RecruitingDietary supplementNicotinamide Mononucleotide Supplementation for Exercise Tolerance Improvement in Healthy Older AdultsThis is a randomized, double-blind, placebo-controlled, two-arm crossover clinical trial evaluating the effects of a patented age-reversal therapy, EGA®, compared to conventional nicotinamide mononucleotide (NMN) supplementation. The study will assess safety and efficacy in improving exercise tolerance and modulating biomarkers of aging in healthy older adults. The primary outcome is cycle ergometry constant work rate (CWR) exercise tolerance, measured as time to fatigue. Secondary outcomes include changes in peak oxygen consumption (VO₂peak), critical power, anaerobic work capacity, lactate threshold, and NAD⁺ metabolite levels. EGA® is composed of three metabolomic compounds that are endogenous to humans. The formulation has been used in prior exploratory studies and real-world applications, which have helped inform the design of this current trial.