How Steady Should my Heart Rate Be?

ctp046 Posts: 46
edited September 2018 in Training, fitness and health
Recently started training with a HR monitor (before it was just lots of bike rides). Working on a few things, one of which is 15 minute intervals at a given heart rate and then 5 minutes at a lower rate.

I'm just wondering how steady my heart rate should be over my 15 minute interval? I can keep it within a 15 bpm range over that period but not much tighter than that. Is that reasonable? Should I be focusing more on keeping it in a narrower band than that?


  • imposter2.0
    imposter2.0 Posts: 12,028
    What intensity are these 15min intervals at? HR will inevitably vary during an interval, and is not a good indicator of effort at higher intensities.
  • I hate to say this but it probably depends on a few things. Terrain, concentration, experience of the effort, fatigue, temperature etc etc.

    Over time you'll certainly become better at holding a steady effort during an interval and with that your HR will vary less. 15bpm isn't too bad but it's not difficult to keep it within 5bpm without having to concentrate and become OCD about it. With practice you'll start to be able to relate your effort to HR by feel and you'll naturally ease up a bit on hills so you're not inadvertently increasing your effort, likewise on downhills you can keep the effort up rather than easing up which most people do.

    I'd also say, in the scheme of things it probably doesn't matter too much if it varies by 15bpm if as long as you're trying to target the appropriate HR level, and speynd 'most' of the effort in that zone, and that the sensations are appropriate to that zone. Spikes are fine. As above tho', beware at higher intensities HR become harder to use as a gauge.

    Don't obsess it, it'll come. The key is you've started to structure some training.
  • Heart rate may vary a lot while adjusting to a new effort. For example if you suddenly start riding at threshold, it could take a little bit to get from the resting/endurance HR to the threshold HR, which could be 30-40bpm higher, however once settled, the HR should ideally remain relatively steady.

    I tend to find my HR gets to a steady 190 or so while riding at threshold, then slowly creeps up to high 190s after riding an effort as I start to fatigue.

    This is a graph for a steady-state sweetspot interval I did the other day. Granted I am targetting power in this instance, however when riding endurance, I tend to relax a bit more and just focus on keeping HR in Zone 2, which means I don't tend to look at it as much. This was the second interval in a session and I was carrying a fair bit of fatigue from the previous weeks training, which can also affect the speed at which the HR creeps up.

    I start the effort at my high Z2 HR of around 155, and after 2 minutes, it has roughly stabalised around 182, which is low Zone 4 for me. After this, while retaining a similar effort, the HR does slowly drift up towards 191bpm over the course of the 20 minute interval.
    When maintaining power, the HR stays within a very tight band, around 2-3bpm. It does drift up in a few places though that is often the result of increasing the power for a bit(maintaining momentum over a little bump). Generally, if you keep your effort very steady, HR should stay stable, though it will drift throughout a longer interval.

    So yeah, for me, the actual range once the heart rate has adjusted is 182-191bpm, however if I did compare against the very start, it would be a bigger gap. If your HR is very variable during your effort, its probably indicative that you are adjusting the pace too much, going easy then going too hard, rather than keeping nice and steady. If it drifts slowly up over the course of the interval, that is common.

    One technique I found useful for keeping my power consistent, even without a power reading to stare at was to focus on really relaxing my legs. Still pushing out force, but not so much tensing the legs on each push but relaxing them and letting them consistently spin. It can help give you a better perception of the small force changes you are putting through the pedals and helps you find a pace that is nice to sit at.
  • fenix
    fenix Posts: 5,437
    Depends where you're riding. If on a turbo then you should be able to control it with more precision - fatigue excepted.

    Out on the road - with wind, terrain and traffic to contend with - it will be a lot harder to keep it within a narrow band.