Why is my heart rate lower on an indoor trainer?

[superclimber]

That's why I said with the same power.

Another point to consider is perceived effort. There is no one to race against when you are indoors. If someone is getting away from you in a race, or it is your turn on the front and you don't want to slow the pace, you can often summon a little more effort than would be possible in the non-competitive situation of the trainer.

and that's why i apologised. one too many beers and along week. good point though as i explained just after my little faux pas.

 

[mitosis]

i've no idea how you would alter your muscle group usage between the road and indoors (except when e.g., standing which occurs less frequently indoors) and have no idea how the EPs could have come to such a conclusion. At a given power output my HR is generally lower indoors, or i can produce a significantly greater power indoors compared to outdoors at the same HR (not that i train by prescribing a HR).

We can't say why the original posters HR is different, and there are so many confounding issues without any good data (power output).

ric

Its not just the original posters heart rate that is lower for the same perceived effort on the trainer. Its the norm and accepted as such - at least around here.

Cyclists I have worked (and raced) with consistently report a lower heart rate at maximal exertion on an indoor trainer (except for rollers where upper body is needed for balance) than at the same point on the road.

 

[hotlipsmc]

At a given power output my HR is generally lower indoors, or i can produce a significantly greater power indoors compared to outdoors at the same HR

How do you measure your power output, and is it the same for on the trainer and on the road?

 

[ric_stern/RST]

Its not just the original posters heart rate that is lower for the same perceived effort on the trainer. Its the norm and accepted as such - at least around here.

Cyclists I have worked (and raced) with consistently report a lower heart rate at maximal exertion on an indoor trainer (except for rollers where upper body is needed for balance) than at the same point on the road.

Unless you can compare your *power output* directly indoors and out, you may very well not be riding at the same intensity. however, i have reported that my HR is sometimes lower indoors.

Your HR could be lower indoors simply due to the monotonic power output, whereas outdoors it can be higher due to the constant changes in power and the additional stress that causes.

however, your HR at a given power can be *higher* indoors due to the poorer cooling afforded by e.g., an electric fan compared to air moving over your body. This causes an increase in core temp and can lead to cardiac drift and overheating.

ric

 

[ric_stern/RST]

At a given power output my HR is generally lower indoors, or i can produce a significantly greater power indoors compared to outdoors at the same HR

How do you measure your power output, and is it the same for on the trainer and on the road?

Generally with a Power Tap. As quoted above i can produce higher average powers indoors (over long periods of time).

ric

 

[mitosis]

Unless you can compare your *power output* directly indoors and out, you may very well not be riding at the same intensity. however, i have reported that my HR is sometimes lower indoors.

Your HR could be lower indoors simply due to the monotonic power output, whereas outdoors it can be higher due to the constant changes in power and the additional stress that causes.

however, your HR at a given power can be *higher* indoors due to the poorer cooling afforded by e.g., an electric fan compared to air moving over your body. This causes an increase in core temp and can lead to cardiac drift and overheating.

ric

I agree with you. Most people around here only use the trainer as a last resort or for specialised routine - they use fans and train when it is cool.

The comparisons I am refering to are for athletes at maximal effort on the bike and on the trainer - and taking into account factors such as body heat.

At maximal effort (given similar amounts of fatigue) I believe I am making a fair comparison.

 

[davidbod]

I experience the same "problem". I discussed it with two exersice physiologists, and we came to the conclusion that it had to be related to number of muscle groups you are using on the trainer vs road.

We assumed that your heart rate relfects total body power output, from all muscle groups. We also assumed that the more you extert a specific muscle group, the more it hurts.

Looking at the trainer, it isolates many of your muscle groups, and concentrates the effort into your thighs, specifically the quads. So for a given power output (heart rate), you are going to hurt more and fatigue quicker because the load is being disproportionately carried. By contast on the road, you will utilise your hamstrings, calves, occasionally upper body as well as adjust positions, all of which push your heart rate up and spread out the total work load.

I think hotlipsmc is on to the right track here. I find that indoors on a trainer I get a much more concentrated burn in specific areas of my thighs due to the trainer isolating specific muscles. This then equates to a percieved effort greater to that on a bike outdoors, when in actuality it is not, as the HR data indicates.

 

[ric_stern/RST]

I think hotlipsmc is on to the right track here. I find that indoors on a trainer I get a much more concentrated burn in specific areas of my thighs due to the trainer isolating specific muscles. This then equates to a percieved effort greater to that on a bike outdoors, when in actuality it is not, as the HR data indicates.

To put it another way HR is a "red herring" if you can't compare identical power outputs

ric

 

[bikeguy2]

Hm.. I always sweat way more and get hotter indoors.. there's no air blowing across your body at 40 km/hr indoors unless you have some big fans blowing. I suspect my heart rate is higher indoors than outside actually riding. Once I get a polar HR monitor I'll be able to determine that.

-Bikeguy

 

[ric_stern/RST]

I suspect my heart rate is higher indoors than outside actually riding. Once I get a polar HR monitor I'll be able to determine that.

-Bikeguy

ultimately, this will prove very difficult to do, if you don't have a power meter -- as you won't be able to get the conditions identical between indoors and out

ric

 

[bikeguy2]

Ric, indeed even with a power meter it would be perhaps difficult to account for accelerations and gear changing in riding outdoors. Ideally, the run outdoors would need to be at a constant power and gear with little
wind to keep fluctuations in power output minimal.

Also keep in mind, mechanically braked ergometers frequently show lower power outputs than the true value or that would be reported by an SRM. Electromagnetically braked ergometers are more accurate.

 

[ric_stern/RST]

Also keep in mind, mechanically braked ergometers frequently show lower power outputs than the true value or that would be reported by an SRM. Electromagnetically braked ergometers are more accurate.

which is why i said power meters (i.e., Power Tap, SRM) otherwise i would have said a mechanically or electromag braked ergometer!

ric

 

[bikeguy2]

which is why i said power meters (i.e., Power Tap, SRM) otherwise i would have said a mechanically or electromag braked ergometer!

ric

The point was directed to the original poster or anybody else not aware that mechanically braked ergs are off a good few percent lower. If you are aware, then no need to comment.

 

[mitosis]

which is why i said power meters (i.e., Power Tap, SRM) otherwise i would have said a mechanically or electromag braked ergometer!

ric

The point was directed to the original poster or anybody else not aware that mechanically braked ergs are off a good few percent lower. If you are aware, then no need to comment.

But maximum power is maximum power, on the road or off, in the wind or out of it, on a trainer or on the road.

 

[tomUK]

FWIW, I think the mind is often neglected in training.

When life is good, you feel good. Equally when you feel good, life is good.

I too have a lower HR on my indoor trainer. More importantly for the same power output my PE is higher indoor than outdoors. Normally I train with a large fan in front of me and also have all the windows in the house open as to create a draft.

It has come to the point now where I detest training indoors. It just feels too hard for the power I give out compare to riding on the road.

To be honest, I believe that the reason it feels harder is due to the bordem factor. Training indoors is boring (even if I listen to music or watch a DVD) and therefore I draw the conclusion that if something is dull it will infact be harder to achieve.