Wearable activity trackers, devices that measure physical activity under free-living conditions, are part of a rapidly growing trend in medicine. In 2016, Fitbit Inc. was reported to have a 79% market share in wearable activity trackers ( The NPD Group, 2016 ) and shipped 22.5 million units
David R. Bassett, Patty S. Freedson and Dinesh John
Pedro Paulo Deprá, Avelino Amado and Richard E.A. van Emmerik
Many activities of daily living require the integration between postural control and other movements of the body, such as manual movements or tracking visual objects in the environment with the head and eyes. Perceptual information pertaining to the environment coupled with the intrinsic properties
Tyson M. Bain, Georita M. Frierson, Elaine Trudelle-Jackson and James R. Morrow Jr.
Self-report measures have been validated and are widely used. Interest currently lies in the development of simple, valid methods that can be used in any location to determine level of PA in large populations/samples. The purpose of this report is to illustrate tracking of physical activity behaviors and musculoskeletal injury reports on a weekly basis via the Internet.
The Women’s Injury Study (WIN) methodology includes use of BRFSS-related physical activity items that are completed online by more than 900 women weekly for an average of 3 years.
With more than 45,000 weekly physical activity and injury logs, the percentage of total logs submitted via online records is 91%. Self-reported pedometer steps are consistent with similar, smaller research samples.
This report suggests that Internet tracking is a viable means of assessing nearly real-time physical activity, describes the process of developing and monitoring self-reported physical activity behaviors via the Internet, and provides recommendations for others considering such methods.
Johan Cassirame, Hervé Sanchez and Jean-Benoit Morin
Track and field includes competitive events in which conditions are well controlled and regulated by international guidelines so that individual performances could be easily compared. In addition, the rules for competitions are in place to ensure the maximal level of technical and external equity
Carl Petersen, David Pyne, Marc Portus and Brian Dawson
The validity and reliability of three commercial global positioning system (GPS) units (MinimaxX, Catapult, Australia; SPI-10, SPI-Pro, GPSports, Australia) were quantified.
Twenty trials of cricket-specific locomotion patterns and distances (walking 8800 m, jogging 2400 m, running 1200 m, striding 600 m, sprinting 20- to 40-m intervals, and run-a-three) were compared against criterion measures (400-m athletic track, electronic timing). Validity was quantified with the standard error of the estimate (SEE) and reliability estimated using typical error expressed as a coefficient of variation.
The validity (mean ± 90% confidence limits) for locomotion patterns walking to striding ranged from 0.4 ± 0.1 to 3.8 ± 1.4%, whereas for sprinting distances over 20 to 40 m including run-a-three (approx. 50 m) the SEE ranged from 2.6 ± 1.0 to 23.8 ± 8.8%. The reliability (expressed as mean [90% confidence limits]) of estimating distance traveled by walking to striding ranged from 0.3 (0.2 to 0.4) to 2.9% (2.3 to 4.0). Similarly, mean reliability of estimating different sprinting distances over 20 to 40 m ranged from 2.0 (1.6 to 2.8) to 30.0% (23.2 to 43.3).
The accuracy and bias was dependent on the GPS brand employed. Commercially available GPS units have acceptable validity and reliability for estimating longer distances (600–8800 m) in walking to striding, but require further development for shorter cricket-specifc sprinting distances.
Yi-Ching Chen, I-Chen Lin, Yen-Ting Lin, Wei-Min Huang, Chien-Chun Huang and Ing-Shiou Hwang
on perceived errors ( Merchant, Pérez, Zarco, & Gámez, 2013 ; Vanneste, Pouthas, & Wearden, 2001 ). According to the additive accuracy mechanism ( Miall, Weir, & Stein, 1986 ; Pasalar, Roitman, & Ebner, 2005 ), tracking deviations are remedied by superimposition of scaled submovements onto an a
Brendan T. O’ Keeffe, Ciaran MacDonncha, Kwok Ng and Alan E. Donnelly
of the school term in May 2017. To minimize the nonresponse bias, a reinvitation to complete the survey was circulated after 2, 4, and 5 weeks. A unique school identifier code was used to track responses and target initial nonresponders for the reinvitation process. After 5 weeks, all complete
Douglas J. Casa, Samuel N. Cheuvront, Stuart D. Galloway and Susan M. Shirreffs
Seasonal environmental changes can create unique challenges for year-long training among track-and-field athletes. However, the competitive track-and-field season is held in the summer months of the northern hemisphere and major international track-and-field competitions, such as the World
Michelle Hardie Murphy, David Anthony Rowe and Catherine B. Woods
The contribution of sports related factors to predicting long-term physical activity (PA) are unclear. The purpose of this study is to examine tracking of PA during key transition periods in youth and to determine the longitudinal associations between sports club participation and PA.
Participants (n = 873, baseline age 10 to 18 years) completed self-report surveys in 2009 and 2014 that included the PACE+ PA tool and sports club participation questions. Spearman correlations assessed PA tracking. ANCOVA analyses examined predictors (sports participation at baseline) of PA (follow-up), adjusting for (a) age and sex; and (b) age, sex, and baseline PA.
Tracking of PA was weak-to-moderate (ρ = .16 to .47). Greater sports participation frequency at baseline significantly predicted PA at follow-up (P < .01). Involvement in club sports at an elite level had a medium-to-large effect on PA levels 5 years later [d = .75 adjusting for (a); d = .60 adjusting for (b)].
PA should be promoted in youth as tracking coefficients suggest it can, to an extent, continue into later life. The standard achieved in sport has a role in predicting later PA. PA promotion strategies should include frequent, high quality opportunities for sports participation.
Anders Raustorp and Andreas Fröberg
PA through interventions is attributed to the perception that PA is stable and, hence, tracks over time. The concept of tracking refers to the tendency for individuals to maintain their rank or position within a group over time, 4 and data from at least 2 time-points are required to assess stability