I have been on the fitness roller coaster for over 30 years. I have been riding a bike indoors 3 - 4 times per week in a spin class, for going on three years now. I started in preparation for a Grand Canyon trip. Every ride has a different goal to achieve; hills, endurance, anaerobic threshold intervals, etc. I use a heart rate monitor to control my heart rate and to achieve each goal. It's the only form of exercise I have ever been able to sustain for this long.

The two benfits I have realized from my bicycling are the strength and endurance in my legs and my heart rate recovery time. I was recently in Mt Shasta snowmobiling in the back country. When anyone in the group gets stuck, everybody helps, and it usually involves postholing through waist deep snow. My heart rate would jump up as high as anybody else's, but my recover time was much quicker than most, including a few guys that were 20 years younger. Of course the locals that live and work at elevation are a different story.