im currently weighin in at 173lbs and 5'10. i am going on a beach trip with my gf and her fam in mid july and want to do whatever necessary to be in the best shape when her fam sees me in my bathin suit. i want to lower my bf yet at the same time i want to gain muscle mass.. im thinkin about going heavier and reducing the amount of reps i do on my workouts and incorporating cardio as well. i currently workout 4-5 days a week. how many days and how long should i do cardio for? my bf right now is 13% i have good abs but i need to reduce my bf to get better definition. thanks!