150 years ago when I was a high school football player the St. Louis Football cardinals hosted an event called "Pros for Preps." Where current coaches, and coaches from all over the country came in and taught some aspect of strength and or conditioning to local high school coaches and kids.. like me... through hands on drills and labs. One of the best sessions was the coach from the K.C. Chiefs who taught plyometric training (or jump training, or Mr. Sillywiggles, whatever it's called these days). This gentleman (who's name I wish I remembered) spoke for 90 minutes, 10 of it was about jumping, 15 were about programming, the next 60 minutes were about landing. Let me repeat that: he spent 4 times as much time teaching us to land as he did explaining how to add plyometrics into our training. Fast forward 17 years and go to youtube search for "plyometrics" you see all kinds of terribleness.
Most of which comes from a lack of understanding of what plyometrics can do, and should be asked to do. The most common mistakes I see are:
1) Too high. Whaddaymean to high? Mike Boyle has talked about this, but when you jump, you should land in a good athletic position. It doesn't matter if you're jumping over a hurdle, onto a box, or just up. The whole point of these drills is to build reactive strength, and to get athletes prepared to land and keep playing, not to see how high you can get your feet.
2) landing on your heels. First off you'll rattle the chicklets out of your head. Secondly, your Plantar Fascia, ankles, Knees, hips, low back will hate you. Land mid foot and ACTIVELY absorb the impact. Don't stay rigid, catch the ground with your feet.
3) That's hard, it must be useful. Not every sport requires this type of training, and not every athlete should be doing it. If someone has a ton of reactive strength, but little to no limit strength? You're wasting your time. Athletes who have very little control over their bodies should at most be doing "jump and stick" types of movements, not long chains. They need to reset to learn to control their bodies in space. Like anything else, the right training for the right athlete.
4)It ain't cardio. If you're training for rate of force development, you shouldn't be doing 1+ minutes of jumps. This not plyometrics, it's high impact aerobics. Stop jumping for conditioning.
Let's put it this way: If I asked you to do a standing medicine ball throw, how far do you think it would go? If I asked you to take your time and do 10 in series.. probably about the same. Now if I asked you to stand in one spot and throw it for a minute or more, how far do you think it would go in the last 15 seconds? Not very far. A major part of jump training is about teaching your muscles to be as INEFFICIENT as possible, to turn on all of your muscle fibers at one time. If you use it as cardio, you are teaching it to be as EFFICIENT as possible. Congratulations, you've created a paradox. Which means: you're wasting your time.
I am not saying no one should jump, but just because "the NFL guys do it." or "I saw trainer X on youtube doing it" is not a valid reason. Jump training can be very effective, but it is also hard to recover from, and can create a lot of wear and tear. As such it needs to be targeted, programmed sparingly, and incorporated intelligently.
Hat tip to the guys at 70sbig.com for posting this video that inspired this post:
Gunthor jumps and lands very well.. and he has a sweet mullet.