subject: Monitoring Your Heart-rate Means Faster Fitness [print this page] One of the best ways to tell how hard you are working during a bike ride or any other exercise is to monitor your heart-rate. Using a heart-rate monitor while you train is a little like using the tachometer in your car. Just like your vehicle is happiest when driven at certain rpms, exercising at an effective intensity level will help you make the most of your training time. There is a lot to know about using a heart-rate monitor and training, much more than we can cover here. But we can offer a few guidelines and point you toward sources of more information.
A basic rule is that the harder one exercises, the higher the heart rate. Also, the longer you ride the higher your heart rate goes for the same amount of effort and workload. This is a phenomenon known as cardiac drift. If you are training for fitness and/or to lose weight, your time is best spent in the aerobic zone, which is 65 to 75 percent of your maximum heart rate. You can approximate your maximum heart rate using this simple formula: 220 minus your age. Another measure that considers other health factors is: 210 minus your age minus 5 percent of your body weight + 4 if you're male). Below the 65 percent minimum intensity level you will not see much improvement in aerobic capacity, one of the biggest factors in determining how fit you are. But, exercising at higher levels isn't really necessary if your goal is mainly improving your fitness or losing weight.
If you are training to race, the amount of time you spend in each zone varies throughout the year. In early season, spend virtually all of your riding time in the aerobic zone. Late in the year, incorporate intervals and sprints that take your heart rate into the higher zones. Because cycling is mainly an aerobic sport, even during late season riding, around 60 percent of your riding time should be spent in the aerobic zone. As your fitness improves, you'll see your resting heart rate start to drop.
To gauge yourself day to day, check your heart rate first thing in the morning and keep track of it. If your heart rate is high when you first get up, it's a sign that you may be tired from overtraining and that you should take it easy.
These are just some basic guidelines. Most heart-rate monitors include manuals. Read yours for more information. We've also got great training books that detail how to use your heart-rate monitor to train effectively and efficiently. And, if you're just beginning a fitness program or have been inactive for more than a few weeks, consult your physician.