Workout With Rosa Acosta: Legs and Buns (Part 2) Posted May 21st, 2012 Rosa Acosta shows you two more legs and buns exercises. (Subscribe to keep up to date with the newest workout videos from Rosa!) View the complete abs workout series: HERE Tweet bri how many sets/reps should you do? and how many times a week? thanks! Rosa Acosta Start with 3 sets and 8-10 reps, and work yourself up from there with what you feel comfortable. Also, at least 1-2 times a week as a start.