Table 4.

Changes of dioptre of myopic subjects before and after experiment.

Group	Dioptre before experiment (D)	Post-experimental dioptre (D)	P #	P &	P ∮	P £	P §
Outdoor exercise group	−1.44 ± 0.48	−1.79 ± 0.63	0.000**	—	0.483	0.045*	0.006**
Outdoor control group	−1.39 ± 0.53	−1.91 ± 0.54	0.000**	—	—	0.187	0.036*
Indoor exercise group	−1.57 ± 0.56	−2.13 ± 0.59	0.000**	—	—	—	0.414
Indoor control group	−1.59 ± 0.57	−2.26 ± 0.59	0.000**	—	—	—	—

# means comparison of differences within the group, & means comparison with outdoor sports group, ∮means comparison with outdoor control group, £ means comparison with indoor sports group, § means comparison with indoor control group, *means P < 0.05, **means P < 0.01.