to assess inter-observer reliability and validity.

Results:

Fifteen of 16 primary amenity items had k-values ≥ 0.49 (“moderate”) and all had observed agreement ≥ 81%. Seven binary design items had k-values ranging from 0.19 to 0.71 and three of 5 ordinal items had ICCs ≥ 0.52. Only two aesthetics/maintenance items (n = 7) had moderate ICCs. Observed agreement between PEAT and GPS items was ≥ 0.77; k-values were ≥ 0.57 for 7 out of 10 comparisons.

Conclusions:

PEAT has acceptable reliability for most of its primary items and appears ready for use by researchers and practitioners.

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Dean Ritchie, Will G. Hopkins, Martin Buchheit, Justin Cordy and Jonathan D. Bartlett

Purpose:

Load monitoring in Australian football (AF) has been widely adopted, yet team-sport periodization strategies are relatively unknown. The authors aimed to quantify training and competition load across a season in an elite AF team, using rating of perceived exertion (RPE) and GPS tracking.

Methods:

Weekly totals for RPE and GPS loads (including accelerometer data; PlayerLoad) were obtained for 44 players across a full season for each training modality and for competition. General linear mixed models compared mean weekly load between 3 preseason and 4 in-season blocks. Effects were assessed with inferences about magnitudes standardized with between-players SD.

Results:

Total RPE load was most likely greater during preseason, where the majority of load was obtained via skills and conditioning. There was a large reduction in RPE load in the last preseason block. During in-season, half the total load came from games and the remaining half from training, predominantly skills and upper-body weights. Total distance, high-intensity running, and PlayerLoad showed large to very large reductions from preseason to in-season, whereas changes in mean speed were trivial across all blocks. All these effects were clear at the 99% level.

Conclusions:

These data provide useful information about targeted periods of loading and unloading across different stages of a season. The study also provides a framework for further investigation of training periodization in AF teams.

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Philip R. Hayes, Kjell van Paridon, Duncan N. French, Kevin Thomas and Dan A. Gordon

Purpose:

The aim of this study was to develop a laboratory-based treadmill simulation of the on-course physiological demands of an 18-hole round of golf and to identify the underlying physiological responses.

Methods:

Eight amateur golfers completed a round of golf during which heart rate (HR), steps taken, and global positioning system (GPS) data were assessed. The GPS data were used to create a simulated discontinuous round on a treadmill. Steps taken and HR were recorded during the simulated round.

Results:

During the on-course round, players covered a mean (±SD) of 8,251 ± 450 m, taking 12,766 ± 1,530 steps. The mean exercise intensity during the on-course round was 31.4 ± 9.3% of age-predicted heart rate reserve (%HRR) or 55.6 ± 4.4% of age-predicted maximum HR (%HRmax). There were no significant differences between the simulated round and the on-course round for %HRR (P = .537) or %HR max (P = .561) over the entire round or for each individual hole. Furthermore, there were no significant differences between the two rounds for steps taken. Typical error values for steps taken, HR, %HRmax, and %HRR were 1,083 steps, ±7.6 b·min-1, ±4.5%, and ±8.1%, respectively.

Conclusion:

Overall, the simulated round of golf successfully recreated the demands of an on-course round. This simulated round could be used as a research tool to assess the extent of fatigue during a round of golf or the impact of various interventions on golfers.

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Samuel Ryan, Aaron J. Coutts, Joel Hocking and Thomas Kempton

Purpose:

To examine the influence of a range of individual player characteristics and match-related factors on activity profiles during professional Australian football matches.

Methods:

Global positioning system (GPS) profiles were collected from 34 professional Australian football players from the same club over 15 competition matches. GPS data were classified into relative total and high-speed running (HSR; >20 km/h) distances. Individual player aerobic fitness was determined from a 2-km time trial conducted during the preseason. Each match was classified according to match location, season phase, recovery length, opposition strength, and match outcome. The total number of stoppages during the match was obtained from a commercial statistics provider. A linear mixed model was constructed to examine the influence of player characteristics and match-related factors on both relative total and HSR outputs.

Results:

Player aerobic fitness had a large effect on relative total and HSR distances. Away matches and matches lost produced only small reductions in relative HSR distances, while the number of rotations also had a small positive effect. Matches won, more player rotations, and playing against strong opposition all resulted in small to moderate increases in relative total distance, while early season phase, increased number of stoppages, and away matches resulted in small to moderate reductions in relative total distance.

Conclusions:

There is a likely interplay of factors that influence running performance during Australian football matches. The results highlight the need to consider a variety of contextual factors when interpreting physical output from matches.

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Sarah Hardcastle and Adrian H. Taylor

There has been increasing interest in promoting health-enhancing exercise in primary-care services. One popular approach in the U.K. has been general practitioner (GP) exercise-referral plans in which mostly sedentary patients are referred by GPs to an exercise program at a local leisure center. It is not clear, however, how older women assimilate such a referral system into cognitive processes associated with physical activity involvement. This interpretivist study adopted unstructured interviewing and life-story technique to embrace subjectivity and contextuality in an attempt to capture the complex processes and to explore both common and diverse experience. The study explored referred older women's accounts of their past and current experiences of physical activity and their perceptions of what blocks or motivates them to be active. Fifteen newly referred older women (50–80 years old) were interviewed at various points during their prescribed 10-week exercise program. The findings highlight the importance of psychosocial dimensions and informal networks in the referral processes.

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Jake Schuster, Dan Howells, Julien Robineau, Anthony Couderc, Alex Natera, Nick Lumley, Tim J. Gabbett and Nick Winkelman

Rugby sevens, a sport new to the Olympics, features high-intensity intermittent running and contact efforts over short match durations, normally 6 times across 2 to 3 d in a tournament format. Elite rugby sevens seasons often include over a dozen competitive tournaments over less than 9 months, demanding deliberate and careful training-stress balance and workload management alongside development of the necessary physical qualities required for competition. Focus on running and repeated power skills, strength, and match-specific conditioning capacities is advised. Partial taper approaches in combination with high-speed running (>5 m/s from GPS measures) before and between tournaments in succession may reduce injury rates and enhance performance. In a sport with substantial long-haul intercontinental travel and repetitive chronic load demands, management of logistics including nutrition and recovery is inclusive of the formula for success in the physical preparation of elite rugby sevens athletes.

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Conor M. Bolger, Jan Kocbach, Ann Magdalen Hegge and Øyvind Sandbakk

Purpose:

To compare the speed and heart-rate profiles during international skating and classical competitions in male and female world-class cross-country skiers.

Methods:

Four male and 5 female skiers performed individual time trials of 15 km (men) and 10 km (women) in the skating and classical techniques on 2 consecutive days. Races were performed on the same 5-km course. The course was mapped with GPS and a barometer to provide a valid course and elevation profile. Time, speed, and heart rate were determined for uphill, flat, and downhill terrains throughout the entire competition by wearing a GPS and a heart-rate monitor.

Results:

Times in uphill, flat, and downhill terrain were ~55%, 15–20%, and 25–30%, respectively, of the total race time for both techniques and genders. The average speed differences between skating and classical skiing were 9% and 11% for men and women, respectively, and these values were 12% and 15% for uphill, 8% and 13% for flat (all P < .05), and 2% and 1% for downhill terrain. The average speeds for men were 9% and 11% faster than for women in skating and classical, respectively, with corresponding numbers of 11% and 14% for uphill, 6% and 11% for flat, and 4% and 5% for downhill terrain (all P < .05). Heart-rate profiles were relatively independent of technique and gender.

Conclusions:

The greatest performance differences between the skating and classical techniques and between the 2 genders were found on uphill terrain. Therefore, these speed differences could not be explained by variations in exercise intensity.