Knowledge Level: Beginner
British Cycling Member Bob e-mailed in the following question:
“I have been using the and the training is generally going ok. The query I have is about Heart rate zones. My threshold test gives me a threshold of 174. However when the training plan wants me to ride in zone two it is nearly impossible to stay down in that zone. Minimal effort sees me in low zone 3.
Maximum heart rate I have seen is 192 briefly, resting heart rate is 60 and I am very comfortable riding in the 160-170 bpm range. Over the last few months my average HR on rides has decreased as my fitness has improved. I am 62 years old and 67 kg.
Do the zones always have to be fixed percentage of Threshold or should they vary as a percentage between people?”
The first area to look at is your result from your Threshold Test. If, as you state, you’re very comfortable riding in the 160-170 BPM range, I’d expect a higher figure than the 174 you achieved.
Did you ride the test as hard as you could manage? It does need to be an all-out effort in order to gain a meaningful figure from which to calculate your heart rate zones. If it’s too low, this will skew all your zones and would explain why holding Zone 2 is difficult.
It’s also possible, if you did the test on an indoor trainer, that this can sometimes give low results that don’t necessarily translate to riding outdoors. Not having to recruit the musculature that balances you on a real bike outside, a lack of a cooling headwind and reduced motivation from boredom have all been suggested as reasons for the lower heart rates attained relative to your perceived exertion on an indoor trainer. The exact mechanism isn’t 100% understood but it is a commonly seen phenomenon and it can be worthwhile to produce two Threshold value and two sets of training zones, for inside and out.
Finally, were you appropriately rested before the test? If not, this can also flatten the heart rate value you’re able to achieve.
We’d suggest, taking a full days recovery and then conducting a new outdoors Threshold Test in place of your midweek session. Make sure you go as hard as you can and that you finish the effort with nothing left in the tank. Ideally find a gradual hill to conduct the test on as this makes it easier to maintain a constant hard effort level.
Zone 2 should be your default endurance pace and, although it can be hard to hold on climbs, if your Threshold value is correct, should feel comfortable, sustainable and easy to maintain on the flat. If you’re struggling to stay in it, again, I’d suspect that your zones are skewed too low. If it does turn out that your Threshold value is correct, then you need to back off your pace, drop a couple of gears and learn to ride in this zone. It takes discipline but is important as it’s not realistic for a relatively novice cyclist to expect to maintain a genuine Zone 3 effort for a 100 km ride. Your body won’t be able to take on and process food at this intensity and, although you may be okay for the first hour or two of the ride, you’ll struggle later on.
The percentage bands of training zones derived from Threshold are fairly consistent across the board. Variability and individuality of the training zones is down to the Threshold heart rate attained but, for these zones to be accurate for the individual, that Threshold value has to be spot on.