Effects of Accentuated Eccentric and Maximal Strength High-Resistance Training Programs with or Without a Curcumin-Based Formulation Supplement on Body Composition, Blood Pressure, and Metabolic Parameters in Older Adults

Background/Objectives: This study compared the effects of high-resistance training (RT) programs, with or without curcumin supplementation, on variables commonly associated with metabolic syndrome (MetS), including body composition, blood pressure, and metabolic parameters. Methods: Eighty-one older adults at risk of MetS (BMI > 25 kg/m2, fat mass > 32%, and systolic blood pressure > 130 mmHg in half of the participants) were randomly assigned to six groups, which were comprised as follows: four experimental groups involving either accentuated eccentric or maximal strength RT with curcumin or placebo and two control groups receiving either curcumin or placebo. Experimental groups completed a 16-week full-body RT with elastic bands, while controls did not exercise. Results: The results showed that (I) all experimental protocols significantly reduced fat mass (p ≤ 0.001), with the maximal strength RT group supplemented with curcumin (Max-Cur) showing the greatest reduction, at 14.3%; (II) muscle gains were significant and comparable across experimental groups (p ≤ 0.008); (III) both systolic and diastolic blood pressure decreased similarly across experimental groups (p ≤ 0.001); (IV) metabolic parameters significantly improved across experimental groups (p ≤ 0.037), except for creatinine, which showed an undesirable peak only in the Max-Cur group; (V) curcumin supplementation enhanced the effects of both RT programs; and (VI) between 54% and 100% of participants achieved clinically meaningful improvements in seven out of ten MetS-related variables across experimental groups. Conclusions: Our findings indicate that high-RT programs combined with curcumin supplementation positively impacted all MetS-related variables. The Max-Cur RT group stood out as the most beneficial, with the greatest fat mass reductions, highlighting this approach as a promising strategy to reduce the risk of MetS in older adults.