Kaiser Permanente's Health Encyclopedia on aerobic fitness recommends at least 30 minutes a day of moderate exercise to maintain good heart health. Bicycle commuting guarantees at least that much exercise by making it a regular part of your daily routine.
The actual calories you burn while riding your bike depend on your weight, speed, distance and other factors. Check out our Bike Commute Calculator to see how many calories you can burn on your commute.
The Benefits of Bicycling by essortment recommends bicycling for being a low impact form of aerobic exercise. Jogging or cycling through middle age can delay ageing by 12 years according to this article in the Daily Mail. Cyclists live longer according to the study cited in this Health Care Magazine article.
Always wear a helmet and follow the other safety tips on 511.org's bicycling section to make sure that you avoid crashes. Make sure your bike fits you properly. A properly fitted bicycle helps you spend less energy and prevents injuries to your joints. Many bike shops will provide this service for free with the purchase of a bike or for a fee if you bring your own bicycle. How to Make Your Bike the Perfect Fit by eHow gives tips for how to perform a bike fitting yourself.
There is no age limit on bicycling. The low impact and low intensity nature of bicycle commuting make it accessible for all ages. The blog Cycling for Boomers Plus has a wealth of articles on bicycling in your 50's and beyond. Mavis Paterson at 70 years of age completed a 6,000 mile bike trip through Canada to raise money to support people affected by cancer.