Dear Alice,

I've been trying to add a little exercise to my routine this spring — some biking, rollerblading, and a little running mostly — but I'm finding that it doesn't take very long for me to be completely out of breath and miserable. The last thing I want to do is give up, since I haven't been too active this winter and don't want to completely vegetate this summer. Will I build some endurance by just doing more of what I've been doing, or am I bound to be gasping for air whenever I try to have some fun outdoors?

You may want to slow down, but don't give up! Biking, rollerblading, and running are excellent for increasing cardiovascular fitness, improving coordination, and strengthening muscles. However, you may be exercising at an intensity too high for your current endurance abilities. Figuring out an appropriate training intensity is a good place to start. Each individual has an optimal level of physical activity that allows for the best use of oxygen and energy. Starting out at the level that’s right for you will help build your endurance but not exhaust you. You can monitor this throughout your activity through both the subjective measures of how you feel and through your heart rate. The following formula from Mayo Clinic can help you determine the "target heart rate zone" for your training:

1. Subtract your age from 220 to get your suggested maximum heart rate. For example, if you’re 20 years old your maximum heart rate would be 200.
2. Calculate your resting heart rate by counting your heart beats per minute when you're resting, such as first thing in the morning. It's usually somewhere between 60 and 100 beats per minute for the average adult. In this example, perhaps your resting heart rate is 80 beats per minute.
3. Calculate your heart rate reserve (HRR) by subtracting your resting heart rate from your maximum heart rate. Using these calculations, you would subtract 80 from 200 for a total of 120.
4. Multiply your HRR by 0.7 (70 percent). Add your resting heart rate to this number. Continuing this example, you would multiply 120 by 0.7 to get 84, and then add 80 for a total of 164.
5. Multiply your HRR by 0.85 (85 percent). Add your resting heart rate to this number. So, in this case, you would multiply 120 by 0.85 to get 102, and then add 80 for a total of 182.
6. The two numbers you calculated are your training zone heart rate. When you’re physically active, try to keep your heart rate between these two numbers. In this scenario, the training zone would be between 164 and 182 beats per minute.

When you first begin to be physically active, the appropriate intensity level will likely be on the lower end — working out at a higher intensity could leave you worn out and gasping for air. If working at the lower target heart rate is too strenuous for you to sustain for twenty minutes, begin by working at the fifty percent level. After a few weeks, when you feel that your endurance and strength have increased, you can gradually increase your training intensity (such as going uphill on the bike, going for longer periods of time, or changing the bike gears). You may be able to tell you're ready to increase your training when you're not feeling tired from your activity or your heart rate is staying low. Always remember that even if you try to increase the intensity and it feels like too much, you can slow down again. Believe it or not, physical activity will become easier; as your heart strengthens, it takes less effort to pump blood to your lungs and tissue throughout your body.

A few more tips: it also helps to slowly warm up before any physical activity by easing into your activity of choice to warm up your muscles. In addition, be sure not to overdo it in terms of the duration and frequency of workouts. Start out with twenty to thirty minute sessions, working slowly up to a longer session (if you wish to do so). It’s best to avoid really intense activities every day of the week — this could lead to burnout. Instead, try to aim for three to five times a week, of varied intensity and type of activity. If you smoke, cutting down or stopping will help increase lung capacity. Given that you are just starting out a new routine, you may also want to speak with your health care provider to ensure your regimen is appropriate for your fitness level and personal health history. You can also check out the Fitness section of the Go Ask Alice! Nutrition & Physical Activity archives for more ideas.

All the best,

Alice!