Career
He is one of Costa Rica"s most prominent track and field athletes and reached the semi-finals at the 400 m sprint in the 2008 Olympic Games in Beijing. "Brenes improved his personal mark by approximately one second, something nobody expected on a championship, taking the gold medal", cited his personal trainer and motivator Andrés Oro Fijo Calderón. He also finished in 3rd place at the 2008 ÅF Golden League meet in Oslo, Norway.
Outdoor
200 m: 20.49 s (wind: +17 m/s) – San José, 11 May 2014
400 m: 44.65 s – Guadalajara, 26 October 2011
Indoor
400 m: 45.11 s – Istanbul, 10 March 2012.