Gliclazide Enhances Exercise Performance and Recovery of Muscle Strength in Healthy Trained Individuals: A Randomized Controlled Trial

To examine the acute effect of gliclazide on exercise performance and recovery of muscle strength in healthy participants. We conducted a randomized, double-blind, placebo-controlled crossover clinical trial in 44 strength-trained men. They were allocated to gliclazide modified release (MR) (90 mg, 8h before exercise sessions) or placebo, undergo three consecutive sessions of strength exercise (four sets, 80% of one-repetition maximum [1-RM] of bench press and free squat exercise). We evaluated total volume-load (VL) (#repetitions x 80%1-RM), range of motion (ROM), insulin and glucose levels, creatine kinase MM (CK-MM), lactate dehydrogenase (LDH), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α), hemodynamic parameters, perceived muscle soreness and recovery scores. Gliclazide enhanced strength exercise performance with improvements in total VL (bench press 23.3%, p < 0.001; squat 23.2%, p < 0.001), and improved muscle recovery 24-48h post-exercise: ROM (shoulder 1.1%, p < 0.001; knee 1.6%, p = 0.004), CK-MM (-13.2%, p < 0.001), LDH (-12.8%, p < 0.001), TNF-α (-17.4%, p < 0.001), IL-6 (-5.3%, p < 0.001), muscle soreness (-17.7%, p < 0.001) and recovery scores (32.5%, p = 0.001). However, hypoglycemia events were observed in 3 participants in the gliclazide group. In conclusion, Gliclazide MR 90 mg, 8h before strength exercise, produced ergogenic effects (exercise performance and muscle recovery), although hypoglycemia was observed in 7% of subjects. Registration: "www.clinicaltrials.gov", "NCT04443777" (Primary Completion: 01/08/2020; Study Completion: 31/10/2023).