The stiffness in your legs is caused by the combination of lactic acid and small muscle tears from the exercise. The muscle tears are not a problem, they are how the muscles grow.
Diet can help with the lactic acid, only training can help with the muscle tears.
Good hydration is the key to cleaning the lactic acid from your system. As the other answer suggests, milk is very good for this. Research has shown that skimmed milk is far better at rehydrating you than water, or most isotonic drinks.

just keep training and eating the way you are right now. your body will build the muscle to build resistance to the vigorous physical activity soon. and i would suggest milk, it is the world's wonder drink

You just need more training. Do a very easy 10 min warm up ride and they pedal at a high cadence 70-90 rpm's in a gear that is easy to spin. Eat protein right after a ride and carbs later in the day for tomorrow. Once you reach a certain fitness level you will only be limited by your butt pain. Drink water often and eat after the first hour, a apple or banana. I like Good & Plenty to much on during the ride it just contains sugar and carbs. This may help.

http://www.ultracycling.com/nutrition/nu…

"Good food or Heathy food"- - - - "Good Heathy food"
Eat a big old hamburger preferably from a place with a sign that read EAT or EAT AT JOES. Then get back on the bike and keep riding. Waiting a week is far to long, ride every day or twice a day, if your legs are stiff and sore your not riding enough.
But seriously, I love a good hamburger after a long ride and you should reward your self. I mean if your legs feel like jello, That the greatest feeling in the world don't complain, just have a beer and eat your burger

no special food really

wle