This very question was posed in last week's www.roadbikerider.com newsletter:

COACH FRED

Why Does My Weight Rise After Long Rides?

Q: Last season I logged more than 5,000 miles to prepare for a big cross-state ride. However, as I added distance, my normal 156-lb. (71-kg) weight would increase as much as 8 lbs. (3.6 kg) in the 2-3 days following a hard, long ride. And to make matters worse, I was ravenous during those days. Is this normal? I'd like to prevent the same thing happening this season. -- Jeff R.

Coach Fred Matheny Replies: I'll give you my take based on what nutritionists have told me as well as my own experience with long rides and multiday tours.

Generally, you gain weight following such rides because they exhaust your glycogen supplies. Glycogen is your muscles' primary fuel. You've essentially done the depletion phase of the classic carbo-loading regimen.

After the ride, as your body replenishes glycogen in the muscles, you gain weight for one simple reason: Glycogen is stored with a considerable amount of water.

So, much of your sudden gain is water weight and will vanish during your next big ride. This water storage is one reason that glycogen-stocked athletes will say they feel "bloated" going into an event.

As for your appetite, sure you're hungry -- you just did an enormous amount of work, your metabolism is elevated and your body is in caloric debt. It compensates (maybe overcompensates) for the deficit. This would be bad if you weren't right back into training. You'll burn the extra calories that result from this feasting. But make sure that what you're chowing on is wholesome and nutritious.

If you rode a consistent amount each week -- say, 10 hours -- your weight would probably settle at some moderate figure. But as long as you're training hard and riding long, you can expect fluctuations. That's normal.