Different protein and derivatives supplementation strategies combined with resistance training in pre-frail and frail elderly: Rationale and protocol for the “Pro-Elderly” Study - Fernandes, Alan Lins; Hayashi, Ana Paula; Jambassi-Filho, José Claudio; Capitani, Mariana Dutilh de; Santana, Davi Alves de; Gualano, Bruno; Roschel, Hamilton (Nutrition and Health, 2017)