You are stronger the closer your hands are to your center line... and if you can't see your hands while looking straight ahead, your hands aren't as powerful as they could be. If you find yourself losing power/control in your throws towards the end, ask yourself whether your hands are in front of you.
Have you ever done a pushup, or bench press? If the answer is no, stop reading and go do some pushups. They're good for the soul. But if you have, read on...
Question: Looking at these two images, imagine that the lifter wants to do ten reps moving his weight up or down only 2" at a time. At what position is it harder, and where is it easier for the lifter?
Here:
Or here:
Answer: He is working much harder with the weights low. There are a few reasons, but the key one is that as you stretch a muscle, it gets weaker. In the lower position, both his pecs (chest) and his triceps (pushing muscles in the arms) are pretty well stretched, and these are the key muscles he needs to push. And for any throw that involves putting uke on the ground in front of you (Osoto Gari, Seoi Nage, etc) your power hand needs to push at some point.
So we are stronger if we avoid stretching the muscles we need to perform an action.
On a related note, it seems that as your hands get further from your center you start having to rely on fewer/weaker muscles. I'm not a physiology expert, but I do know this: when we (humans) do things with our hands, we usually orient ourselves such that our hands are in front of us, and we evolved to perform better at this position. If you want to pull something with your hands at your center and arms somewhat bent, you get to use the large lattisimus dorsi and biceps, but if your hands are sticking out to your side you are now using your smaller deltoids, and maybe your trapezius. You won't be able to pull nearly as much. If you want to push something, with your hands at your center and your arms somewhat bent, you can use your comparatively large chest and your triceps, vs. with your arms out, you'll rely much more on your smaller deltoids (thouth the chest is still definitely engaged), and your triceps won't come into the picture nearly as much - possibly at all. Similar problems with your hands too high or too low. If you want to push or pull something with your hands in front of your crotch or over your head, it's going to be more difficult than if your hands are somewhat in front of your chest.
So we are stronger if our hands are placed somewhat in front of our chest.
So the moral is this: You generally want to keep your hands somewhat centered to your chest to be more powerful, whether pushing or pulling, on the ground or standing up. The rule of thumb that I give to my students is if you are looking straight ahead and you can't see your hands, then you have let your hands get behind you.
Where we make our mistakes:
- Turning in for our throw: You may start with our hands in front, but as you turn, do you leave your hands behind you? You've just lost power (though there are exceptions that make this okay on occasion).
- Pushing the bad guy off of you (particularly on the ground): When bad guy is on top of us, Judoka often try to push the bad guy away and/or to roll over. It's when we try both that that arm can tend to stay behind...
How to fix it:
Try to avoid even a moment when your hands are out of position. The issue is that once it gets behind you, it is hard to get them back. I see it a lot with Tai Otoshi. If you are having trouble with it, when you do your right-sided Tai Otoshi reps, make sure that you aren't letting your left hand (the pulling hand) get too far to the right side of your body. And see if you can keep your right hand (the pushing hand) in front of your shoulder. With a right-sided Osoto Gari, try to keep that driving hand (right hand) in front of your shoulder, and not sticking out to the side... And see if this advice helps for any other throws you are having problems with...
What do you think? Missing anything? Anyone think I am flat wrong?