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. 2015 Apr 1:12:44.
doi: 10.1186/s12966-015-0204-6.

Longitudinal changes in sedentary time and physical activity during adolescence

Sarah K Harding  1 , Angie S Page  2 , Catherine Falconer  3 , Ashley R Cooper  4   5
Affiliations

Longitudinal changes in sedentary time and physical activity during adolescence

Sarah K Harding et al. Int J Behav Nutr Phys Act. .

Abstract

Background: Low levels of physical activity and high time spent in sedentary activities have been associated with unfavourable health outcomes in adolescents. During adolescence, physical activity declines and sedentary time increases, however little is known about whether the magnitude of these changes differs within or between school-time, after-school time, or at weekends.

Methods: Adolescents (n = 363) participating in the PEACH (Personal and Environmental Associations with Children's Health) project provided accelerometer data at 12 and 15 years of age. Data were collected in 2008/2009 and 2012/2013. Time spent sedentary (<100 cpm), in light physical activity (LPA (100-2295 cpm) and in moderate to vigorous physical activity (MVPA: ≥ 2296 cpm) were generated for school-time, after-school time and for weekends using school-specific start and finish times. All data were analysed in 2014.

Results: The proportion of time spent sedentary significantly increased during school (+8.23%, 95% CI = 7.35 to 9.13), after-school (+6.99%, 95% CI = 5.91 to 8.07) and at weekends (+6.86%, 95% CI = 5.10 to 8.62). A parallel decrease was found in the proportion of time spent in LPA during school (-7.62%, 95% CI = -8.26 to -6.98), after-school (-7.01%, 95% CI = -7.74 to -6.28) and at weekends (-6.72%, 95% CI = -7.80 to -5.65). The proportion of time spent in MVPA remained relatively stable during school (-0.64, 95% CI = -1.11 to -0.18), after-school (0.04%, 95% CI = -0.58 to 0.67) and at weekends (-0.14%, 95% CI = -1.18 to 0.90).

Conclusions: Objectively measured sedentary time increased between 12 and 15 years of age during-school, after-school, and at weekends, suggesting that interventions aiming to reduce the age-associated changes in sedentary time are needed in all three time contexts. Future work should identify which sedentary activities change more than others to inform interventions which aim to minimise the increase in time spent sedentary during adolescence.

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References

    1. Janssen I, LeBlanc AG. Review Systematic review of the health benefits of physical activity and fitness in school-aged children and youth. 2010. - PMC - PubMed
    1. Strong WB, Malina RM, Blimkie CJ, Daniels SR, Dishman RK, Gutin B, et al. Evidence based physical activity for school-age youth. J Pediatr. 2005;146:732–7. doi: 10.1016/j.jpeds.2005.01.055. - DOI - PubMed
    1. Craig R, Mindell J, Hirani V. Health survey for England 2008: Volume 1, Physical Activity and fitness. Leeds: The NHS Information Centre for Health and Social Care; 2009.
    1. Ekelund U, Tomkinson G, Armstrong N. What proportion of youth are physically active? Measurement issues, levels and recent time trends. Br J Sports Med. 2011;45:859–65. doi: 10.1136/bjsports-2011-090190. - DOI - PubMed
    1. Mitchell JA, Rodriguez D, Schmitz KH, Audrain McGovern J. Greater screen time is associated with adolescent obesity: a longitudinal study of the BMI distribution from ages 14 to 18. Obesity. 2013;21:572–5. doi: 10.1002/oby.20157. - DOI - PMC - PubMed

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