In January 2020 researchers from Australia and Germany published the results of their study to assess the association between muscle strengthening exercises (push ups, using weight machines) and depressive symptoms. A total of 23,635 adults, aged over 18 years, were included in the study. Information on muscle strengthening exercises and severity of depressive symptoms was collected via questionnaires. Results showed that muscle stengthening exercises were associated with a reduced severity of depressive symptoms. This association appeared to be irrespective of the amount of muscle strengthening exercises undertaken each week.
Bennie JA et al. Muscle-strengthening exercise and depressive symptom severity among a nationally representative sample of 23,635 german adults. J Affect Disord. 2020 Jan 29;266:282-287.