RESUMO
BACKGROUND: Sedentary behavior (SB; time spent sitting, as distinct from lack of exercise or physical activity) is associated with depression, yet little is known about the relationship between different types of SB (e.g., mentally-passive versus mentally-active) with depression and potential biological mediators of these associations. METHODS: We used cohort data from the 1958 National Child Development Study (n = 4607; 50.4 % women), conducted in UK, employing the 44 y and 46 y waves as baseline, and the 50 y and 55 y waves as follow-up. Participants reported time spent in TV viewing and watching videos (mentally-passive SB); and, time sitting while doing light activities such as deskwork or driving a car during worktime (mentally-active SB). Depression diagnosis was self-reported during the initial and follow-up waves. Waist circumference, C-reactive protein, and glycated hemoglobin were examined as potential mediators. RESULTS: Mentally-passive SB was associated with incident depression (HR: 1.43; 95%CI: 1.19; 1.71), while there was no association for mentally-active SB. Waist circumference (coefficient: -0.03; 95%CI: -0.05; -0.01; 9.2 %) and C-reactive protein (coefficient: -0.03; 95%CI: -0.04; -0.01; 8.3 %), but not glycated hemoglobin, partly mediated the association for mentally-passive SB. CONCLUSIONS: In the relationship of mentally-passive SB with incident depression, the mediating contributions of waist circumference and C-reactive protein point to possible inflammatory-related mechanisms.
Assuntos
Depressão , Comportamento Sedentário , Criança , Humanos , Feminino , Masculino , Depressão/epidemiologia , Proteína C-Reativa/metabolismo , Exercício Físico , Hemoglobinas GlicadasRESUMO
BACKGROUND: Several tests are available to assess the different components of physical fitness, including cardiorespiratory fitness, muscular strength, and flexibility. However, the reliability and validity of physical fitness tests in people with mental disorders has not been meta-analyzed. AIMS: To examine the reliability, concurrent, and convergent validity of physical fitness tests in people with mental disorders. METHODS: Studies evaluating the reliability, concurrent, and convergent validity of physical fitness tests in people with mental disorders were searched from major databases until January 20, 2020. Random-effects meta-analyses were performed pooling (1) reliability: test-retest correlations at two-time points, (2) convergent validity between submaximal tests and maximal protocols, or (3) concurrent validity between two submaximal tests. Associations are presented using r values and 95% confidence intervals. Methodological quality was assessed using the Quality Appraisal of Reliability Studies and the Critical Appraisal Tool. RESULTS: A total of 11 studies (N = 504; 34% females) were included. Reliability of the fitness tests, produced r values ranging from moderate (balance test-EUROFIT; [r = 0.75 (0.60-0.85); p = 0.0001]) to very strong (explosive leg power EUROFIT; [r = 0.96 (0.93-0.97); p = 0.0001]). Convergent validity between the 6-min walk test (6MWT) and submaximal cardiorespiratory tests was moderate (0.57 [0.26-0.77]; p = 0.0001). Concurrent validity between the 2-min walk test and 6MWT (r = 0.86 [0.39-0.97]; p = 0.0004) was strong. CONCLUSION: The present study demonstrates that physical fitness tests are reliable and valid in people with mental disorders.