Power to Weight Ratio

Bolder asked me if I knew what my LT watts were when I weighed more, and this spurred an email exchange, part of which is below. The reason I'm posting this is so that you can see what a DRAMATIC impact losing weight can have on your power to weight ratio in biking. In my case, though, over the past 2 years I've both lost weight AND gained power, so that's an even more potent improvement. Check out some math:

I didn't have the SRM when I weighed 128, but I know my power output was less, let's say even 15%, so let's do the math:

85% of 158 is 134.
134/(128/2.2) is 2.303 (power to weight, in kg)

I'm at 3.104 today (158/(112/2.2)), so that's an improvement of 35%????

Holy crap!

Now, let's do some more math. What if all I did was lose weight and yet not become more powerful?

134/(112/2.2) is 2.632, or improvement of 14%.

So, I must have improved my power to weight ratio at least 14%, probably more on the order of 20-25% in 2 years, as a result of getting smaller AND more powerful!

Neat!

I've put a link to the Power to Weight Chart in my Links area so when you get a Power Meter you can see where you fall. I am currently at the bottom of the "good" range. Keep in mind this chart represents values for pure cyclists. I've been told that "good" is VERY GOOD for a triathlete. My goal is to get my LT watts to 170 this season. If I stay at 112 lbs. I would have a power to weight ratio of 3.34, which puts me solidly in the upper "good" range.