[Retracted] Physical Exercise Improves Academic Performance: Based on CNKI Meta-Analysis Evidence

Table 3

Differences in the effects of different exercise intensities on student academic performance.

Exercise intensity level (%)	Number of effects	Effect level (SMD)	95% confidence interval		Z	Effect size significance	Differences between groups
			Superior limit	Lower limit
30	4	−0.21	−0.41	−0.02	2.12
40	7	0.03	−0.13	0.19	0.33
50	23	0.16	0.02	0.30	2.29
60	28	0.21	0.08	0.33	3.15
70	5	0.36	0.18	0.54	3.94
80	5	0.40	0.22	0.57	4.37