I ditto everything said....
Awhile back I used to bike 20-27miles a day, talk about some ripped quads and abs. Anyone thinkin of doing it, look into getting some good quality biker shorts with double stitching and good gel padding..... sitting on a carbonfiber seat for an hour can hurt the kids and make you infertile simultaneously. Also get light colored "Underarmor" or biking shirt, because 10-15mph wind resistance can be irritable on the skin if you have loose clothing. Personally, I love "UnderArmor", it's elasticity clings tight to the skin and is virtually unnoticeable, second to being naked. Along with the good clothing, you need good gloves, cuz there is a high ratio of vibration felt on the cushiest handlebar grips, so I suggest you look into Pearl gell gloves. They're awesome and you wont have the aches in your arms and hands after a long bike ride.
Hopefully, this is helpful. Next on the list would be bikes, but you can do your own research for that cuz that's a whole different thread!!