Tailoring your cardio workout to your goals is easy if you have some way to measure your heart rate. As fitness technology rapidly increases, most people can wear a wrist device that tracks it for you. If you know your heart rate, you can speed up or slow down your workout to keep yourself in the right heart rate zone for your goals.
Max Heart Rate
Your heart rate will tell you the intensity of your cardio workout. The harder you work the faster your heart beats until you hit your maximum heart rate. To find your approximate max heart rate, subtract your age from 220.
Read more: How Does Exercise Affect Your Heart Rate?
Heart rate zones are based on that maximum heart rate number. Instead of sticking to a certain number of beats per minute, you're going to use a percentage of your maximum heart rate.
Measuring Heart Rate
To measure your heart rate, you can use a smartwatch, activity tracker or heart rate strap. Wrist devices can measure heart rate through the pulse in your wrist, which is slightly less accurate than a chest strap.
Chest straps go around your chest and sit right below your sternum. They measure electrical activity from your heart, which surges when your heart beats. It's the most accurate way to measure your heart rate but it can be a nuisance to wear the band during your workouts.
Read more: Cardio Heart-Rate Zones
You can also take your heart rate using your fingers. Put the tip of your index and middle finger over the side of your neck or the underside of your wrist to feel your heartbeat. You can count the number of beats per minute or count for 15 seconds and multiply by four to find your beats per minute.
Taking your pulse with your fingers works well if you're sitting and resting, but it's not practical if you're exercising. When you're trying to stick to a specific heart rate zone, you should measure your heart rate during your workout.
Cardio workouts affect your body differently depending on their intensity. The more intense the workout, the more taxing it is to your body. That means the workout will be shorter because you get tired faster.
The first zone is about 50 to 60 percent of your max heart rate. That's the least intense zone of cardio and is relatively easy. If you're new to exercise you should start your workouts in this zone. You'll burn some calories and build up your cardiovascular system to prepare yourself for harder workouts.
Exercise at 60 to 70 percent of your max heart rate and you're still in a relatively low-intensity zone. Some people will be in this zone when they jog slowly. It's slightly more intense than a brisk walk. If you stay in this zone during your workout you won't be exhausted after your workout. You might even feel refreshed afterwards.
Between 70 and 80 percent of your max heart rate constitutes zone 3 — the perfect zone to train for endurance activities. When you run distances or participate in other events such as a triathlon, you'll spend a lot of time in this heart rate zone. It's low-intensity enough that you can maintain it for quite a while, as long as you're trained.
Zone 4, or 80 to 90 percent of your heart rate max, is too intense to sustain for a long time. You reach this zone when going at a quick running speed, just below an all-out sprint. This is a heart rate you would hit during a circuit training workout or while doing interval training, where you work for a short 30- to 90-second burst and then rest.
The final zone, which is 90 to 100 percent of your max, is the most intense. It's incredibly hard to sustain your workout at this heart rate. Most likely this will be the heart rate zone that you hit at the end of an incredibly hard sprint. Your body will quickly hit a wall where you can't push any hard and start to slow down.