Taking your heart rate can tell you a lot about how healthy you and your cardiovascular system are. Normal heart rates vary depending on your age and what you're doing (your heart beats faster when you're exercising and slower when you're resting.) There is a wide range of normal heart rates, but a heartbeat that's too fast or too slow may be a symptom of a serious heart problem.
According to the American Heart Association, a normal resting heart rate is 60 to 80 beats a minute, or about one beat per second. Well-trained athletes sometimes have resting heart rates as low as 40 beats per minute, but for those who exercise only casually or not at all, a heart rate this low is not normal. It is best to take your heart rate before you get out of bed after a night of sound sleep.
Your heart beats faster when you're active, but you don't want it to beat too fast. Doctors and trainers often refer to a healthy exercising heartbeat as a "target heart rate." For moderate exercise, a simple way to tell if you're working too hard is called the "conversational approach." If you can talk while performing your exercise, you're not putting too much stress on your heart. If you run out of breath easily, you probably are.
It is best to keep track of your precise heart rate during exercise. You can do this manually by taking your pulse, but many modern exercise machines have built-in heart monitors.
Target heart rate is determined largely by age. If you're 20, strive for anywhere between 100 and 170 beats per minute. If you're 25, go for anywhere between 98 and 166. If you're 50, you'll want to keep your heart rate between 85 and 145, and if you're 70, a healthy exercising heart rate is between 75 and 128. The lower end of the target heart rate range is better for burning fat, while the higher register is best for cardiovascular training.
Your maximum heart rate is roughly 220 minus your age.
These are only general guidelines, however. It is best to discuss your target heart rate with your doctor before you begin an exercise program.
Well-trained athletes have low resting heart rates because their cardiovascular systems are in great shape and can move blood throughout the body more efficiently. People with unhealthy cardiovascular systems have high resting heart rates for exactly the opposite reason.
Many things affect your heart rate. They include your level of activity, your level of fitness, your body position, your body size, your emotional state and your use of medications or drugs. Stimulants such as caffeine cause your heart rate to rise, while depressants cause it to fall.