plantrob

Got to play with my new heart rate gadget for the first time this morning (my wife's been very good to me ). Before this, the only time I'd get a sense for my heart rate was on my bad-weather workouts on electronic bikes at the fitness center. On those bikes, what feels like a pretty hard effort yields me about 150 bpm, which I find difficult to sustain for more than 10 minutes or so. Really pushing it gets me up to the vicinity of 170 bpm, but only for a minute or two before I give up, huffing and puffing and legs like putty.
So I was really surprised that on today's ride, my average heart rate was upwards of 160 bpm for the 1 1/2 hours or so I was riding solo (slightly lower during the slow part of the group ride I joined up with, and right back to 160+ for the fast part). On harder efforts, like the two climbs early on in the ride, I spiked to just over 180, with rates over 170 sustained for about 20 minutes.
Now, I would have expected that the greater enjoyment and better cooling (especially at temperatures around freezing!) of an outside ride would allow me to push a little harder - but the difference between outdoor and indoor results was much larger than I anticipated, and really makes me wonder if I'm getting as much training benefit out of those indoor workouts as I'd hoped. Is this common experience?

wkg

My HR is usually 10-20 BPM lower for a given perceived effort level indoors.

dnuzzomueller

Likewise. Although I would guess this has something to do with oxygen supply. When you are outdoors you really do get a fresh supply of air unlike on a trainer.

jrobe

If your HR is lower inside it is because you are not working as hard. There is no magic here.

plantrob

Well sure, that's what I assumed too. But the wall I hit on the inside bike at heart rates that feel not too hard when rolling outdoors made me wonder. Does overheating cause a lower heart rate at equivalent power output? The puddle that forms underneath me on my indoor spins certainly attests to over-active heat management on my body's part... From the other replies above, I take it I'm not the only one having a hard time getting heart rate up on a spin bike.

svtmike

Point a big fan at yourself if you can. If you were running a power meter, you'd find that your power output is down too.

Trakhak

Many people use fairly high resistance settings for indoor exercisers but spin reasonably low gears out on the road. In my experience, spinning a low gear at a high cadence gets your heart rate higher than pushing a high gear at a lower cadence.

revchuck 

There's way too little info here to work with. First, you're dealing with two different HR monitors, so there could be a bit of difference due to that. HR is influenced by hydration level; lots of folks don't drink while on a spin bike, but do on their regular bike. There's also a difference in how hard you're willing to push yourself when you're alone as opposed to when you're riding in a group; most cyclist push themselves harder when in a group setting.

IMO, your HR on the bike outside is more indicative of your HR range than the HR from riding inside.

As to whether your indoor workouts are helping - it sounds like you're just getting on the bike and pedaling. That will help somewhat, but you need to determine your lactate threshold and then do structured training based on that and your goals. Riding indoors sucks, so you might as well make the suck pay off as much as possible.

Beau210

If you used the HRM of the gym bike then the diff. is due to the crappy HRM of that bike and the good one your using outside.

Jsiegs

x2. Keep in mind that there are a myriad of reasons why HR can vary and your intensity is only one of them. So comparing these two rides might not be apples to apples as well. Most people just find it harder to push higher intensities indoors (though they are physiologically capible of doing so).

Although, if your position is significantly different inside to out (I was assuming it was not), there's a chance you're engaging different muscles. The muscles you're engaging inside might be less trained and top out at a lower intensity than the muscles you're engaging while outside on your real bike. Every motion (e.g. cycling vs running in an extreme example) has it's own correlation to HR that you train independently (e.g. your running and biking Thresholds are not related, nor does training one affect the other, except in a completely untrained athlete). SO if you're riding position varies significantly, it could also account for the difference.

hhnngg1

I think wind flow has a big part to do with it.

I have a big fan in front of me that I can't run at max during fall/winter in the garage since it chills the heck out of me after I start sweating. Still, I have a hard time holding a 145HR for more than 30mins indoors without slowing a bit, whereas outdoors I can average 145HR over 2.5 hrs (meaning I'm well over that for over 50% of it, as I don't stop the watch on stoplights, etc.) Don't have a magical explanation, but I do suspect wind flow cooling has to do with it - on the outdoor bike, I'll get evenly distributed flow everywhere, whereas the fan might overcool some parts like my extremities while my core is still a bit overheated (as seen by the sheer volume of sweat.) My garage tends to be about 50-65F in fall/winter (Norcal) so it's not like it's a steam room in there, either.

Either way, I can hold my indoor threshold (60min absolute max avg HR) outdoors for over 2x as long as indoors, so there's definitely something there.

JTGraphics

I can get my HR up just as high in or outdoors you just need to stay on it and work harder.
Its way to easy to give up on a trainer as you can just stop and get off LOL.
High cadence will get your HR up on a trainer, at least for me it does.

gregf83 

For the same power my indoor and outdoor HR are pretty much the same.

tadawdy

As Andy Coggan has said, you shouldn't think of HR and power as directly determining each other. There's really another level of control above both. Decreased central motor drive explains the decrease many people see in power and HR indoors.

hhnngg1

On the slowtwitch.com forums, where a lot of pro (the forum mod Jordan Rapp is one of the top pros in the WORLD and posts regularly) and national-caliber triathletes hang out, replete with powertaps and power charts from their workouts, nearly all of them recommend threshold power testing both indoors and out due to a 10-25 watt difference that they nearly invariably encounter with indoor vs outdoor efforts. And these are guys who do this for a living, and are super serious about their Computrainer / Powertap numbers. They'll geek out for 25 pages of posts about watts/CdA and the real aero impact of a single straw from an aerodrink water bottle, so I doubt they're lying about the real differences between indoor/outdoor.

I know (as well as they do) that in theory, watts are watts, so it really shouldn't matter indoors/out and thus it should all be 'mental', but these guys can HTFU more than any of us and even they come in slightly lower indoors vs outdoors. Thus, they never recommend that you just take your indoor numbers and just slap 'em on outdoors and be prepared to have everything work perfectly even with a Quark powertap. (Those numbers make a huge impact in the world of ironman triathlon racing, where if you overcook the 112 mile bike by even 5 watts on average if you are aggressively racing, your run will suffer. Hence the geeked out-everything these guys do, including a 25 page debate on the aero impact of a friggin' straw.)

The_Cretin

You give them way too much credit. Slowtwitch has been going downhill for sometime now. Most of the knowledgeable people left a long time ago. Now they're becoming a lot like BF.

Again, you're giving them way too much credit.

Really? I thought it was the poor lighting indoors.

wkg

I don't think the argument has anything to do with Slowtwitch. Jordan Rapp is (arguably) one of the best triathletes and has very smart people working for him.

The phenomenon of lower power and heart rate indoors is very well documented and the people here saying "You aren't working as hard" or "Spin a higher cadence" clearly have no idea what they're talking about. I'm spinning the same cadence indoors as out, sometimes higher just because I pay so much more attention to my cadence indoors. And I'm working just as hard. And like I said this is a well documented phenomenon.

And for what it's worth, I'm no triathlete, but the discussions on slowtwitch are usually much more intelligent and reasonable than the discussions on here.

The_Cretin

Sorry, I just find that statement amusing.

I don't think Slowtwitchers have fared any better on this issue. I see just as many threads there where people wonder why riding indoors is harder but no one posts the correct answer, much like here.

One thing I definitely agree with you on is that the effect is real. Not only that but its implications go far beyond simply being annoying or not being able to produce as much power.

This may have been true 4 or 5 years ago but ST has been on a downward trajectory bringing it within striking distance of BF as the forum where all the dumb athletes hang out and cause a stupidity feedback loop.

wkg

Right, and I am very interested in the implications of this. I don't have a winter bike and maybe I'll get one built before winter is over but given my budget probably not. I probably won't be doing any outdoor winter riding. I've seen how so many of the riders who come out strongest at the beginning of the season here are the ones that continued riding outdoors all winter in addition to their indoor trainer sessions.

It's obvious that indoor training on the trainer does some good things. I think that it increases strength in certain ways that outdoor training does not. But the lower heart rate/power for a given perceived effort level is concerning.

gregf83 

If you're riding at a lower power indoors you're not working 'just as hard'.

Lots of people experience lower power indoors due to the lower inertial load of the trainer, lower cooling, lower motivation etc. If you ride consistently on the trainer you can lower or minimize the difference between indoor and outdoor training. Most people don't ride consistently indoors though and head outside as soon as they can.

Jsiegs

i'd tend to agree with this. But I think its important to note that power inside and outside is different than HR inside and outside as well. Power is power is power. HR is not HR is not HR though. and Power is not a direct correlation to HR - lots of other variables. Apple to oranges trying to relate power to HR so be careful.

In my N=1 example, when i added a powermeter and used it inside, all of a sudden my HR was getting up just as high (or higher) than outside. Power is the direct feedback of your intensity where HR/RPE is not. So now that I'm guided by power instead of HR (and RPE), my indoor workouts my HR gets just as high inside as out. I was cheating my indoor workouts going easier, with a lower HR, but they FELT just as hard before I got a PM. Now with the PM guide, my power/HR are pretty similar inside and out, but inside it FEELS a bit harder. I'd have to check, but I think I actually average higher inside now, especially in the winter, since cooling is a big deal when it comes to HR. FWIW, I usually average more time on the trainer than outside over the course of a year.

So while HR inside and out won't necessarily be a direct comparison, there's no reason why they shouldn't be in the same ballpark.

The_Cretin

Yup.

If you adapt to indoor riding, you're un-adapting to outdoor riding. People who have done all their riding indoors (vs. doing as little riding indoors as possible) have reported an incredible lack of form when they venture outside months later.

They would be stronger yet if they did all their riding outdoors and thus didn't maintain adaptations to indoor riding.

There is a great disjoint between power and PE inside. In other words, it hurts a lot more to produce the same amount of power and you often can't sustain it for as long. It is better than doing nothing though.

Power is power and a watt is a watt. I read that a lot when indoor training comes up. Ironically, it's indoor riding that shows us that a watt is not a watt. Indoors, we pay a much higher "price" for each watt we produce. Just because your FTP is, say, 300W outdoors, doesn't mean you'll always be able to produce 300W for an hour in any situation. Would you have the same FTP using a handcycle? Probably not.

Suppose you train your butt off all winter and increase your handcycle FTP from 150W to 200W. Now would your regular bike FTP see a proportional increase from 300W to 400W? No, it's now also 200W because you didn't ride all winter.

Breathegood

This has largley been my experience as well. If my HR is down on the indoor trainer, it's because I'm not pushing as hard. Output is output. I don't need a power meter to tell me that. I find it much easier to regulate HR (at all levels) on the indoor trainer regardless of intended output, although I do tend to maintain a higher cadence and lower gear inside vs. outside. I would add the caveat that temperature/cooling makes a big difference for me. If I don't have my fan on, it's real easy to ramp up the heart rate to beyond sustainable, and I have to back off substantially. With the fan on, I can maintain a higher average HR without the roller coaster effect. I hydrate by the clock (inside and out) rather than by thirst, so I can't really comment on the effect of hydration on HR.

gregf83 

I think you're exaggerating the difference between indoor and outdoor. In my case it's less than 10% and I can get my indoor power up fairly quickly in a couple of weeks training 3-4 times/week.

If someone is losing fitness while training indoors it's more likely due to a fewer hours/wk rather than some intrinsic trait of the indoor trainer.

merlinextraligh

in my experience my HR goes higher indoors for the same perceived effort, and power, particularly in last few intervals. Pretty sure this is due to heart rate drift related to cooling, or lack thereof.

If you're not getting your HR as high indoors as out your not working as hard indoors.

And if you're doing intervals by HR, you often need to go a bit above the prescribed HR in the later intervals to hit the right zone.