Zone 2 on stationary bike

Question

I am currently doing my zone 2 training on a treadmill. To know how to titrate my running speed, I did a VO2Max test at a professional sports center. The upshot was that to get into zone 2 on a treadmill I should run at 7-8.6 km/h and maintain a heart rate of 113-141 bpm.

Now, inspired by Peter Attia's Q&A on zone 2, I said to do a bit of zone 2 heart rate training on a stationary bike.

I rode the bike and noticed that around 2.5 watts per kilo, my leg muscles started to hurt, but my heart rate was low at around 105 bpm on average. This is much lower than what I normally see when I'm near 8.6 km/h on a treadmill (140 bpm).

My questions are:

1. Without a lactic meter, is there any way to convert my treadmill VO2Max result in km/h to stationary bike watts per kilo?
2. Can I still be in zone 2 on a bike even if my heart rate is much lower than the "equivalent" effort on a treadmill?

Answer 1

It's nice that you are inquisitive about incorporating differing kinds of exercise into your coaching routine! it is important to notice that there's no direct conversion between treadmill speed and stationary bike power output, as these 2 varieties of exercise involve totally different muscle teams and energy systems.

It is additionally price noting that pulse is simply one issue to think about once determinant your coaching intensity. different factors like perceived toil, power output, and rating of perceived toil (RPE) also can be helpful indicators of coaching intensity.

In general, it's usually suggested to use a mix of objective (such as pulse and power output) and subjective (such as perceived toil and RPE) measures to see your coaching intensity and make sure that you're performing at the acceptable intensity for your goals.

It is additionally price considering that your pulse could also be lower on a stationary bike compared to a treadmill because of the various muscle teams getting used and therefore the indisputable fact that you're seated instead of standing. this could end in a lower pulse for a given employment on a motorcycle compared to a treadmill.

To determine your coaching intensity on a stationary bike, you will wish to think about employing a combination of objective and subjective measures like pulse, power output, perceived toil, and RPE. it's going to even be useful to consult a {professional certified} fitness professional or medical specialty specialist for steering on the way to effectively incorporate differing kinds of exercise into your coaching routine and confirm the acceptable intensity for your goals.