Heart Rate

Having taken your Resting Heart Rate (RHR) we can now calculate your Training Heart Rate (THR), Heart Rate Reserve (HRR) using your Maximum Heart Rate (MHR) and Resting Heart Rate.

Firstly this is all based on a commonly used model, but it is a model so you may find slight variations. However, I find it to be spot on.

Calculate your MHR.

MHR = 220 - age in years

Calculate your HRR (sometimes also called your Working Heart Rate WHR).

HRR = MHR - RHR

Calculate your THR according to what you want to get out of your workout.

The calculation for this is to take your HRR (or WHR) and multiply it by the percentage of the effort level you want divide by 100 

For example for 60% effort

HRR (or WHR) X (60%/100) = THR for 60% effort

It can also be calculated like this 

HRR (or WHR) x 0.6 = THR at 60% effort.

Please see below for the bands you require for your goals.

Full example.

I am aged 23.

My Resting Heart Rate - 49 Beats Per Minute (BPM)

Therefore my Max Heart Rate (MHR) is:

220 BPM - 23 years = 197 BPM

My Heart Rate Reserve (HRR) or Working Heart Rate (WHR) is:

MHR - RHR = 197 BPM - 49 BPM = 148 BPM

For a 65% effort workout:

WHR or HRR X 0.65 = 65% effort HR

148 X 0.65 = 145 BPM 

or for a 90% effort Heart Rate

WHR or HRR X 0.90 = 90% effort HR

148 X 0.90 = 183 BPM

The Energy Efficient or Recovery Zone - 60% to 70%

Training within this zone develops basic endurance and aerobic capacity. All easy recovery running should be completed at a maximum of 70%. Another advantage to running in this zone is that while you are happily fat burning you may lose weight and you will be allowing your muscles to re-energise with glycogen, which has been expended during those faster paced workouts.

The Aerobic Zone - 70% to 80%

Training in this zone will develop your cardiovascular. The body's ability to transport oxygen to, and carbon dioxide away from, the working muscles can be developed and improved. As you become fitter and stronger from training in this zone it will be possible to run some of your long weekend runs at up to 75%, so getting the benefits of some fat burning and improved aerobic capacity.

The Anaerobic Zone - 80% to 90%

Training in this zone will develop your lactic acid system. In this zone, your individual anaerobic threshold (AT) is found - sometimes referred to the point of deflection (POD). During these heart rates, the amount of fat being utilised as the main source of energy is greatly reduced and glycogen stored in the muscle is predominantly used. One of the by-products of burning this glycogen is lactic acid. There is a point at which the body can no longer remove the lactic acid from the working muscles quickly enough. This is your anaerobic threshold (AT). Through the correct training, it is possible to delay the AT by being able to increase your ability to deal with the lactic acid for a longer period of time or by pushing the AT higher.

The Red Line Zone 90% to 100%

Training in this zone will only be possible for short periods. It effectively trains your fast twitch muscle fibres and helps to develop speed. This zone is reserved for interval training and only the very fit are able to train effectively within this zone.

Heart rate variations for a given intensity

A reduction in heart rate for a given intensity is usually due to an improvement in fitness but a number of other factors might explain why heart rates can vary for a given intensity:

• Dehydration can increase the heart rate by up to 7.5%
• Heat and humidity can increase the heart rate by 10 beats/minute
• Altitude can increase the heart rate by 10 to 20%, even when acclimatised
• Biological variation can mean the heart rate varies from day to day by 2 to 4 beats/minute