Sleds Training for Acceleration Development - Part II
By Bruce Kelly
After some further experimentation on myself and my athletes as well as listening to other coaches’ thoughts on sled training, I wanted to expand further on my previous article on sled training. Some of this will expand on the previous article and some of it is new thinking on sled training.
One way to think of sled training is as a functional single leg press. You can put your athletes into functional positions(i.e. standing and moving) and strengthen them especially their lower bodies and core.
Previously, I mentioned loading parameters and the so-called 10% rule which is that the load shouldn’t exceed 10% of bodyweight. As Boyle and others have pointed out, the load is largely dependent on the surface on which the sled is being used. It is simple physics or more specifically coefficient of drag(COD). 100 lbs. on an artificial track is a lot different than 100 lbs. on grass—try it and you’ll find out. If the sled can’t be moved at the speed you want with the mechanics you’re looking for then you have to change the load or the surface you’re using or both.
It also should be made clear that sled training is working on special strength not specific strength. Special strength is strength that is converted to usable strength through your technique work and actual running drills. With sled training we aren’t necessarily trying to overload running per se but trying to develop usable strength and force application technique that will enhance our running. So though the mechanics of sled pulls and pushes may not mirror those of running it is very tough, if not impossible, to move a well loaded sled if your mechanics aren’t good and you are applying force properly. Try doing a sled push with your butt way up in the air—it ain’t happening. The posterior power chain—hips, knees, and ankles have to be well aligned to properly apply force and move the sled.
As I said in my previous article, I believe sled training is best used for developing acceleration strength so I would keep my distances to 10-20 meters and my rest periods relatively long to ensure good recovery. If you group the athletes by 4 or 6 and they do “relays”, by the time an athlete’s turn comes up again they should have adequate rest.
I would suggest emphasizing quality and max effort over volume so 6-8 efforts in a workout should be sufficient if done with 100% effort and good recovery. These could be a combination of forward pulls/runs and pushes.
A final thought on how the sled should be attached. It appears the best way is to attach the sled via a waist belt. The problem with shoulder harnesses is that though they distribute the “force” over a greater area frequently the athlete will bend at the waist in order to move the sled. This will just lead to poor force application technique and defeat part of the purpose for using the sled in the first place.
I hope this article clarified some things from the first article as well as adding a few tips on their use. If you are working on acceleration work with your athletes look on the sled as another tool in your toolbox to enhance their performance.
Good luck, stay healthy, and train smart.
Recommended Athletes' Acceleration