Wearing a weighted vest during workout gives you additional weight during the workout. TJ (MW 5:30pm) wears it every time we work out. I challenged him to wear it one day and now I can't get him out of it! I got the idea while in the Fresno State Athlete center. I watched a big tight end slim down to a wide receiver without changing his workout. All he did was add a vest. In only a few short months he had cut his body fat in half 24% to 12% and gained 3 tenths of a second on his 40 time. I challenge YOU to try it!