Heart Rate and Exercise


by Devin Sarno, NSCA-CPT

Everybody exercises with some sort of purpose and depending on that purpose it may be to your benefit to monitor your heart rate so you are aware of your heart rate a different levels of intensity.Especially if you are trying to optimize performance, particularly aerobic performance, you may want to pay special attention to this information and apply it to your own training.

Heart rate is a great way to measure exercise intensity. You should be familiar with your resting heart rate and your maximum heart rate. Your resting heart rate is how many times your heart beats in 60 seconds when you are completely at rest without any outside stressors acting to increase your heart rate. When you measure your resting heart rate, you will want to be sure you are not coming off a bout of activity and that you have been at rest long enough for your heart rate to return to normal. Generally speaking, most people will fall somewhere between 60 and 90 beats per minute. People who have a higher aerobic capacity may fall below 60 while some individuals in extreme cases might also range higher than 90 beats per minute. In regards to your maximum heart rate, this is the highest number of beats per minute that you likely are able to reach. Generally speaking, a good way to estimate your maximum heart rate is by using the formula (220-Age). This is fairly accurate but has a slightly less reliability for individuals older than 40.

There are a few ways you can monitor your heart rate, from fitness trackers, watches, and belts, to manually measuring your heart rate. While some methods are more accurate than others, technology offers multiple ways to monitor your heart rate. Being able to measure and read your heart rate is a great tool for improving your fitness. Ideally, you should have a target heart rate range for any exercise you perform. It is said that a good target heart rate zone is between 70-85% of your maximum heart rate. However, depending on your goal or medical history this could fluctuate.

Using this idea of a target heart rate zone will be beneficial when selecting what intensity at which to work in order to achieve your desired results. Contrary to popular belief, weight loss and fat burning actually occurs working at lower intensities. If you are looking to burn fat, you should be working near 70% of your maximum heart rate. Any higher and you are starting to get into the realm of building aerobic capacity forcing your body to rely on carbohydrates as opposed to fat for fuel. To work at 70% of your maximum heart rate and in that optimal fat burning zone would include exercises such as a brisk walk, light jog or bike. While intensity is specific to each individual, this is a good place to start.

If you are looking to maximize your calorie burn, build aerobic capacity or cardiovascular endurance, you will want to work above that 70% mark. To improve your performance at a specific heart rate percentage, you will have to work at a sustainable pace that lies just below your lactate threshold, that point of muscular/cardiovascular failure. This is another measure you should be familiar with, and while it will be different for everyone depending on fitness level, it will usually be somewhere between 80 and 90%. For recreational runners looking to run for a long duration, running at a range of 70-80% of your maximum heart rate will help improve your cardiovascular fitness. As a competitive runner, you will want to spend a decent amount of time working at or near that lactate threshold that was previously mentioned in order to optimize your performance and increase your lactate threshold. This will allow for you to work at a higher pace for a longer period of time.