Outdoor Activity during Class Recess Reduces Myopia Onset and Progression in School Children

The myopia boom

“…After one year, doctors had diagnosed myopia in 8% of the children, compared with 18% at a nearby school 12 .…”

The Influence of Light Exposure and Seasonal Changes on Short-Term and Longer-Term Changes in Axial Length of the Human Eye

“…The relatively consistent findings from studies of a range of pediatric populations across different geographic locations, demonstrating an association between more outdoor activity and less prevalence (Parssinen & Lyyra, 1993;Mutti et al, 2002;Onal et al, 2007;Rose et al, 2008a;Rose et al, 2008b;Dirani et al, 2009;Deng et al, 2010;Donovan et al, 2012;Fujiwara et al, 2012;Guggenheim et al, 2012;Cui et al, 2013;French et al, 2013cFrench et al, , 2013bGuo et al, 2013a;Wu et al, 2013;Read et al, 2014;He et al, 2015) and incidence (Parssinen & Lyyra, 1993;Jones et al, 2007;Onal et al, 2007;Guggenheim et al, 2012;French et al, 2013cFrench et al, , 2013bWu et al, 2013;He et al, 2015) of myopia support a potential role of light exposure in the development of myopia. Furthermore, the documented seasonal variations in myopia progression/axial 46 Chapter 2: Measurement duration and frequency impact objective light exposure measures elongation (with slower progression found in summer, where the amount of available environmental light is greater compared to winter) (Deng et al, 2010;Donovan et al, 2012;Fujiwara et al, 2012;Cui et al, 2013;Gwiazda et al, 2014) also emphasises the potential importance of ambient light exposure in the regulation of eye growth.…”

“…A recent longitudinal study (4-years follow-up) that investigated the factors associated with myopia development and progression in primary school children in China also revealed that less time spent outdoors and longer time spent indoors was significantly associated with greater ocular axial elongation and myopia progression (Guo et al, 2017). Recent studies have also shown that interventions to increase outdoor time during school hours result in a significant decrease in myopia incidence (Wu et al, 2013;He et al, 2015), suggesting that time spent outdoors protects against the development of myopia. Although most studies have reported significant associations between more outdoor activity and less prevalence and incidence of myopia, a study of rural Chinese school children (mean age 14.6 years) found no association between outdoor activity and myopia progression (Lu et al, 2009).…”

“…Several studies have shown that children who spend more time outdoors are less likely to become myopic (Parssinen & Lyyra, 1993;Mutti et al, 2002;Jones et al, 2007;Rose et al, 2008a;Rose et al, 2008b;Dirani et al, 2009;Jones-Jordan et al, 2011;Guggenheim et al, 2012;French et al, 2013a;French et al, 2013c;Guo et al, 2013a;Wu et al, 2013;Read et al, 2014;He et al, 2015;Li et al, 2015b;Guo et al, 2017) (Table 1.1). Low levels of outdoor activity have been reported in children living in urban Beijing (1 hour/day) (Guo et al, 2013a), Taiwan (0.5 hours/day) and Singapore (0.5 hours/day) (Rose et al, 2008b), and all of these locations are documented to have a high prevalence of myopia in young populations.…”

“…Epidemiological studies have also provided evidence supporting a possible role for ambient light exposure as an additional important environmental risk factor associated with myopia development (Parssinen & Lyyra, 1993;Mutti et al, 2002;Jones et al, 2007;Onal et al, 2007;Rose et al, 2008a;Rose et al, 2008b;Dirani et al, 2009;Deng et al, 2010;Donovan et al, 2012;Fujiwara et al, 2012;Guggenheim et al, 2012;Cui et al, 2013;French et al, 2013cFrench et al, , 2013bGuo et al, 2013a;Wu et al, 2013;Gwiazda et al, 2014;Read et al, 2014;He et al, 2015) and eye growth during childhood. The relatively consistent findings from studies of a range of pediatric populations across different geographic locations, demonstrating an association between more outdoor activity and less prevalence (Parssinen & Lyyra, 1993;Mutti et al, 2002;Onal et al, 2007;Rose et al, 2008a;Rose et al, 2008b;Dirani et al, 2009;Deng et al, 2010;Donovan et al, 2012;Fujiwara et al, 2012;Guggenheim et al, 2012;Cui et al, 2013;French et al, 2013cFrench et al, , 2013bGuo et al, 2013a;Wu et al, 2013;Read et al, 2014;He et al, 2015) and incidence (Parssine...…”