Carl those are really good points. I entirely agree that first you need to learn the rules, and use the rules before considering breaking them. If you are going to break them, make sure you are truly observing what’s happening when you do. Lastly, I believe that its generally better to do less than more, so if you are going to add or change an element, what about everything else.
To your point, I edged toward some heavier loads, when using it to train the 40 yd dash. I would use very heavy loads with a release to strictly have them set-up and “feel” tension in the start position. (big problem for a down lineman who is trained to be “balanced” in that position) This has worked very well. Later, it advanced to a step or two before the release. What I saw were positive motor control changes.
Like many things in this field, trends take over and I suspect too many people are employing heavy resistance instead of good sprint training or good strength training. The pendulum often swings too far.
Specifically related to my post about resisted sprinting;
I do use heavy resistance at times, but if we looked at the overall use across time, it would be relatively small.
The question regarding whether it would be better to do more targeted strength work is really important to me. My roots are as an Olympic lifting coach so I always like that on some level. However, I think the reasons I will employ the heavy sleds come from a few directions. One is that I work with a lot of football and rugby players. There non-specific strength and power qualities are often better developed than some other athletes including some track athletes.
Next, although I mentioned special strength, this is probably the reason I use it the least. If that is the goal, then it has probably been part of the overall strength progression. What I use the heavy sleds for the most is as a technical tool or for potentiation.
Potentiation is relatively straight forward in theory but more challenging in application. The research is still mixed, but I’m of the opinion that with a trained athlete, it works best when it is applied with heavy loads and low reps.
The technical piece is different. For many of my team sport athlete who have terrible awareness of what they are doing compared to a track athlete or Olympic lifter, the heavier resistance gives them better feedback relative to their strength/power levels. It can build a better awareness of small faults and body positions.
The second “technical” aspect I’m only hypothesizing about. As I mentioned, what I have observed that was positive, is mostly motor control issues. I have seen some very dramatic technical improvements when using this contrast method, but more so than with lower loads. So the question I asked was WHY?
One potential reason has to do with a dynamical systems view of motor control. When someone has a “stable” motor pattern with stable attractors, to move to a new pattern, you often need to disrupt the current state. I have some suspicion that that very heavy load, is effective at disrupting the stability of the system, and allows new patterning during the unresisted sprints.
So with most people I still think good strength training will give you an awful lot of benefit. Sleds may replace them if we are talking about a well programed phase of special strength. However, I think heavy sleds give us some really interesting tools for the technical aspects of teaching acceleration.