Healthcare professionals have been teaching the importance of pacing yourself while exercising for years. The goal, is to push yourself hard enough to receive the benefits of being physically active, without tiring too quickly or doing undo stress to your body. Pacing yourself is especially important for beginners and the elderly.

How Do You Monitor Your Exercise Intensity?
There are three methods that are effective in monitoring exercise intensity. They are:

1. Heart Rate - number of beats per minute (bpm) at which your heart is beating
2. Perceived Exertion Scale - scale from 1 - 10 measuring your exertion level
3. Talk-Test - ability or nonability to talk during exertion

The Heart rate approach requires having the ability to measure your heart rate periodically as you exercise and calculating your target heart rate zone. First calculate your maximum heart rate (maxHR). This number is related to your age. To estimate this number, subtract your age from the number 220. Second, find your target heart rate zone (THR). This is a range at which you should try to keep your heart rate in while exercising. For the frail elderly and beginners, strive for 40-60% maxHR and for healthy individuals strive for 50-75% maxHR. So, if your 75 and healthy your maxHR is 145 bpm and your THR would be 73 bpm (low end) to 109 bpm (high end). Refer to chart for more examples. You can also monitor your progress using your resting heart rate and THR zone. As you become more fit, your resting HR should drop and you will notice being able to work harder or longer while remaining in your THR zone.

You can monitor your heart rate either on your wrist (radial artery) at the base of the thumb (palm side), or at the side of your neck (carotid artery). Use two fingers and lightly press on artery, a pulse beat can easily be felt. Count the number of beats in a 6-second period. Multiply this number by 10 to determine your beats per minute. For example, if a 6-second pulse count were 9, then the heart rate would be 90 bpm. Monitor your heart rate periodically while you exercise for best results.

Using the Perceived Exertion Scale requires rating your level of exertion. Research shows the 3-7 range correlating to 50-80% maxHR for all ages. You will be able to rate your exertion level easier with practice.

The Talk-Test is another alternative used to monitor exercise intensity. If you can talk and exercise at the same time, your are not working too hard. This means your oxygen needs are still being met. If you are out of breath, you are probably working too hard (especially if you have to stop and catch your breath). If you can sing and maintain your training intensity, you are not working hard enough.
Strive for the "conversational pace" while exercising!

How Should I Pace Myself?
Beginners and the frail elderly should aim at the lowest end of the target zone (40-50%) during the first 3-4 weeks. Increase your intensity gradually, building up to the higher end of the target zone (60-75%). You may exercise up to 85% of your maxHR after exercising regularly for six months or more. You do not have to exercise that hard though to stay in condition.

Are There Any Precautions?
Pacemakers and a few high blood pressure medications (ie. beta-blockers) can mask your maxHR. Call your physician if you are taking high blood pressure to find out if your program needs to be adjusted. You may want to use the Perceived Exertion Scale or talk test instead of Heart Rate, as they will be a better methods for you.

by Carol Glasscock, MS,PT