): 2353 – 2358 . PubMed ID: 25785930 doi:10.1249/MSS.0000000000000662 10.1249/MSS.0000000000000662 25785930 45. Wolff-Hughes DL , Fitzhugh EC , Bassett DR , Churilla JR . Total activity counts and bouted minutes of moderate-to-vigorous physical activity: relationships with cardiometabolic
Kenneth E. Powell, Abby C. King, David M. Buchner, Wayne W. Campbell, Loretta DiPietro, Kirk I. Erickson, Charles H. Hillman, John M. Jakicic, Kathleen F. Janz, Peter T. Katzmarzyk, William E. Kraus, Richard F. Macko, David X. Marquez, Anne McTiernan, Russell R. Pate, Linda S. Pescatello and Melicia C. Whitt-Glover
Anna Goodman, James Paskins and Roger Mackett
Children in primary school are more physically active in the spring/summer. Little is known about the relative contributions of day length and weather, however, or about the underlying behavioral mediators.
325 British children aged 8 to 11 wore accelerometers as an objective measure of physical activity, measured in terms of mean activity counts. Children simultaneously completed diaries in which we identified episodes of out-of-home play, structured sports, and active travel. Our main exposure measures were day length, temperature, rainfall, cloud cover, and wind speed.
Overall physical activity was higher on long days (≥ 14 hours daylight), but there was no difference between short (< 9.5 hours) and medium days (10.2–12.6 hours). The effect of long day length was largest between 5 PM and 8 PM, and persisted after adjusting for rainfall, cloud cover, and wind. Up to half this effect was explained by a greater duration and intensity of out-of-home play on long days; structured sports and active travel were less affected by day length.
At least above a certain threshold, longer afternoon/evening daylight may have a causal role in increasing child physical activity. This strengthens the public health arguments for daylight saving measures such as those recently under consideration in Britain.
Heidi J. Syväoja, Anna Kankaanpää, Jouni Kallio, Harto Hakonen, Janne Kulmala, Charles H. Hillman, Anu-Katriina Pesonen and Tuija H. Tammelin
requiring balance and agility as well as social aspects of PA, which typically do not accumulate activity counts. Alternatively, accelerometer-based MVPA may illustrate cardiovascular activity with increased heart rate and respiratory frequency over other forms of PA. Accordingly, capturing children’s PA in
Tiago V. Barreira, Stephanie T. Broyles, Catrine Tudor-Locke, Jean-Philippe Chaput, Mikael Fogelholm, Gang Hu, Rebecca Kuriyan, Estelle V. Lambert, Carol A. Maher, José A. Maia, Timothy Olds, Vincent Onywera, Olga L. Sarmiento, Martyn Standage, Mark S. Tremblay, Peter T. Katzmarzyk and for the ISCOLE Research Group
episode time distinct from waking nonwear time, and this was done using a 60-second epoch and published automated algorithms. 18 , 19 After exclusion of the nocturnal sleep episode time, nonwear time was determined as any sequence of at least 20 consecutive minutes of zero activity counts. 20 Once
Amherst Recent studies have used triaxial accelerometer activity counts to distinguish standing time from sitting time. Further research is needed on methods for classifying standing versus sitting using step-based metrics. Sparsely detected steps peppered into strings of 0 steps/min (i.e., zero cadence