Table 4.

Grading Recommendations to Assess Development and Evaluation (GRADE) assessment of the evidence of certainty for exercise effects.

Outcomes		Presence of downgrading item of GRADE					Level of certainty of evidence
		Risk of bias	Inconsistency	Indirectness	Imprecision	Publication bias
Chronic exercises	Inhibitory control	Yes	No	No	No	No	II (moderate) (1)
	Working memory	Yes	No	No	Yes	No	III (low) (1) (4)
	Cognitive flexibility	Yes	No	No	Yes	No	III (low) (1) (4)
Acute exercises	Inhibitory control	Yes	No	No	No	No	II (moderate) (1)
	Working memory	Yes	No	No	No	No	II (moderate) (1)
	Cognitive flexibility	Yes	No	No	No	No	II (moderate) (1)

(1) Risk of bias: if the risk of bias of the included studies is present in the meta-analysis, e.g., randomization, concealed allocation, or blinding of assessors/subjects; (2) Inconsistency: point estimates are concentrated, confidence intervals can overlap, and the results of the heterogeneity tests are not statistically significant; (3) Indirectness: present if the intervention studied in the meta-analysis is not directly relevant to the outcome; (4) Imprecision: present if the sum of sample sizes of all individual studies included in the meta-analysis is less than 500, and if the effect size's 95% Cl is comparatively large; (5) Publication bias: present if the author only searched the Chinese database, or only one database.