Correlation and pathways of behavioral activation systems mediating physical activity level and depressive symptoms among college students

Table 1 Differences in physical activity and behavioral activation system in college students with different depressive symptom scores

Variables	Whole (442)	Levels of depressive symptoms			F-value	P value	Post hoc multiple comparisons
		Severe (n = 58)	Moderate (n = 190)	Mild (n = 194)			Severe vs Moderate	Severe vs Mild	Moderate vs Mild
Physical activity (MET-min/week)	1308 ± 954	944 ± 617	1333 ± 1003	1392 ± 967	5.149	0.006	0.006	0.002	0.535
Reward responsiveness	11.88 ± 2.033	11.03 ± 2.232	11.81 ± 2.043	12.21 ± 1.885	7.865	< 0.001	< 0.001	0.010	0.053
Drive	11.22 ± 2.064	10.71 ± 2.656	11.15 ± 2.008	11.45 ± 1.888	3.129	0.045	0.154	0.016	0.152
Fun-seeking	14.17 ± 2.270	13.78 ± 2.968	14.10 ± 2.217	14.36 ± 2.067	1.654	0.192	0.341	0.085	0.260

Table 2 Regression analysis of each variable

Independent variables	B	95%CI		Beta	Coefficient significance test		SE	Collinearity diagnostics
		Lower limit	Upper limit		t-value	P value		Tolerance	VIF
Reward responsiveness	-0.176	-0.268	-0.084	-0.176	-3.766	< 0.001a	0.047	0.980	1.020
Physical activity	-0.116	-0.242	-0.058	-0.116	-3.217	0.001	0.047	0.980	1.020

^aP < 0.001.

Model summary: F = 14.259^a; R = 0.247; R² = 0.061; Adjusted R² = 0.057. VIF: Variance inflation factor; 95%CI: 95% confidence interval.

Table 3 List of the intermediary effect coefficients

Types of effects	B	SE	Bias-corrected 95%CI
			Lower limit	Upper limit	P value
Mediating effect of reward responsiveness	-0.025	0.011	-0.051	-0.008	0.001
Path coefficient of physical activity on drive	0.124	0.045	0.034	0.211	0.007
Direct effect	-0.150	0.041	-0.233	-0.073	< 0.001
Total effect	-0.175	0.040	-0.260	-0.099	< 0.001

95%CI: 95% confidence interval.