The characteristics of both groups are presented in Table 2. The statistical analysis (t-/χ2 test) showed no significant differences (p > 0.05) between the groups at baseline with regard to personal data and the mean values of the measurement instruments (Table 2). With regard to average energy consumption, this was 6.19 (± 2.1) kcal/kg and week in the combined physical activity training group and 11.67 (± 2.7) kcal/kg and week in the aerobic activity training group; this difference was statistically significant (t (60) = −9.019, p < 0.001). The pre- and posttreatment scores of all questionnaires are presented in Table 3.

Table 2 Descriptive group characteristics for the combined physical activity training (CPAT) group and the aerobic activity training (AAT) groupTable 3 Outcome measures for the combined physical activity training (CPAT) group and the aerobic activity training (AAT) group before (t1) and after (t2) treatment Beck Depression Inventory (BDI II; [18])

Decreasing scores from t1 to t2 indicate a lower level of self-reported depressive symptoms after the intervention in both groups. The within-group effect sizes were d = 0.49 for the combined physical activity training group and d = 0.80 for the aerobic activity training group. ANOVA indicated that the main effect of “time” was significant (F (1, 60) = 51.91; p = 0.000) but not the “group” (F (1, 60) = 1.74; p = 0.192) or the interaction of “time × group” (F (1, 60) = 2.84; p = 0.097).

Symptom Checklist (SCL-K-9; [19])

Decreasing scores from t1 to t2 indicate a lower level of global severity after the intervention in both groups. The within-group effect sizes were d = 0.41 for the combined physical activity training group and d = 0.35 for the aerobic activity training group. ANOVA indicated that the main effect of “time” was significant (F (1, 60) = 15.42; p = 0.000) but not the “group” (F (1, 60) = 2.18; p = 0.145) or the interaction of “time × group” (F (1, 60) = 0.011; p = 0.918).

Body Image Questionnaire (QBI-20; [20])

Decreasing scores from t1 to t2 indicate a lower level of negative body image (QBI-20-NBI) after the intervention in both groups. ANOVA indicated that the main effect of “time” was not significant (F (1, 60) = 2.03; p = 0.160), nor was the “group” (F (1, 60) = 0.164; p = 0.687) or the interaction of “time × group” (F (1, 60) = 0.178; p = 0.675).

Regarding the vital body dynamic (QBI-20-VBD), increasing scores from t1 to t2 indicate a higher level after the intervention in both groups. ANOVA indicated that the main effect of “time” was not significant (F (1, 60) = 2.76; p = 0.102) or “group” (F (1, 60) = 3.77; p = 0.057), but the interaction of “time × group” was (F (1, 60) = 4.03; p = 0.049), i.e., the factor “time” was mediated by the factor “group”. A post hoc t-test for dependent samples was significant between t1 and t2 for the aerobic activity training group (t (60) = −2.61; p = 0.014) but not for the combined physical activity training group (t (60) = 0.244; p = 0.809). A post hoc t-test of the mean value differences for the two groups between t1 and t2 was significant (t (60) = 2.01, p = 0.049). Nevertheless, effect sizes were negligible for the combined physical activity training group (d = −0.04) and small for the aerobic activity training group (d = 0.37).

Social Activity Self-Assessment Scale (SASS; [21])

Increasing scores from t1 to t2 indicate a higher level of social function after the intervention in both groups. The within-group effect sizes were d = 0.1 for the combined physical activity training group and d = 0.35 for the aerobic activity training group. ANOVA indicated that the main effect of “time” was significant (F (1, 60) = 8.28; p = 0.006) but not the “group” (F (1, 60) = 0.144; p = 0.705) or the interaction of “time × group” (F (1, 60) = 2.07; p = 0.155).

Multidimensional Self-Esteem Scale (MSES; [22])

Increasing scores from t1 to t2 indicate a higher level of general self-esteem after the intervention in both groups. The within-group effect sizes were d = 0.23 for the combined physical activity training group and d = 0.51 for the aerobic activity training group. ANOVA indicated that the main effect of “time” was significant (F (1, 60) = 23.82; p = 0.000) but not the “group” (F (1, 60) = 0.007; p = 0.936) or the interaction of “time × group” (F (1, 60) = 3.39; p = 0.070).

Regarding the body self-esteem scale, increasing scores from t1 to t2 indicate a higher level after the intervention in both groups. The within-group effect sizes were d = 0.25 for the combined physical activity training group and d = 0.37 for the aerobic physical activity training group. ANOVA indicated that the main effect of “time” was significant (F (1, 60) = 18.10; p = 0.000) but not the “group” (F (1, 60) = 0.003; p = 0.955) or the interaction of “time × group” (F (1, 60) = 1.01; p = 0.317).

Subjective Evaluation of Mental Performance (Flei; [23])

Decreased scores from t1 to t2 on the Flei‑A scale indicate higher attention after the intervention in both groups. ANOVA indicated that the main effect of “time” was not significant (F (1, 60) = 8.60; p = 0.135), nor was the “group” (F (1, 60) = 0.001; p = 0.601) or the interaction of “time × group” (F (1, 60) = 0.720; p = 0.749).

Decreased scores from t1 to t1 on the Flei‑M scale indicate a higher memory score after the intervention in both groups. ANOVA indicated that the main effect of “time” was not significant (F (1, 60) = 13.36; p = 0.193), nor was the “group” (F (1, 60) = 14.44; p = 0.876) or the interaction of “time × group” (F (1, 60)= 2.18; p = 0.331).

Decreased scores from t1 to t1 on the Flei‑E scale indicate a higher executive function after the intervention in both groups. ANOVA indicated that the main effect of “time” was significant (F (1, 60) = 13.10; p = 0.032) but not the “group” (F (1, 60) = 144.24; p = 0.826) or the interaction of “time × group” (F (1, 60)= 1.17; p = 0.764). Low effect sizes in both groups suggest that mental performance is only marginally influenced by the interventions.