Background
There is still a lack of information regarding the impact of training on the domains that constitute quality of life (QoL), and the relationship between QoL with hormonal, inflammatory and pro-thermogenic/anti-inflammatory components. Thus, the present work aimed to evaluate the effects of combined training (CT) on the QoL of individuals with overweight-related type 2 diabetes mellitus (T2DM) and to correlate (baseline values and CT-induced delta percentage changes (Δ%)) QoL variables with hormonal, inflammatory, and pro-thermogenic/anti-inflammatory components.

Methods
Middle-aged individuals of both sexes and with overweight-related T2DM were assigned to either the control group (CONT group) or the combined training group (CTG). The CT consisted of strength training followed by aerobic training three times/week for 16 weeks. Pre- and post-intervention assessments included QoL perception, clinical variables, serum biochemical markers, and brown adipose tissue (BAT) activity.

Results
The CTG showed improvement in the perception of general QoL (20.0%) and in the physical (12.7%) and social (10.1%) domains. Significant positive correlations were observed between QoL variables with interleukin- 4 (IL-4), IL-10, IL-13, IL-33, Fibroblast growth factor- 21 (FGF-21), bone morphogenetic protein- 4 (BMP4), irisin, and BAT activity, alongside negative correlations with IL-1, IL-2, IL-6, c reactive protein (CRP), tumor necrosis factor-alpha (TNF-α) and incretin hormones at baseline and/or in the Δ% changes induced by training.

Conclusion
CT improves the perception of general QoL and the physical and social domains of individuals with overweight-related T2DM. Baseline and in the Δ% of CT change, QoL components are related with several clinical, hormonal, inflammatory, and pro-thermogenic/anti-inflammatory markers, besides BAT increased activity.