Wednesday, April 18, 2012

Science & Swimming

I was swimming the other day, and as is often the case when I'm doing a long distance set, my mind began to wander. Because I was focusing on a smooth hand entry, I thought about a demo I used to do when I was a middle school science teacher. I used this demo involving corn starch and water to demonstrate an exception to solids and liquids. Watch the above video and see if you can make the connection as to why this demo popped in my head as I was swimming and working on a smooth hand entry.

Corn starch mixed with water produces a dilatant, which is basically a liquid with properties of a solid or vice versa. The more force you exert on the dilatant, the more viscous (or more solid) it is. If you slap the dilatant, it will take on the properties of a solid, but if you ease your hands into the dilatant, it is liquid. Let's tie this back to the hand entry in swimming.

One of the foundations of a good swim stroke is proper hand entry. Some coaches call it "clean" but I think smooth best describes what I mean by proper hand entry. A smooth hand entry implies little to no splash, because you are placing your hand into the water. A proper hand entry will not only make the rest of the pull more efficient, it will prevent you from getting that stuck or pause in the stroke feeling often occurring when you increase your stroke rate.

Inexperienced swimmers, when trying to mimic the fast stroke rate of more experience swimmers, usually end up throwing their hand, and slapping the water on the entry. And recall what happens when you slap a dilatant. And this is why the demo popped in my head as I was swimming and focusing on a smooth hand entry.

If you want to improve your hand entry, start slow. Swim slow and focus solely on being precise with the hand entry, think of it as sneaking your hands into the water. As your precision improves, you can slowly increase the speed or stroke rate. Over time, you will be able to increase your stroke rate but still keep the precision, and soon enough, you will be just like those crazy fast ITU swimmers who look like they are throwing their arms wildly around but they are actually placing their hands in the water...really really fast!


Charisa said...

Wow, that is cool.

martin briars said...

so true ! i joined the try club recently and the swim coach soon picked up on my technique (or lack of it) and how my hand isn't vertical on the's more like a spoon. The remedy to get the angle right is a slow entry an,d a concentrated push - swimming with fins is the key to getting this right - allows a slow entry and movement whilst keeping a good speed... i'm getting there.