Effects of a Hypocaloric Diet Plus Resistance Training with and Without Amino Acids in Older Participants with Dynapenic Obesity: A Randomized Clinical Trial

Background/objectives: Exercise and nutrition may be useful strategies in dynapenic and sarcopenic obesity management, but the identification of treatment modalities aimed at improving this condition is still lacking. We compared the effect of a five-month hypocaloric diet plus resistance training (RT) with and without essential amino acids (EAAs) on body composition, physical performance, and muscle strength among older adults with dynapenic obesity (DO). Methods: Older individuals (n = 48) with DO [(BMI ≥ 30 kg/m2 and/or high waist circumference and low handgrip strength (HGS)] were randomized into two double-blind groups (RT without EAAs vs. RT+EAAs). All participants followed a hypocaloric diet (1 g of proteins/kg spread over three meals) and RT for five months. Pre- and post-intervention assessments included the body composition (DXA), Short Physical Performance Battery (SPPB), HGS, one-repetition maximum (1-RM), and maximal isometric torque with an isokinetic dynamometer. Results: Both groups reduced body mass (RT: -4.66 kg; RT+EAAs: -4.02 kg), waist circumference (RT: -4.66 cm; RT+EAAs: -2.2 cm), total fat mass (RT: -3.81 kg; RT+EAAs: -3.72 kg), and compartmental fat mass with no between-group differences. Both groups improved 1-RM strength (33-47%), isometric torque for body mass (RT: 14.5%; RT+EAAs: 10.6%), and functional performance (chair stand (RT: -3.24 s; RT+EAAs: -1.5 s) and HGS (RT: -2.7 kg; RT+EAAs: 2.9 kg)) with no between-group differences. Conclusions: A moderate hypocaloric diet combined with RT improves body composition and physical function in DO participants, but EAA supplementation did not provide additional benefits.