I’m pretty sure you’ve all heard about how you should be exercising within your target heart rate (THR); and if not, well then, let me be the first to introduce you to your THR.There are quite a few ways to determine your heart rate. Some are simple little formulas while others are a little more involved (be not afraid mathematician haters… there is no FOILing or square rooting, all you need is a finger and a calculator!)
However, before we jump into the murky waters of math, let me first explain why it’s important to know your THR. When exercising, it’s important to know to what extent you are working your body out. Are you being safe and effective, or are you above or below that line? If you’re under-exerting yourself, you’re not getting anything more than an M&M’s worth of caloric burn, and if you’re over-exerting yourself, you’re burning more than your body can manage which could lead to dizziness, dehydration and a slew of other bodily issues.
Your THR is your benchmark and you should be keeping an eye on that number, especially when doing cardio or aerobic exercises.
One of the most effective formulas in determining your heart rate is called the Karvonen Formula. For accuracy purposes, it’s suggested that you measure your resting heart rate first, and to do that you will need to take your pulse for 1 full minute before getting out of bed in the morning. Just check your pulse on your wrist and write down that number. It’s also best to do it at least two if not three days in a row and to find the average. Once you have that number, you can plug it into this formula:
220 – age = Maximum heart rate
Maximum heart rate – resting heart rate = heart rate reserve
(Heart rate reserve x 65% to 85% training) + resting heart rate = low and high THR
So for example, a 30-year-old with a resting heart rate of 60 would do as follows:
220 – 30 [age] = 190
190 – 60 [resting heart rate] = 130
130 (.65) = 84.5 + 60 [resting heart rate] = 144.5 (low-end)
130 (.85) = 110.5 + 60 [resting heart rate] = 170.5 (high-end)
So your THR would be between 144.5 – 170.5.
This gives you an indication of how fast or slow your heart should be working while exercising. Now all you’ll need is a heart rate monitor to plug this information into so you can easily see where your heart rate is while exercising. This will really help to make your workouts more effective and keep you training safely.
And if you’re really freaked out by the math, here is a great site that allows you to plug-in your age and resting heart rate and it does the math for you, www.sparkpeople.com.Anne Marie Costanzo is a nationally certified personal trainer and owner of Little Black Dress Personal Training. She can be reached at firstname.lastname@example.org or (914) 841-1121.