The Association Between Insomnia Symptoms and Mood Changes During Exercise Among Patients Enrolled in Cardiac Rehabilitation

In Brief PURPOSE: Insomnia symptoms (ie, difficulty falling asleep, difficulty staying asleep, and early awakenings) are common among patients with cardiovascular disease and may interfere with the beneficial impact of exercise on mood state. This study investigated the association of insomnia symptom severity with mood disturbance and with changes in mood state during exercise in a cardiac rehabilitation (CR) population. METHODS: Insomnia symptom severity was measured using the Insomnia Severity Index upon admission to a 12-week CR program (n = 57). The Physical Activity Affect Scale was administered before and during a single bout of moderate intensity exercise to measure changes in mood state. Indices of mood disturbance included depressive symptoms (Hospital Anxiety and Depression Scale) and pre-exercise mood state (Physical Activity Affect Scale). RESULTS: Greater severity of insomnia symptoms was associated with less pleasant mood overall (r = −0.45, P < .001), including less tranquility (r = −0.37, P = .005), lower positive affect (r = −0.39, P = .003), and worse fatigue (r = 0.36, P = .005); greater insomnia symptom severity also predicted greater improvements during exercise in both overall mood state (b = 0.26, standard error = 0.10, P = .009) and tranquility (b = 0.09, standard error = 0.04, P = .04), following statistical adjustment for demographic variables and pre-exercise mood state. CONCLUSIONS: Although CR patients reporting insomnia symptoms tend to experience daytime mood disturbance, they may benefit from mood-elevating properties of exercise. Future research is needed to help optimize mood during exercise, which may have implications for improving psychological distress and CR adherence. This study examined the impact of insomnia symptoms on mood changes during moderate intensity exercise among patients in cardiac rehabilitation. Greater insomnia symptom severity was associated with larger improvements in both overall mood and tranquility during exercise, suggesting patients with insomnia may particularly benefit from the “feel-better” properties of exercise.