Put your thumb and forefinger together and press really hard. Have someone try to pull them apart - it should be pretty easy. Now that you know how using a lot of muscle feels, shake your hand out, and try it again using very little muscle. Feel almost as though you're ignoring the person who is trying to pry your fingers apart. This is part of having a positive mind - thinking that the obstacles you must overcome are no big deal.
Relaxation works better than strength.
It does on a big scale, like when you're throwing someone with Aikido. And it does on a small scale, as with this Cool Ki Trick. And while this little trick may seem to have no more applicability than impressing people at your office Christmas party, if you were a surgeon, you might find that it is the key to improving how you hold and use your scalpel. It's a fascinating pursuit finding all the different areas in your life where a relaxed approach improves your results.