Heart Rate Zones

Adults should get at least 30 minutes of moderate aerobic exercise most days of the week, preferably daily. (Children need at least 60 minutes a day.) Doing less than this will minimize your health benefits. Exercise needs to be performed within the aerobic heart rate range for the body to benefit from the workout. To determine your target heart rate zone, first subtract your age from 220. That's your maximum heart rate. To get the most out of any exercise, you should target 50% to 80% of your maximum heart rate.

Heart Rate Zones

Active Zone (50 - 60% of MHR)

The lowest level you can exercise in and still increase fitness levels. For beginners or people who have not exercised for a long period of time. This zone can be for just improving your overall health. It can also be a good recovery zone for people who are over-training and need to take a break. This mode is also good for people who want to lose weight as the main source of fuel used by the body is fat stores.

Training Zone (60 - 70% of MHR)

This is the zone where the heart begins to benefit. Training in this zone will begin improve your hearts ability to pump blood and improve the muscle cells ability to utilize oxygen. In this zone stored body fat is the primary source of energy utilized hence this zone is referred to as the weight management zone. This is a good zone for long slow distance exercise as the body becomes more efficient at feeding the working muscles more efficiently especially with fat as the main fuel source.

Endurance Zone (70 - 80% of MHR)

This zone is the most effective for overall cardiovascular fitness and is often called the "aerobic zone" or "target heart rate zone". This is the optimal zone to workout in to increase your cardio-repertory capacity or the body's ability to transport oxygenated blood to the muscle cells and carbon dioxide away from the cells. After a while you will be able to cover more distance during workouts in less time. Your body will burn less glucose and more stored fat as fuel thereby working more efficiently. This zone is also effective for increasing overall muscle strength.

Anaerobic Threshold Zone (80 - 90% of MHR)

This level is where you cross over from aerobic training to anaerobic training which is called the anaerobic threshold or AT. This is the point where the body cannot effectively remove lactic Acid from the working muscles quickly enough. Lactic Acid is a by product of glycogen consumption by the working muscles. This zone is primarily for people who want to increase their performance levels. You would characterize this zone as hard. During this zone your muscles are tired, your breathing is heavy and your fatigued. The benefit of training in this zone is you can increase your body's ability to tolerate and deal with lactic acid for a longer period of time as the enzymes in your muscles responsible for anaerobic metabolism are increased. For competitors it is good to know your anaerobic threshold as many fit athletes can compete at or about their anaerobic threshold.

VO2 Max Zone (90 - 100% of MHR)

You will only be able to train in this zone for short periods of time. You should not train at this level unless you are very fit. In this zone lactic acid develops very quickly as you are operating with oxygen debt to the muscles. The value of training in this zone is you can increase your fast twitch muscle fibers which increase speed. You will not be able to stay at this level very long and should be used in intervals or sprinting work at the track.

*Heart rate variations or a reduction in heart rate for a given intensity is usually due to an improvement in fitness but a number of other factors might explain any variation:

1. Dehydration can increase the heart rate by up to 7.5%.
2. Heat and humidity can increase the heart rate by 10 beats/minute
3. Altitude can increase the heart rate by 10 to 20%, even when acclimatized