Abstract Background The efect of combining green tea supplementation and intense interval training on heart stress markers and their association with metabolic disorders, including insulin resistance, remains uncertain. Aims The objective of this study was to investigate how the combination of high-intensity interval training (HIIT) and green tea extract (GT) impacts cardiac stress markers, including growth diferentiation factor 15 (GDF-15) and N-terminal pro b-type natriuretic peptide (NT-proBNP). Methods A total of 32 obese men with type 2 diabetes were randomly divided into one of four groups: 1) green tea extract (GT), 2) placebo (PL), 3) HIIT+GT, and 4) PL+HIIT. The HIIT regimen consisted of six 1 min high-intensity bouts at 90–95% maximum heart rate (MHR), interspersed with six 4 min rest intervals at 70–75% MHR, conducted three times weekly for eight weeks. The GT group received a daily dose of 800 mg of green tea extract in capsule form for the same duration. Results Repeated measures ANOVA revealed that GDF-15 levels signifcantly decreased in the GT (16.97%), GT+HIIT (26.37%), and PL+HIIT (16.02%) groups compared to the PL group. Similarly, NT-proBNP levels signifcantly decreased in the GT (18.82%), GT+HIIT (40.40%), and PL+HIIT (19%) groups compared to the PL group. Additionally, the results showed that serum glucose levels and insulin resistance decreased more in the GT+HIIT group than in the GT and PL+HIIT groups. Conclusions The study fndings suggest that an 8 week regimen of HIIT and GT supplementation can signifcantly reduce cardiac stress marker levels, improve insulin resistance, and enhance glucose metabolism in obese men with type 2 diabetes
