What should your target heart rate be during exercise?

During exercise, you need to train at a pace and intensity where your heart rate increases, but not exceeds, 70% - 75% of your theoretical maximum heart rate (TMHR).

How do you calculate your MHR?
Your MHR = 70 % x (225 minus your age).

A 35-year-old’s MHR will be:
70/100 x (225 – 35)
= 70/100 x 190
= 133 – 142 (75 % will be 142)

How would you measure your heart rate?
Easy! Feel your pulse for 10 seconds. It’s easiest to feel it with two fingers in your neck – follow the arch of the trachea from the midline of your throat to either the left or right side of your neck. You’ll feel the beating pulse right where the arch of the trachea curves into the hollow “valley”. You should count 1/6th of your TMHR. For most people this will be approximately 17 –25 beats per 10 seconds.

Here's a table to your MHR according to age.

During exercise, your heart rate will increase. But this should happen within certain limits. Use the tables below to check whether your heart is overworking during exercise: