Reducing Drag

As a triathlete, I have read countless articles and lab tests about reducing drag. Swing by a high end bike shop and you can spend thousands of dollars to shave off a few minutes on the bike. For example, you can save 3-4 minutes if you switch to aerobars, an aero helmet will buy you about 30 seconds, and another couple of minutes if you switch to a deep dish front/disc wheel. Now all of this is based on tests at 30mph for 40 kilometers, so if you can’t go that fast for an hour (and I know you can’t so don’t try and tell me otherwise) the above mentioned time savings are diminished.

One of the areas of drag that isn’t discussed much, or at least not in this context, is in the water. If you climb on a bike and burn 100 calories, 95 of those calories are used to move forward and 5 calories are lost in fighting the wind, rolling resistance, chain friction, etc. On the other hand, if you jump in the water and burn 100 calories swimming, anywhere from 1 to 10 calories are used to move you forward and 90-99 calories are lost to fighting the resistance of the water. So we spend thousands of dollars to minimize the effects of that 5% on the bike, but it seems to me that we can get more bang for our buck by trying to minmize the 90% in the swim. Problem is, you can’t buy anything to fix bad form.

Swimming is very much like cycling in the sense that any adjustment in our position can potentially save us time. For instance, a better streamline through the water can take minutes off your time in even a sprint race, but to get a better streamline you need to be flexible. In my discussions and clinics  I put on I often demonstrate how good flexibility can overcome a host of  issues like streamlining. When I tell them that they need to stretch regularly in order to do this, I’m often looked at like I’m speaking Spanish. 

The great thing about reducing drag and swimming more effectively is that is will benefit you in a couple of ways. As an efficient swimmer, not only am I swimming faster, but I’m also using less energy doing it. I’ll use the Ironman distance as the example. Say I get out around 50 min, but I do it without spending much energy per stroke because I’ve reduced the drag. If a non swimmer gets out in 1:10, not only do I have a 20 min lead, but I’ve burned fewer calories in the water simply because it took me less time AND my effort level is lower to achieve those results, so I spent even less energy in the water. I am fresh on the bike and know I have a 20 min cushion. The poorer swimmer is tired out of the water and down 20 minutes.

Since 95% of your effort on a bike moves you forward and therefore very small gains are made in reducing drag, the same thing cannot be said on the bike or run.  Cycling and running don’t have the same technique factor. It’s more of a 1 to 1 relationship with cycling and running(or .95 to 1 to be more accurate). Put in X effort and you get X time. So the cyclist has 5 hours to make up the 20 minutes. Assuming he can average a full 1.5 mph faster, it will take him 100 miles to make up the time, but the effort level would be the same for both.  The swimming equation is more like X effort + X technique = X time. So the bad swimmer has to put in more effort to achieve a lesser result because of drag/technique. The good swimmer can lean on the good technique and ease off the effort to achieve the desired result.

So what’s the moral to this story? There’s alot of free speed in the water if you spend some time on the little things to reduce drag. It’s not as fun as buying a new cycling toy, but remember this: while wearing an aero helmet can save you up to 30 seconds during a 1 hour ride, making some key adjustments in the pool can save you upwards of 30 seconds per 100 yards. So in a sprint, you can gain 15 seconds on the bike, but over 2 minutes in the swim.

I’ll take the 2 minutes everytime.