I normally feel sluggish until I'm about 10 miles into a ride. Then I get what I've always called "a second wind" and usually feel really good the next 20 or 30 miles.

I have noticed there are some days that I just absolutely have "energy to burn!" For example, last Sunday when I put in my personal best of 63 miles, I did not want to stop. I could have ridden many more miles but my wife had other plans for me. But then I had a day like yesterday where I rode 40 miles and didn't feel as if I could've gone another inch. Not sure what it is. I've thought maybe it had something to do with the temp, but I'm not so sure that's it.

Regardless, those days where you have that extra burst of energy, make you feel like you're Superman!