Professional Athletes around the world will run with weighted vests, parachutes and tires attached to their backs. Baseball players and golfers will swing weighted bats and clubs. All of this to get a quicker first step, to build endurance and stamina, get quicker bat and or club head speed to hit a ball. Does anyone think this same theory could be applied to firearms? Would training with a heavier grain bullet, help your grip for a lighter grain bullet ? Has anyone done this, or heard of it being done? I've seen the opposite where people train with lighter loads because the recoil of the larger load is a bit too much to shoot often (.357, .38 special comes into mind, not to mention same caliber, lighter grained bullet weights and reduced recoil loads).