Therefore the TARGET HEART RATE range for a 20-year old, working at 60-80% of their max heart rate is 120-160 beats per min.
How To Check Your Heart Rate
You can feel your heartbeats in several ways, such as by placing your fingers lightly but firmly over the inside of your wrist or on your neck just below the angle of your jaw. Be careful not to put too much pressure on the neck; this can slow the heart down and can be dangerous in people with blockages of blood vessels in the neck. You can also place your palm over your heart and count the number of beats that you feel.
Once you’ve found your pulse, count the number of beats for 6 seconds. Multiply that number by 10 and compare to your recommended range. Using this method will prevent you from stopping exercise for more than a few seconds. You can take your pulse after you’ve been exercising for at least 5 minutes.
For example, suppose you take your pulse and count 13 in 6 seconds. Multiply by 10 to get 130 beats per minute. Now you know you’re in the right range. If you notice you are lower than the minimum, increase your speed/incline/intensity and try to count again. If you notice you are very high, decrease your intensity in some way.
* If you have high blood pressure, you should not be working out in this THR range.
As far as time goes, try to sustain this intensity (not including your 5 minute warm-up or cool down) for at least 20-30 minutes (minimum recommendations for health and weight loss), and up to 45-60 minutes. Of course, if you’re a beginner, you will not start an exercise program with that much endurance, but you’ll slowly build up.
Aim to reach this time/intensity 3-5 days a week.
Important health tip: If you have any questions or concerns about your exercise regimen and your target heart rate, especially if you are overweight/obese or have medical conditions, consult your doctor immediately.