Body-Solid Medicine Balls Wrap a total conditioning routine into a tight little ball. Available in 2, 4, 6, 8, 10, 12, 14 and 16 lbs. increments. Body Solid Tools Medicine Balls add resistance to a variety of exercises and can be used to activate and strengthen core muscles that can be difficult to target during traditional training routines. Body Solid adds a textured grip and adjustable air pressure to bring modern functionality and flexibility to time-tested medicine ball exercises.