What's the point of plyos?

[reactiontm]

I took my middle schooler to his first wrestling practice of the season and what do I see?

A bunch of puny high school basketball players jumping onto a 24" box as many times as possible for one minute.

Not one of them looked like they squat.

Is there real evidence that doing this improves anything for sports? Particularly in the absence of strength work?

Looking at it from the principle of specificity, there are no circumstances in a basketball game where you'd be required to do this, you never jump onto a box during a game, and jumping repeatedly below your limit doesn't seem likely to increase your max jump.

Only thing I can imagine is that they are damaging their joints.

Can anyone point me to some valid research that disproves this?

[Trent Bologna]

I completely agree. Fire the coaches if they won't teach them how to squat and find somebody who can. Plenty of qualified individuals on this website actually. As far as jumping, WHY DON'T THEY JUST PRACTICE MORE LAY UPS??? Sorry this shit just makes me sick.

[madmaxaus]

Plyos can be useful if they're programmed correctly. Are they useful for kids.. No.

Wrestling is a weight class sport though, it's very hard to have run a good strength program when you're cutting weight every week.

[Kyle Schuant]

Maybe it's not useful to have 15 year olds trying to cut weight.

[Dan Miller]

My HS track team did plyos twice a week as our pre-season conditioning for those not in winter sports. Jumpers, throwers, sprinters, and distance runners all did the same program. The coach must have had an 8-week program on cards that he used every year. It was a progressive program - the heights of the boxes, number of jumps, complexity of each drill increased gradually through the winter. We'd set up 2-3 lanes in the gym, so you'd go through a drill then wait your turn while everyone else went before the next drill. The throwers (heavier guys) had their own lane with the reinforced boxes that didn't go quite as high. Nothing stupid like max jumps in a minute, never had anyone injured in practice.

I was a distance runner, so I did endurance runs 2-3 times a week on non-plyo days. The throwers lifted, not really sure what the jumpers and sprinters did. It seemed useful - better than nothing at least, and safer than running outside in the winter. I never got the typical runner's injuries (shin splints, tendinitis, etc) the years I did the whole program. Missed it as a freshman (swim season) and a senior (ankle sprain, few weeks of PT), and those were the seasons where I did have to deal with injuries.

[boot29342342]

[snip]

Is there real evidence that doing this improves anything for sports? Particularly in the absence of strength work?

[snip]

Only thing I can imagine is that they are damaging their joints.

[snip]

Can anyone point me to some valid research that disproves this?

I read recently in the Sports Gene book that training can improve one's vertical jump only a small amount--it is largely genetic, and it's determined (among other things) by the length of one's Achilles tendons. This is discussed in the chapter about high jumpers, I believe (though he might touch on it in other chapters--I don't have a searchable copy nearby).

And, speaking of Achilles tendons--tears are a fairly common type of injury that people sustain from box jumps. I've only seen informal discussion of this online. Maybe someone else who is more knowledgeable or has more time can point to some research.

[Kenny Crox]

Deleted. Posted twice by accident.

See below.

[Kenny Crox]

I took my middle schooler to his first wrestling practice of the season and what do I see?

A bunch of puny high school basketball players jumping onto a 24" box as many times as possible for one minute.

One Minute

Performing jumps for one minute provides a conditioning aspect to training.

However, it is counterproductive in the development of power and the stretch reflex.

Plyometric Rep Range

Speed and power are reliant on ATP (Adenosine Triphosphate) as the energy source.

ATP is depleted with intense training method in approximately 12 seconds.

Thus, have an athlete preform plyometric movement, such as box jumps is ineffective.

Not one of them looked like they squat.

Is there real evidence that doing this improves anything for sports?

Yes, that is the short answer.

However, first you need lay the foundation for plyometrics.

Particularly in the absence of strength work?

Strength is the Foundation

The foundation of Speed and Power are built by increasing Limit Strength (maximum strength).

With kids this age, Limit Strength need to be the focus.

Some ploymetric training can be added into the mix.

However, performing 60 seconds of ploymetric box jumps is NOT going to work.

Looking at it from the principle of specificity, there are no circumstances in a basketball game where you'd be required to do this, you never jump onto a box during a game, and jumping repeatedly below your limit doesn't seem likely to increase your max jump.

Basketball Players

There nothing wrong with having Basketball Player performing box jumps. It can be an effective tool.

"Jumping Below Your Limit"

This one of the problem in 60 second jumps.

The Jumping Rule

1) 1-5 Reps Per Jump.

This caters to the fact that you going to run out of ATP (gas) in about 12 second. .

2) When jumping power output drops, STOP. Continuing to preform jumps turn it from a power movement into an endurance one. That is NOT what you want.

3) Cluster Sets. This is a set of reps with a rest period between repetitions.

Research shows that approximately 50% of your ATP is restored to the muscles with a 30 seconds rest.

Research shows that close to 100% of your ATP is restored to the muscles in a 3 minute rest.

Thus, once power output falls off, an athlete need between 30 seconds to 3 minutes before they begin jumping again.

Only thing I can imagine is that they are damaging their joints.

No Joint Damage

There is virtually no joint damage in jumping from the floor up on a box.

Force = Mass X Acceleration

Trauma to a joint in jumping comes from the landing impact force.

Jumping UP On Box

In jumping up, the acceleration in going up decreases. Thus, in jumping up on a box, the acceleration (speed) is closing in on zero.

This means jumping up on a box decreases the impart force.

Drop Jumps

Jumping off a box dramatically increases impart forces.

Here an example...

Plyometric Bench Press Training For More Strength and Power
http://www.liftinglarge.com/Plyometr...r_ep_52-1.html

Research in this article demonstrated that dropping a 10 lb ball 42 inches created an impact force of 90 lbs.

Thus, dropping/jumping off a 24 inch box dramatically magnifies impact force.

Jumping up on to a box, there is very little impact force...joint trauma.

Can anyone point me to some valid research that disproves this?

We covered a lot of ground.

Specifically with point do you want valid research on?

Kenny Croxdale

[Dan Miller]

And, speaking of Achilles tendons--tears are a fairly common type of injury that people sustain from box jumps. I've only seen informal discussion of this online. Maybe someone else who is more knowledgeable or has more time can point to some research.

The "what's wrong with crossfit" thread on another site documented dozens of Achilles ruptures from box jumps. Risk factors seem to be performing box jumps in high-reps or in a fatigued state (supersetted with DL's or running). Box jumps and depth jumps are intended to be done for low reps in a set, limited reps per day, and with adequate rest in between.

[Dan Miller]

The research you're looking for is Verkhoshansky, the Russian guy who developed plyometrics. One edition of Supertraining by Mel Siff was co-authored with him I believe.