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Luke W. Hogarth, Brendan J. Burkett and Mark R. McKean

Purpose:

To examine the neuromuscular and perceptual fatigue responses to consecutive tag football matches played on the same day and determine the relationship between fatigue and match running performance.

Methods:

Neuromuscular and perceptual fatigue responses of 15 national tag football players were assessed before and during the 2014 State of Origin tournament. Global positioning systems (GPS) provided data on players’ match running performance, and a vertical-jump test and subjective questionnaire were used to assess players’ neuromuscular and perceptual fatigue, respectively.

Results:

There were small to moderate reductions in the majority of match-running-performance variables over consecutive matches, including distance (ES = −0.81), high-speed-running (HSR) distance (ES = −0.51), HSR efforts (ES = −0.64), and maximal accelerations (ES = −0.76). Prematch vertical jump was initially below baseline values before the first match (ES = 0.68−0.88). There were no substantial reductions in vertical-jump performance from baseline values over consecutive matches, although there was a small decline from after match 2 to after match 3 (3.3%; ES = −0.45 ± 0.62). There were progressive reductions in perceived well-being scores after matches 1 (ES = −0.38), 2 (ES = −0.70), and 3 (ES = −1.14). There were small to moderate associations between changes in fatigue measures and match running performance.

Conclusions:

Perceptual fatigue accumulates over consecutive tag football matches, although there were only marginal increases in neuromuscular fatigue. However, both neuromuscular and perceptual fatigue measures were found to contribute to reduced match running performance in the final match.

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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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Carl Petersen, David B. Pyne, Marc R. Portus, Stuart Karppinen and Brian Dawson

Purpose:

The time-motion characteristics and the within-athlete variability in movement patterns were quantified for the same male fast bowler playing One Day International (ODI) cricket matches (n = 12).

Methods:

A number of different time motion characteristics were monitored using a portable 5-Hz global positioning system (GPS) unit (Catapult, Melbourne, Australia).

Results:

The bowler’s mean workload per ODI was 8 ± 2 overs (mean ± SD). He covered a total distance of 15.9 ± 2.5 km per game; 12 ± 3% or 1.9 ± 0.2 km was striding (0.8 ± 0.2 km) or sprinting (1.1 ± 0.2 km), whereas 10.9 ± 2.1 km was spent walking. One high-intensity (running, striding, or sprinting) repetition (HIR) occurred every 68 ± 12 s, and the average duration of a HI effort was 2.7 ± 0.1 s. The player also completed 66 ± 11 sprints per game; mean sprint distance was 18 ± 3 m and maximum sprinting speed 8.3 ± 0.9 m·s−1.

Conclusions:

The movement patterns of this fast bowler were a combination of highly intermittent activities of variable intensity on the base of ~16 km per game. This information provides insight for conditioning coaches to determine the physical demands and to adapt the training and recovery processes of ODI fast bowlers.

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Line Anita Bjørkelund Børrestad, Lars Østergaard, Lars Bo Andersen and Elling Bere

Background:

To provide more accurate assessment of commuting behavior and potential health effect, it is important to have accurate methods. Therefore, the current study aimed to a) compare questionnaire reported mode of commuting with objectively measured data from accelerometer and cycle computer, b) compare moderate vigorous physical activity (MVPA) among children cycling vs. walking to school, and c) thus calculate possible underestimated MVPA, when using accelerometers to measure commuter cycling.

Methods:

A total of 78 children, average age 11.4 (SD = 0.5), participated in the study. Physical activity was measured with cycle computers and accelerometers for 4 days. Mode of commuting and demographic information was self-reported in a questionnaire.

Results:

Children who reported to cycle to school spent significantly more time cycling than those who walked to school, 53.6 (SD = ± 33.9) minutes per day vs. 25.5 (SD = ± 24.6) minutes per day (P = .002) (ie, showing that MVPA, measured by accelerometers, underestimated 28.1 minutes per day among children cycling to school vs. those not cycling to school).

Conclusion:

To provide more accurate assessment of active commuting in children and adolescents future studies should incorporate multiple methodologies such as global position systems (GPS), accelerometers, cycle computers, and self-reported measurements.

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Luis Suarez-Arrones, Javier Núñez, Eduardo Sáez de Villareal, Javier Gálvez, Gabriel Suarez-Sanchez and Diego Munguía-Izquierdo

Purpose:

To describe the repeated-high-intensity activity and internal training load of rugby sevens players during international matches and to compare the differences between the 1st and 2nd halves.

Methods:

Twelve international-level male rugby sevens players were monitored during international competitive matches (n = 30 match files) using global positioning system technology and heart-rate monitoring.

Results:

The relative total distance covered by the players throughout the match was 112.1 ± 8.4 m/min. As a percentage of total distance, 35.0% (39.2 ± 9.0 m/min) was covered at medium speed and 17.1% (19.2 ± 6.8 m/min) at high speed. A substantial decrease in the distance covered at >14.0 km/h and >18.0 km/h, the number of accelerations of >2.78 m/s and >4.0 m/s, repeated-sprint sequences interspersed with ≤60 s rest, and repeated-acceleration sequences interspersed with ≤30 s or ≤60 s rest was observed in the 2nd half compared with the 1st half. A substantial increase in the mean heart rate (HR), HRmax, percentage of time at >80% HRmax and at >90% HRmax, and Edwards training load was observed in the 2nd half compared with the 1st half.

Conclusion:

This study provides evidence of a pronounced reduction in high-intensity and repeated-highintensity activities and increases in internal training load in rugby sevens players during the 2nd half of international matches.

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Pradeep Y. Ramulu, Emilie S. Chan, Tara L. Loyd, Luigi Ferrucci and David S. Friedman

Background:

Measuring physical at home and away from home is essential for assessing health and well-being, and could help design interventions to increase physical activity. Here, we describe how physical activity at home and away from home can be quantified by combining information from cellular network–based tracking devices and accelerometers.

Methods:

Thirty-five working adults wore a cellular network–based tracking device and an accelerometer for 6 consecutive days and logged their travel away from home. Performance of the tracking device was determined using the travel log for reference. Tracking device and accelerometer data were merged to compare physical activity at home and away from home.

Results:

The tracking device detected 98.6% of all away-from-home excursions, accurately measured time away from home and demonstrated few prolonged signal drop-out periods. Most physical activity took place away from home on weekdays, but not on weekends. Subjects were more physically active per unit of time while away from home, particularly on weekends.

Conclusions:

Cellular network–based tracking devices represent an alternative to global positioning systems for tracking location, and provide information easily integrated with accelerometers to determine where physical activity takes place. Promoting greater time spent away from home may increase physical activity.

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Melody Oliver, Hannah Badland, Suzanne Mavoa, Mitch J. Duncan and Scott Duncan

Background:

Global positioning systems (GPS), geographic information systems (GIS), and accelerometers are powerful tools to explain activity within a built environment, yet little integration of these tools has taken place. This study aimed to assess the feasibility of combining GPS, GIS, and accelerometry to understand transport-related physical activity (TPA) in adults.

Methods:

Forty adults wore an accelerometer and portable GPS unit over 7 consecutive days and completed a demographics questionnaire and 7-day travel log. Accelerometer and GPS data were extracted for commutes to/from workplace and integrated into a GIS database. GIS maps were generated to visually explore physical activity intensity, GPS speeds and routes traveled.

Results:

GPS, accelerometer, and survey data were collected for 37 participants. Loss of GPS data was substantial due to a range of methodological issues, such as low battery life, signal drop out, and participant noncompliance. Nonetheless, greater travel distances and significantly higher speeds were observed for motorized trips when compared with TPA.

Conclusions:

Pragmatic issues of using GPS monitoring to understand TPA behaviors and methodological recommendations for future research were identified. Although methodologically challenging, the combination of GPS monitoring, accelerometry and GIS technologies holds promise for understanding TPA within the built environment.

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Daniel A. Rodriguez, Gi-Hyoug Cho, John P. Elder, Terry L. Conway, Kelly R. Evenson, Bonnie Ghosh-Dastidar, Elizabeth Shay, Deborah Cohen, Sara Veblen-Mortenson, Julie Pickrell and Leslie Lytle

Background:

Studies that have combined accelerometers and global positioning systems (GPS) to identify walking have done so in carefully controlled conditions. This study tested algorithms for identifying walking trips from accelerometer and GPS data in free-living conditions. The study also assessed the accuracy of the locations where walking occurred compared with what participants reported in a diary.

Methods:

A convenience sample of high school females was recruited (N = 42) in 2007. Participants wore a GPS unit and an accelerometer, and recorded their out-of-school travel for 6 days. Split-sample validation was used to examine agreement in the daily and total number of walking trips with Kappa statistics and count regression models, while agreement in locations visited by walking was examined with geographic information systems.

Results:

Agreement varied based on the parameters of the algorithm, with algorithms exhibiting moderate to substantial agreement with self-reported daily (Kappa = 0.33−0.48) and weekly (Kappa = 0.41−0.64) walking trips. Comparison of reported locations reached by walking and GPS data suggest that reported locations are accurate.

Conclusions:

The use of GPS and accelerometers is promising for assessing the number of walking trips and the walking locations of adolescent females.

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Jason C. Tee, Mike I. Lambert and Yoga Coopoo

Purpose:

In team sports, fatigue is manifested by a self-regulated decrease in movement distance and intensity. There is currently limited information on the effect of fatigue on movement patterns in rugby union match play, particularly for players in different position groups (backs vs forwards). This study investigated the effect of different match periods on movement patterns of professional rugby union players.

Methods:

Global positioning system (GPS) data were collected from 46 professional match participations to determine temporal effects on movement patterns.

Results:

Total relative distance (m/min) was decreased in the 2nd half for both forwards (–13%, ±8%, ES = very likely large) and backs (–9%, ±7%, ES = very likely large). A larger reduction in high-intensity-running distance in the 2nd half was observed for forwards (–27%, ±16%, ES = very likely medium) than for backs (–10%, ±15%; ES = unclear). Similar patterns were observed for sprint (>6 m/s) frequency (forwards –29%, ±29%, ES = likely small vs backs –13% ±18%, ES = possibly small) and acceleration (>2.75 m/s2) frequency (forwards –27%, ±24%, ES = likely medium vs backs –5%, ±46%, ES = unclear). Analysis of 1st- and 2nd-half quartiles revealed differing pacing strategies for forwards and backs. Forwards display a “slow-positive” pacing strategy, while the pacing strategy of backs is “flat.”

Conclusions:

Forwards suffered progressively greater performance decrements over the course of the match, while backs were able to maintain performance intensity. These findings reflect differing physical demands, notably contact and running loads, of players in different positions.

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Jakob Tarp, Lars B. Andersen and Lars Østergaard

Background:

Cycling to and from school is an important source of physical activity (PA) in youth but it is not captured by the dominant objective method to quantify PA. The aim of this study was to quantify the underestimation of objectively assessed PA caused by cycling when using accelerometry.

Methods:

Participants were 20 children aged 11 to 14 years from a randomized controlled trial performed in 2011. Physical activity was assessed by accelerometry with the addition of heart rate monitoring during cycling to school. Global positioning system (GPS) was used to identify periods of cycling to school.

Results:

Mean minutes of moderate-to-vigorous physical activity (MVPA) during round-trip commutes was 10.8 (95% CI: 7.1−16.6). Each kilometer of cycling meant an underestimation of 9314 (95% CI: 7719−11238) counts and 2.7 (95% CI: 2.1−3.5) minutes of MVPA. Adjusting for cycling to school increased estimates of MVPA/day by 6.0 (95% CI: 3.8−9.6) minutes.

Conclusions:

Cycling to and from school contribute substantially to levels of MVPA and to mean counts/min in children. This was not collected by accelerometers. Using distance to school in conjunction with self-reported cycling to school may be a simple tool to improve the methodology.