Max HR or Threshold HR, which should you use?
Depending on the plan you follow, how your coach operates or what type of training tech you use, at some point your bound to come across the use of HR training zones as a form of regulating your effort. Heart rate is a great thing to be aware of, monitor and refer to as it’s a real time measure of your body’s true work rate at that moment. And if you want to get really nerdy then we can look at time spent in specific zones to calculate the type(s) of energy your body likes to utilise – fat vs carbs etc… But that’s a whole different conversation!
There are two main methods of formulating your HR training zones; Maximum HR and Threshold HR. So, what are the differences between them, and which is best suited to you and your level of training and performance?
Maximum HR is the most universally accepted method for calculating training zones. If you use a Garmin watch for example, the default zones will be calculated using this method (although they can be changed in the settings). This method simply subtracts your age in years from 220 to give you a maximum HR – the HR which you should never exceed. For example, a 30-year-old would yield a MHR of 190bpm and the 5 classic zones would be built around this finding. (see the table below).
MHR is a great way to measure your effort if you’re new to exercise, are generally deconditioned or suffer from certain health considerations. However, for those chasing performance goals or for those who are advanced in their training, the ceiling HR calculated may actually be lower than what is safely achievable. Enter the Threshold HR…
Threshold HR is the ceiling heart rate that an athlete can maintain while still clearing lactic acid quicker than it accumulates in the muscles. To calculate this an athlete is required to complete a sub-maximal fitness test. Something like a 30-minute time trial, 5k run best effort or a 20-minute power test on the bike (FTP test). Effectively you need a solid 20 minutes worth of HR data from a period when the athlete is working very hard. The average HR for that 20-minute segment reflects the threshold heart rate. This number is then used as the initial input for calculating training zones. (see the table below).
Maximum HR vs Threshold HR for a 30 year old athlete with a threshold HR of 172bpm and a resting HR of 50bpm. This table reflects running HR zones
This way of calculating training zones is far more suited to the advanced athlete because of the testing that is required, but reflects individuality in a way that MHR cannot. It also differs between sports, so triathletes for example, will need different training zones for run and bike sessions. This may carry over to runners who like to mix up their training between road and trail surfaces.
Personally, I like to use threshold HR as a form of physiological feedback among other factors as training for endurance sport inherently employs an 80/20 split across intensities (80% of the volume below threshold and 20% above threshold), so this fits well for the needs of my athletes and the type of events that are undertaken – ultramarathon and Ironman mainly!
If you'd like to find out more about appropriate training strategies for you as an individual why not book a no obligation, FREE Discovery Call with head coach Ash, here!