16. Izquierdo M, Ibanez J, Gonzalez-Badillo JJ, Hakkinen K, Ratamess NA, Kraemer WJ, French DN, Eslava J, Altadill A, Asianin X, and Gorostiaga EM. Differential effects of strength training leading to failure versus not to failure on hormonal responses, strength and muscle power increases. J Appl Physiol 100, 1647–1656, 2006