I'm new to cycling (at age 40 years old and 205 pounds). I have been riding for about three weeks and up to about 30 miles. I am interested in riding for fitness and to lose some weight. One problem I am having is that my legs tend to burn a great deal at the beginning of a ride even when I have eaten well the night before and an hour or so before the ride. Should I be warming up before the ride to get the best effect. The burning went away after about 20 minutes, and I felt pretty good the rest of the ride, but shouldn't the beginning be the easiest? Any suggestions would be appreciated.

P.S. rides are pretty hilly here in upstate New York (I know not like some places, but nonetheless). Here is an example of my ride a couple of days ago... had to stop a couple of times on the steeper sections: 30-mile loop

Thanks much for getting an aging neophyte straightened out...