Indoor vs. Outdoor Miles

I am curious as to the general feeling(s) and perception(s) around indoor (or virtual) vs. outdoor miles.

While obviously different, is one environment better than the other? Do hours spent in the virtual saddle count as true time on the bike? Should cyclists disregard virtual hours when compared to those on the road/trail?

This is intended to look beyond the “fun factor” of riding (where, IMO, outdoor will always prevail), but instead at the existing perception(s) among cyclists who ride indoors, outdoors or both.

Hmm, a question I never asked myself. I just don’t think one is better than the other, I consider them to be equally good.

Me personally, I train better indoors. I like the comfort of having Sufferfest, err Systm, hit me with a structured workout. I just can’t do structured workouts outside. Either it’s the traffic, the routes available, or my own laziness wrt focussing on the workout.

Riding outdoors, on the other hand, is about riding for me. I like the exertion, being outside, away from the big city.

Not better, but the other side of the coin. Both have their merits.


It depends on what type of indoor riding you are doing. If you are riding in virtual worlds that have lots of coasting on downhills, (and stoplights :slight_smile: ) then this is different that structured training sessions.
There is likely a meaningful distinction between indoor ‘riding’, and indoor ‘training’, just like there is outdoors. I don’t think ‘indoor miles’ are a good way of measuring training volume - I think ‘hours’ is better to measure, both indoors and out. I think the ‘miles vs. hours’ is often also a difference in people who tracking training vs tracking riding. One isn’t better or more valid than they other, but they are different things. I don’t see any recent, serious discussion of cycling training volume that describes distance ridden - it is all about hours. Miles are not a measure of something physiologically, but hours are.

I find indoor training to be much more effective for a given amount of time, as there are no stoplights, etc, and I am able ride 2 hours straight without a break. For me, this makes 2 hours of indoor training time on the bike a much, much better working than 2 hours training time outdoors.
Some people have great training roads 5 minutes from their front door, so the difference won’t be as big, but I think that is an exceptional case.

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I ride 99% of the time outside and don’t care too much what others do, I have friends that only do group rides on the flat lands and so they ride the same as me but in a fraction of the time, who am I to say that isn’t “real”. Zwift inflates miles and elevation a bit, TR deflates miles in my experience, I’ve never really felt that doing big climbs on a trainer really simulates big climbs accurately since you don’t have the decreasing Oxygen density that you do IRL and getting out of the saddle is so unnatural feeling on the trainer. I’ve always used hours anyways, trainer is the bomb though if you sleep in on a 117 degree day and need to do V02 efforts.

The group rides are usually BS #s, I see guys averaging 28 mph on those things and they get dropped from the B ride in the real world.

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IMO… it comes down to two things. Fitness and skill.

For developing fitness, indoor miles can be even more effective (minute for minute) than outdoor rides since you eliminate the stop and go of traffic or street design limiting your training efforts. You can spend an hour and have that entire hour dedicated to actual training with zero minutes lost coasting down hills or rolling up to stop signs or cutting an interval short because of traffic or whatever else.

But the rise of Zwift has also been responsible for a rise in wildly incompetent bike handlers, at least in my area. I’ve never seen so many people on the roads that can’t hold a line or who just have no finesse in handling a bike… look over their shoulder to check traffic and swerve three feet over or try to ride with no hands and wind up weaving back and forth wildly, barely in control.

So… While I hate riding indoors, there’s room for both. Indoor is great for time condensed workouts focused on developing strength but it doesn’t replace or replicate actually riding. Riding can give you strength and skill but comes with some environmental complications that can be a pain. In terms of ‘fun factor’ though, I get zero joy from riding indoors.


My experience:
Indoor much more consistent effort/time. One hour riding at 75% is worth about 1.5 hours outdoors. I ride down descents. I might have 0 power for 1 minute out of the 60 minutes because I don’t coast, etc.
Outdoors My peak efforts are higher–on a trainer if I let up and go very slowly on a steep section, I just pedal with less power. On the road, I can’t go that slow, and my competitive nature comes out, so I end up with a burst of power I never get indoors.

I mostly ride hard indoors, train once a week, so to speak, and only ride outdoors, never train.

BTW, for those who ride indoors, I highly recommend Rouvy. I hated indoor riding until Rouvy. It is just glorious to be riding around a sunny, mountainous lake in Northern Italy when it is snowing outside.


This is precisely correct.

Indoor workouts are (all things being equal) better for making you fitter. Outdoor workouts are better for improving you as a bike rider.

The only exception, I think, is long threshold intervals, where cooling/heat stress on the trainer becomes quite problematic to manage, so if you do have access to straight-ish, flat-ish roads without too much traffic and minimal junctions, that’s where to do 2x20 etc. I’m fortunate to have access to 1 such road: about 14km, gently undulating, no sharp bends, and only 2 mini-roundabouts. I find really hard efforts on that route much easier (physically and psychologically) than on a turbo.

Erg mode is also over-used, but that’s probably a tangent.


Depending on your indoor set-up trainer riding can be anywhere from way easier to way harder than IRL riding for the same miles or hours. So instead of indoor versus outdoor miles and hours, try thinking about effort. Outside of easy, just spin the legs days, training is composed of riding to certain levels of effort. And you can ride to the same levels of effort outside or inside.

A thing about inside though, the fixed position of a bike in a trainer and instability (against lifting) of even the heaviest trainers, can really hurt some people’s top-end and max power generation. So exercises like big gear max acceleration from rest and max effort sprints don’t really work for some riders indoors because they can’t replicate the max IRL effort. But it’s typically not an indoors issue if you don’t use large amounts of body leverage IRL.

That is enitely dependent on your gear choice…TR calculates “mileage” simply based on flywheel revolutions. If you throw it into your 53x11, you’ll get grossly inflated numbers…if you have it in your small ring, you’ll get lower-than-expected numbers.

Big ring, upper-middle cassette will get you semi-realistic numbers (at least vs. a 20mph avg on the road, which I kinda use as a benchmark)

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I completely agree. My time indoors is very pragmatic…it’s purposeful and intended to improve my fitness in a very controlled environment.

Most often, training = indoors, riding = outdoors.


While I have an indoor trainer, and rower, of course I don’t count that as riding, but simply exercise, or conditioning. All good, of course, and one feeds the other, but just as video games of F1 racing (or whatever) are not actual racing, so is indoor training not actual riding. I keep daily stats of my outdoor miles/kilometers, but do not add in any indoor info–I had 15,000 km on the year last year, outdoors. The weather would have to be absolutely horrendous for me not to ride outside–last year I missed 10 days total, a few due to a bout with shingles, and the rest due to torrential downpour, and/or hurricane/typhoon level winds–otherwise, I ride in the rain, wind, heat, snow, or whatever.

I think that indoor miles result in a better level of fitness as a result. There’s less cruising time, you don’t need to stop pedalling and pull on the brakes because you’re riding downhill towards a stop light.

That said, outdoor riding results in better bike handling skills. I knew one cyclist who did all his riding indoors and then came out for a ride and struggled to navigate tight and twisty corners.

In short, both have advantages.


I’ve found Indoor vs outdoors utilises slightly different muscle groups and firing patterns, whilst indoor training is great for building fitness I find I need a period of adaption to apply those gains to outdoor. I’m in the UK though so the bulk of my indoor riding is heavily biased to the winter though -I try and do most of my spring / summer sessions outdoors.

There’s no doubt that you can put yourself into the hurt box a lot faster indoor than out. I do a lot of indoor riding in the winter here in Minnesota, but I mostly hate it, and find the best approach is simply to do hard structured intervals for an hour, and then get off. I do my long work on the fat bike, and 1 hour indoors 3 or 4 times per week seems to keep me fit enough to continue to haul that behemoth around for 4-5 hours in the cold and snow.

Not sure whether that’s really due to Zwift. Roadbikes seem to be the thing at the moment (at least here) and the result are loads of people who can barely grip the tops and sport cadences of 60 rpm. They’d be better served with a different kind of bike, but that isn’t as “cool”.

In all fairness though, those that stick with the sport and put effort into it will develop better handling skills. We all started somewhere.

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I agree that it might be a complex thing…however, virtual riding can (and does) potentially give new riders a false sense of confidence. They know the mechanics of turning over their pedals, but not how to safely, confidently and capably handle their bike.

The differences between riding as imagined (indoor/virtual) vs. riding as actually done (outdoors) is striking. You can develop infinite fitness (and maybe ego) inside, yet be a neophyte rider in the real world…when put together, I’ve seen this result in a complete breakdown in safety between the individual rider, those riding beside him, and other vehicles on the road.

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Yeah… a lot of guys think they ride 6 hours a week cause they do an hour on Zwift after work but only spend an hour or two on the road each month. They develop the idea that they ride a bike a lot and an assumption that means they know what they’re doing when, in reality, they just ride an exercise bike a lot and have no idea what they’re doing.

This is interesting. I had no idea. I couldn’t care less how many “miles” it was telling me I had ridden indoors, but I did think the numbers seems a little low for the effort level. I’m riding in the small ring, ERG mode.

More power to you if you can ride for long periods in ERG mode. I hate it. Hate it. Hate it.

I do intervals on Rouvy on regular routes using the resistance of the route. Then again, I’m not doing hardcore training.

My Cycleops is on the back deck, so technically, my “indoor” miles take place outdoors.

I’ll only ride on the trainer when going for a proper ride out of the house isn’t an option, be it due to time, work, family constraints etc.

That said, from a pure workout perspective, I am a lot more sweaty and tired after 45 minutes on the trainer set to a specific workout than I am after 2 hours in the hills.