True story: Playing with balls can be an excellent workout. (I’ll just wait a moment for you to stop snickering.) Whether big, inflated ones; small, firm weighted ones; or heavy ones ripe for slamming, they can really get the job done. (No, really, why are you still laughing?) These 50 tough exercises tax the core like no other—and all you need are the balls to do them. Whichever moves you pick, time each set for 30 seconds to a minute, resting a minute between, and aiming for three or four goes.

1. Stability ball: Ball pass

Lie on your back, holding the stability ball overhead. Keeping your head down, your back flat, and your arms and legs straight, bring the ball forward over your chest while raising your legs up, so you can pass the ball to between your lower legs. Extend arms back overhead and legs out, both at a 45° angle, then bring everything back in to pass the ball back to your hands. Repeat.

2. Stability ball: Ball plank

Prop yourself on your forearms on the stability ball, body long in a plank position, and hold. Don’t let your chest rest on the ball or your hips drop.

3. Stability ball: Rollouts

Kneel in front of the stability ball and place your forearms atop it. Roll your arms out in front of you, bringing your hips as straight as possible, then roll back in. Repeat.

4. Stability ball: Pot stirrers

Form a forearm plank on the stability ball. Slowly move the ball in small circles with your arms. Go one direction for half the time, then reverse the circle.

5. Stability ball: Supine lateral choppers

Lie with your shoulder blades resting on the stability ball, knees bent so you’re in a bridge position. Extend your arms straight out above your chest and clasp your hands. Slowly rotate your upper body so your hands are pointing to one wall, then rotate back up through center to the opposite side. Don’t let your hips drop the whole time. Repeat.

6. Stability ball: Deadbugs

Lie on your back, holding the stability ball in both hands. Extend your arms and legs toward the ceiling and pin the ball evenly between all four limbs. Slowly lower one arm toward the floor over your head while lowering the opposite leg straight down toward the floor as well, stopping before your lower back pops up. Bring those limbs back to hold the ball, and repeat the lowering with the opposite arm and leg. Repeat.

7. Stability ball: Jackknives

Start in a straight-arm plank in front of the stability ball. Place the tops of your feet on the ball. Bend your knees toward your chest, using your feet to roll the ball forward. Re-extend your legs. Repeat. 

8. Stability ball: Pike-ups

Come into a straight-arm plank with your toes or shins resting on the stability ball. With control, pike your hips up while bringing your head between your arms, keeping your arms, shoulders, and back in alignment. Lower down and repeat.

9. Stability ball: Ball crunches

Lie with your mid-back resting on a stability ball, knees bent, and feet flat on the floor. Cross your arms across your chest and do slow, deliberate crunches, using your abs to pull your upper body forward. 

10. Stability ball: Wipers

Lie down on a mat. Place the stability ball between your lower legs, and your arms out like a T on the floor. Holding your legs up toward the sky, ball firmly pinched, slowly lower your legs to one side, going only as low as you can control with your opposite oblique. Bring your legs back to center, then over to the other side. Repeat.

11. Stability ball: Plank walkouts

Come on top of a stability ball, face down. Place your hands down on the floor and walk out on your hands to a plank with your feet on the ball. Reverse the direction to come back atop the ball, and repeat.

12. Stability ball: Side plank

Set yourself in a side plank position, with your forearm resting on top of the ball and one foot stacked on top of the other. Make it harder by extending the top arm so fingers are pointing to the ceiling, by lifting your top leg up, or by doing both. Hold for the time allotted before coming down and doing the other side.

13. Stability ball: Flutterkicks

Rest chest-down on top of the stability ball, with your hands on the floor on either side. Pick up your feet and extend them long behind you, then proceed to kick them from the hips, as if you were swimming. 

14. Stability ball: Glute ridges

Lying on your back, bend your knees and rest your heels on top of the stability ball. Place your arms on the floor by your sides. Dig your feet into the ball while you press your hips high up, creating a plane from shoulders to knees. Lower the hips down and repeat.

15. Stability ball: Hamstring curls

Get into the glute bridge position, flat on your back, arms by your sides, knees bent, heels on the stability ball. Press yourself up so that your hips are level with your shoulders and knees. Roll your legs out straight on the ball, then curl your legs back in, keeping your hips high and your knees together. Repeat.

16. Stability ball: Reverse hyper

Lie face-down with your belly button centered on the stability ball and your hands on the floor for balance. Squeeze the glutes to raise both legs up off the floor, slightly hyperextending at the low back. Lower down but don’t touch the feet to the ground. Repeat.

17. Stability ball: Cobras

Lie with your sternum on top of the stability ball, your legs out long behind you, toes resting on the floor. With your arms by your sides, engage through the core and back to lift your chest up and open, as if you’re trying to peel it back off the ball. Lower down and repeat.

18. Medicine ball: Russian twists

Sit on the floor, holding the ball in both hands. Lean your torso back from the hips so it approaches 45° from the floor. With bent knees, keep your heels dug into the floor (easier) or lift them up to hover (harder). Start with the ball to one hip. Keeping your torso square and shoulders broad, slowly bring the ball from one hip to the other, and back. Repeat.

19. Medicine ball: Pass plank

Come into a straight-arm plank with the ball under one hand. Carefully roll the ball to the other hand, taking care to keep the hips level and avoid rocking. Keep passing back and forth.

20. Medicine ball: Wood choppers

Lift a heavy medicine ball up overhead in both hands. With soft knees and straight arms, bring the ball down in front of you and between your knees, while sending your hips back in a half-squat. Stand up while sending the ball back overhead. Repeat.

21. Medicine ball: Side-to-side wood choppers

Start in a staggered half-lunge stance, medicine ball up overhead in both hands. Bring the ball down, straight arms, in front of you, then, as you bring it back up overhead, pivot your feet so you’re facing the opposite side of the room. Chop the ball down again, and repeat.

22. Medicine ball: Ball-to-toes crunches

Lie on your back, medicine ball in both hands. Extend your arms and legs up toward the ceiling, feet together. Engage through your abs to lift your shoulders up off the mat, aiming to touch the ball to your toes. Repeat.

23. Medicine ball: V-ups

From flat on your back, hold the ball in both hands overhead toward the floor. Simultaneously lift your arms and legs up and toward each other, meeting over your navel. Slowly lower everything back toward the floor, stopping before your lower back pops up. Repeat.

24. Medicine ball: Pass bicycles

Lie on your back. Perform bicycle crunches (alternating one knee in, other leg extended), but pass the medicine ball from one hand to the other underneath the bent knee.

25. Medicine ball: Supermans

Lie on your stomach on the floor. Holding the ball overhead, lift arms and legs up off the mat. Hold for a moment, then lower down, and repeat.

26. Medicine ball: Toes to wall

Lie down on your back with your head close to a wall, arms down by your sides. Holding a medicine ball between your feet, lift your legs up straight and over your head, tapping the ball on the wall behind you. Repeat.

27. Medicine ball: Situps with overhead throw

Hold a medicine ball and come down to sit on the floor. Lie back and perform a situp; at the top, toss the ball overhead, catching on your way down into your next situp. Repeat.

28. Medicine ball: Reverse crunches

From your back, raise your legs up toward the ceiling and hold a ball between your knees. With control, lift up your hips, sending feet closer to the ceiling, then lower the hips down. Repeat.

29. Medicine ball: Wall-ball twists

Sit on the floor with your side to the wall, knees bent. Hold a medicine ball in both hands and lean your torso back; start by bringing the ball across your waist to the hip away from the wall, then bring the ball to the other side and bounce it off the wall, catching it on the rebound. Do one side for half the time, then switch sides.

30. Medicine ball: Lateral heel taps

Sit down on the floor with knees slightly bent. Place the ball on the floor between your feet. Pick your feet up (leaving the ball where it is) and bring your feet together, hovering in mid-air. Tap your heels to the floor on either side of the ball, back and forth. Make it harder by pinching the ball between your feet and tapping the ball on the floor instead.

31. Medicine ball: Standing figure 8s

Stand holding a heavy medicine ball. Extend your arms straight out in front of you and trace sideways figure 8s in the air. Change directions halfway through the time.

32. Medicine ball: Straight-leg crunches

Lie on the floor holding a medicine ball. Send your feet up to the sky, legs slightly apart. Crunch up and bring the ball between your legs.

33. Medicine ball: Around the worlds

Lie on your back with a medicine ball. Have your knees bent with feet on the floor (level one) or feet hovering over the floor (level two), or legs out at a 45° angle (level three). Make big circles with your arms and torso, taking the ball out overhead, to the side, down toward your legs, and back. Do one direction, then switch halfway through the time.

34. Medicine ball: Leg lift with hip rotation

On your back, pinch a medicine ball between your feet. Extend legs long and 45° off the floor, and rotate your feet with the ball from east-west to north-south (as if you’re turning a steering wheel with your feet) and back again.

35. Medicine ball: Double-leg raises

Lie on your back, arms down by your sides, or with hands stacked under your tailbone to support the low back. Holding a medicine ball between your feet, slowly raise your legs so they’re at 90° above your body. Even more slowly, lower them down just to the point before your low back arches. Repeat.

36. Medicine ball: Single-leg glute bridges

Lie on your back, and bend one knee in as much as possible, placing that foot on top of a medicine ball. Keeping the other leg extended, press your foot into the ball to raise your hips up level with your torso. Slowly lower down. Do for time on one leg, then switch sides.

37. Medicine ball: Halos

Hold the medicine ball in front of your chin in both hands. Slowly circle the ball around your head in one direction, as if you’re taking it in an orbit around your skull. Continue for time, then reverse direction.

38. Slam ball: Overhead slams

Stand up, holding a slam ball overhead, elbows bent and knees soft. Forcefully slam the ball down in front of you to the floor, catching it on the rebound. Repeat.

39. Slam ball: Situps with wall slam

Holding a slam ball in both hands, come down to the floor in situp position with the toes of your bent legs touching a wall. Lie back holding the ball at your chest (easier) or overhead (harder), then sit up and throw the ball at the wall. Catch it on the rebound and repeat.

40. Slam ball: Loaded glute bridges

From your back, bend your knees and plant your feet on the floor. Hold a slam ball over your head on the floor behind you. Push your feet into the floor and squeeze the glutes to press the hips up so they’re in line between your shoulders and knees; at the same time, with straight arms, raise the ball from the floor to over your chest. Lower back to the start and repeat. 

41. Slam ball: Wood chop slams

Standing up, hold a slam ball in front of one hip. In one fluid circular motion, take the ball from the hip, out to the same side then up and over the head, turning your torso so you’re facing the other side (as if you’re splitting wood with an axe) and releasing the ball to slam it down on the ground. Snag it on the rebound and repeat to one side for time, then switch sides.

42. Slam ball: Side rotary wall slams

Stand facing away from the wall holding a slam ball out in front of you. Quickly, and with force, rotate 90° to one side toward the wall to slam the ball into it. Catch it on the rebound and repeat to one side for time, then switch.

43. Slam ball: Side-to-side rotary slams

Holding a slam ball in front of you, stand with your back to a wall. Take turns turning your torso to slam the ball into the wall behind you, catching the ball and alternating each side.

44. Slam ball: Half-kneeling slam chop

Come to a half-kneel holding a slam ball. Starting with the ball in front of your back leg, lift it up, overhead, and slam it down on the other side of the front knee. Catch it on the bounce and repeat to one side for time before switching to the other.

45. Slam ball: Slam-ball burpees

Hold a slamball in both hands while you perform burpees: Drop down to a plank with hands on the ball, do a pushup, jump your feet in, and jump up, bringing the ball overhead. Repeat.

46. Slam ball: Balancing rowers

Perch yourself atop a slam ball on your butt, so you’re in a boat pose with your torso and thighs forming a V, knees bent, and arms extended and parallel to the ground. Extend your legs out long while leaning back with your torso, then bring your knees in toward your chest, keeping arms in the same place—it should feel a little like the action of a rowing machine. Repeat.

47. Slam ball: Roll-ups

Start flat on your back, holding a slam ball with arms fully extended over your head, and legs straight on the floor. Brace through your abs to slowly peel your body up off the floor, keeping the ball high above your head the whole time (harder) or bringing it out overhead then toward your toes (easier). Reverse the motion to return to flat. Repeat.

48. Slam ball: Rainbows

Stand holding a heavy slam ball to the side of one hip. In a sweeping arc, take the ball high up and overhead to the other side of your body, without twisting your torso or unsquaring your shoulders. Arc it back to the other side. Repeat.

49. Slam ball: Punching ball

Sit on the floor with your knees slightly bent, slam ball held firmly between your feet. Lie back on the floor. Sit up, and perform a light, quick jab-cross at the ball. Lie back down. Repeat.

50. Slam ball: Diaper toss

Standing with feet wider than shoulder-width, hold a heavy slam ball in your hands in front of you. Do a sumo squat, letting the ball come down between your legs, then quickly stand and underhand toss the ball high up overhead. Catch it underhand so you can repeat.