I started riding about 4 and a half years ago, on a hard tail mtb that my husband adjusted for me. I thought i was very fit (aerobics, weight training, walking) but I almost died the first couple of times. My husband had to push me up a small hill with the back of his hand. This was in the fall. The next spring I started riding 10-15 miles at a time, at about 12 mph average. There are tons of hills where I live. After 2 years I got a road bike and this helped me improve a lot. Riding with my husband pushes me and riding with one of my friends helps me see that I am in pretty good shape for someone who is 51. We joined a group and I am consistently the fastest woman, unless there are people who race there. I feel like I may have hit my stride (15 mph average) unless i can get a little more fearless on the downhills. I would like to improve some technical skills, but beginners need to remember to keep riding for fun and fitness. Although I wasn't fat, the middle aged spread was creeping up, despite years of regular exercise. I lost about 15 pounds from riding and now weigh what i did in high school.