A 6-month, double-blind, placebo-controlled, randomized trial to evaluate the effect of Eurycoma longifolia (Tongkat Ali) and concurrent training on erectile function and testosterone levels in androgen deficiency of aging males (ADAM)

•Eurycoma longifolia and the practice of concurrent training for 6 months significantly improved the erectile function of men with androgen deficiency.•Eurycoma longifolia increased testosterone levels in almost 50 % of study participants.•Testosterone level was correlated with function in domains of men’s sexual health.