Effects of exercise and dietary interventions on serum metabolites in men with insomnia symptoms: A 6-month randomized controlled trial

Abstract

Accumulating evidence show that exercise and diet interventions are associated with improved sleep quality. Studies investigating the effects of exercise and dieting on circulating metabolomics in people with sleep disorders, particularly insomnia, are scarce. This 6-month randomized study aimed to assess the effects of exercise and dietary interventions on serum metabolites in men with insomnia symptoms. Seventy-two Finnish men (age: 51.6 ± 10.1 years) with chronic insomnia symptoms who were assigned to different intervention groups completed this study (exercise, n = 24; diet, n = 27; and control, n = 21). The Shapiro-Wilk W-test, Levene test, Spearman correlation analysis, and analysis of variance were used for data analysis. We found that exercise and diet intervention were associated with improved sleep quality and with a number of metabolites across different biochemical pathways. Although we could not show causality, our findings provide new insight into the biological mechanisms underlying the health effects of physical activity, diet, and sleep quality. Further investigation is needed to better understand the link among lifestyle, sleep quality, and metabolic health.

Keywords: (O)PLS-DA, (orthogonal) partial least-squares-discriminant analysis; 3-HB, 3-hydroxybutric acid; BCAA, branched chain amino acid; BMI, body mass index; Diet; Exercise; FM, fat mass; GC, gas chromatography; Insomnia; KIC, alpha-ketoisocaproic acid; MS, mass spectrometry; Metabolomics; NIST, National Institute of Standards and Technology; Q2, quartile 2; SE, sleep efficiency; SOL, sleep onset latency; TST, total sleep time; VIP, variable importance in the projection.

Fig. 1

Changes of sleep parameters after the interventions. TST, total sleep time; SOL, sleep onset latency; WASO, wakefulness after sleep onset; SE, sleep efficiency.

Fig. 2

The significantly altered metabolites after the intervention and Venn figure of these metabolites in the three groups. A, significantly altered metabolites in exercise group; B, significantly altered metabolites in diet group; C, significantly altered metabolites in control group; D, common and different metabolites in the three groups. Y-axis, standard data after log transformation.

Fig. 3

The intensity of significantly changed metabolites in individuals between baseline and the 6-month follow-up in the exercise and diet groups. Each line represents one individual.

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