Plyometric exercise promises to get your feet off of the ground – both of them at once! This group of exercises, also called “jump exercise” or “shock exercise,” involves propelling your body into the air.
Most of the exercises that we do, like squats and curls, use what’s called concentric muscle action. This type of muscle action involves the fibers in your muscles shortening.
Plyometrics focus on what’s called eccentric muscle action – this type of muscle action is when your muscles fibers generate force by lengthening. Our muscles can generate a tremendous amount of force this way and incorporating more eccentric muscle action into your exercise routine can be a good way to increase your strength and flexibility.
Most plyometric exercises involve jumping, usually onto a sturdy box or exercise bench or jumping over a low obstacle. That could be a cone, a low bench, or even a mat or lines drawn on the ground. In squatting down, you stretch and “prime” your muscles as you bend at the knees, and then the force is exerted as you straighten your legs to jump.
As you land the jump, your muscles get an additional stretch. According to WebMD, this additional stretch allows you to exert more force on the following jump.
You don’t need a box, and you don’t need to keep your legs together to do a plyometric exercise. Lunges – stepping out with one leg and then stepping back and out with the other – require no specialist equipment, and they focus more on speed and flexibility than on strength straining.
Most people – and most sources, including WebMD – consider plyometric exercises to be almost exclusively for the lower body. There are plyometric exercises out there for the upper body, however. In a plyometric push-up rather than just reaching arms-length you might actually launch your upper body off of the ground and come back down. If you want to challenge yourself, try clapping your hands while your upper body is in the air.
With a weighted medicine ball, you can work in even more upper-body plyometrics. Remember jumping-jacks from grade-school? Act like you’re going to do a jumping-jack but hold a weighted medicine ball close to your chest. As you jump, raise the medicine ball above your head. On the next jump, instead of raising the ball, push it out in front of you.
A great partner-workout can also involve catching and throwing the weighted medicine ball. Launching the medicine ball means applying more force, even if it’s a force very similar to that applied in a push-up.
The only difference is that the force is being applied to the ball instead of the floor. In catching the medicine ball thrown by your partner, you’re also getting a better workout as you resist the force of the ball to slow it down.
Changing the Intensity
You can change the difficulty of the lower-body plyometric exercises by changing how many jumps you want to do in a given amount of time, or by changing the height of your jump. If you’re using a mat or markings on the floor this can be perfectly safe, but if you’re trying to jump onto something, start out with something low and make sure that it can support your weight. Many gyms and most CrossFit centers will have boxes specifically for plyometric exercises.
Any time that you do a plyometric exercise with a medicine ball, you also get more adaptability than you have with lower-body plyometric exercises. The weight in lower-body plyometrics comes from the weight of your body.
You can’t change your body weight very easily every time that you want an easier or harder work-out, but you can always go for a lighter or heavier medicine ball.