a significant trendP = 0.005
A similar positive association was identified between increasing quartile of time spent in total PA and thicker mGCIPL: participants in the second highest and highest quartile (i.e., quartiles 3 and 4) showed thicker mGCIPL by +0.18 μm ( P = 0.016) and +0.16 μm ( P = 0.029), respectively, compared with those in the lowest quartile, with a significant trend ( P = 0.005 for trend).