Cycling distance equivalent to running a marathon?

[Lycra Man]

Dear Panel,

I used to run a bit before I returned to cycling in 2002. If you mentioned a marathon, or half-marathon,  most people knew the scale of the endeavour, even if they didn't know the precise distance.

What do you think is the cycling distance equal to a marathon?

My calculation is based on elapsed time. So 3.5 hours for a marathon x 4 (because running expends 4 times the calories of cycling) = 14 hours. At - say - 13 mph that's 182 miles.

So would it be a double century?

Does anyone else have a view on this. Am I talking (OK writing) rubbish again?

Lycra Man

[mrcharly-YHT]

I'd say that's about right.

[tom_e]

I've only done a half-marathon, but calling that ~100miles does sound vaguely reasonable.

(well, as good as you'd get when the two activities feel quite different to me)

[Malandro]

I've often wondered this myself.

I've run one marathon (4 hrs 25 mins), more or less without stopping, and once the euphoria of finishing had worn off I was a bit of a mess.  I doubt I'd have been able to run much further.  

The most I've cycled in one go is a 200 km audax so there were a few stops involved.  I was fairly knackered after but I could both walk and think straight and could probably have cycled a bit further.

200 miles therfore sounds about right to me.

[Justin(e)]

Very subjective, but for me I reckon that it is about a 600km.

A double century is relatively easy to follow up with another double the next day.  I always found 200km relatively easy and I found 1/2 marathons relatively easy.

When I used to do both, the marathon was the culmination of a lot of training, and ditto for a 600.

[iakobski]

You're in the right ballpark. It's complicated because when you run, a lot of energy is expended keeping your body off the ground, so even if you're running slowly you use quite a lot of energy. You can cycle really slowly and use hardly any energy at all. OTOH, as you cycle fast the wind resistance has a much greater effect.

According to a quick gooooogle, a 180 lb person uses ~3500 kCal per marathon.

Checking the Bicycle speed & power calculator, this is about the same as 170 miles at 13 mph - which matches your estimate.

In audax units, it is also roughly the equivalent to an eight-hour 200k, or a 26-hour 400k

[CommuteTooFar]

25 years ago (when I was young) I ordered a book from a bookshop in Central Cardiff. A card pops through the letter box So I walk the six or so miles to the bookshop. Discover volume 2 is more expensive than volume 3, I do not have enough Money. Walk home borrow the difference from my brother walk back into town acquire book walk home. I have my tea.  A Marathon was done, no preparation, no plan just done. I have never ridden 200km without intention.  So we can conclude leisurely speed Marathons are much easier than 200km bike rides.

At more ambitious speeds pain will vary.

[simonp]

Dear Panel,

I used to run a bit before I returned to cycling in 2002. If you mentioned a marathon, or half-marathon,  most people knew the scale of the endeavour, even if they didn't know the preise distance.

What do you think is the cycling distance equal to a marathon?

My calculation is based on elapsed time. So 3.5 hours for a marathon x 4 (because running expends 4 times the calories of cycling) = 14 hours. At - say - 13 mph that's 182 miles.

So would it be a double century?

Does anyone else have a view on this. Am I talking (OK writing) rubbish again?

Lycra Man

Hmm, you're multiplying time by 4 but the 4:1 ratio is distance not time - you will burn around the same number of calories per hour - so you're probably out by a factor of 2 on a calorie basis.  100 miles should be about the same calorie burn as running a marathon.  Whether that's a reasonable comparison is a different issue.  Running puts a lot more strain on my body than cycling, I find.

[iakobski]

Very subjective, but for me I reckon that it is about a 600km.

I can't run, so a 1 km run would leave me in much the same condition as a hilly 600
 

[scottlington]

It's far to subjective imo. Note sure you can accurately compare the two. I have completed 2 x SR in the last two AUK seasons and LEL last year. However, ask me to run even a couple of miles and I SERIOUSLY doubt I could do it.

Some people can run, some can cycle, some can do both quite happily. For me, completing a marathon would be far far harder than anything I've attempted on a bike, but that's not to say another person's perception is the polar opposite.

[border-rider]

that's the point

If I've been training for it, a 10 k run is trivial.  If I haven't it's an impossibility

100 k on the bike is not a problem, but an 8 hour 200 might be without training

[Karla]

As a rule of thumb, I'd probably say 100 miles to 200km cycling equals a marathon, giving a rough 1:4 ratio. 

Whoever said a 26 hour 400km audax could be compared to a marathon, I don't see that you can slow things down and increase distance and still compare the two.  Once you're riding for 26 hours, nutrition and sleep deprivation give whole new aspects to the exertion.

[MSeries]

What do you think is the cycling distance equal to a marathon?

26.2 miles. It's the same distance whether you ride it or run it.n  

[iakobski]

As a rule of thumb, I'd probably say 100 miles to 200km cycling equals a marathon, giving a rough 1:4 ratio. 

Whoever said a 26 hour 400km audax could be compared to a marathon, I don't see that you can slow things down and increase distance and still compare the two.  Once you're riding for 26 hours, nutrition and sleep deprivation give whole new aspects to the exertion.

That was me, and I was basing it solely on calorie expenditure.

The point was that if you cycle fairly slowly 15 km/h you have to cycle a LOT further to expend the same energy - the same is not true for running.

[urban_biker]

As a rule of thumb, I'd probably say 100 miles to 200km cycling equals a marathon, giving a rough 1:4 ratio. 

Whoever said a 26 hour 400km audax could be compared to a marathon, I don't see that you can slow things down and increase distance and still compare the two.  Once you're riding for 26 hours, nutrition and sleep deprivation give whole new aspects to the exertion.

That was me, and I was basing it solely on calorie expenditure.

The point was that if you cycle fairly slowly 15 km/h you have to cycle a LOT further to expend the same energy - the same is not true for running.

But if you compare hours of pain you get to squeeze a lot more of those into a 400k audax  24ish hours vs 5/6 hours + on a marathon.

[Tewdric]

I think about 300Km of undulating audax type riding is about as close as you'll get, but there's no direct comparison and, as Mal Volio says, training has a big effect of te subjective experience of either.  Running for a long time has a much more debilitating effect thatn cycling too and I think there's a point at which the miles run / knackeredness curve starts to get steeper than the cycling equivalent.  If you keep eating and drinking, you can keep on cycling for days, that's not the case with running IME.

FWIW I found Ironman UK to be abut the same subjective effort as a Brevet Cymru 400, but you get knackered in a different way.

[valkyrie]

From my limited experience (I've only done one marathon) I reckon about 150km of cycling at 25kmh gives a similar feeling of tiredness to running a marathon in about 4 hours. The big advantage of cycling is that you can walk down stairs normally the next day. Comparing a marathon to longer distance rides is just daft - after all running a marathon is just jogging all morning. You get home have a shower and a bit of lunch then do normal stuff for the rest of the day. When I get home from doing a 600 I get showered and crawl into bed.

[iakobski]

From my limited experience (I've only done one marathon) I reckon about 150km of cycling at 25kmh gives a similar feeling of tiredness to running a marathon in about 4 hours. The big advantage of cycling is that you can walk down stairs normally the next day. Comparing a marathon to longer distance rides is just daft - after all running a marathon is just jogging all morning. You get home have a shower and a bit of lunch then do normal stuff for the rest of the day. When I get home from doing a 600 I get showered and crawl into bed.

Interesting comments - after my last 600 I cycled home, then cycled to work @ 6am the next morning. But I DEFINITELY could not walk down stairs normally 

[Jord]

As a converted runner I know a lot of serious runners who compete in fell races and regular marathon runners who also cycle a bit - most can't comprehend cycling 200K!

As one who has also done both I'd find it very very hard to compare - running really beats you up where as cycling doesn't but the tiredness is the same.

I also find running is something you have to keep doing - even a weeks break and you feel a wreck!

Now as far as (none crashing!) injury's are concerned cycling is so much easier on your body  

For my own training log I class 1 mile of running as equal to 10K on the bike. So 260K.

[inc]

There are too many factors for any meaningful comparisons. For example a decent club runner can run at 6 min mile pace or 10 miles in an hour, a decent club cyclist could do 25 miles in that  time which is a factor of 2.5 As soon as the cycling pace slows it becomes far more advantageous over running. Not very scientific but you could see what your pulse rate is at your marathon speed and compare that with your bike speed at the same HR and then multiply your bike speed by your marathon time.

[eck]

It may be an urban myth, but weren't triathlons invented in an attempt compare running a marathon with cycling and swimming "equivalent" distances? 

[mattc]

IFF it were possible to make a comparison, I think you should be looking at flattish courses e.g. the Mersey 24H, or 12H courses (which I'm not familiar with).

Most Audaxes use "interesting" routes, whereas most marathon courses are pretty flat.

(The average speeds - even for the likes of me - on the Mersey 24h are far higher than an Audax taking around 24hours. But more relevant is that your speed is much more constant, and you can keep your heart-rate under control - this is much harder on typical Audax hills.)

[mrcharly-YHT]

IME, the limitation on marathons isn't heart rate, it's durability of tendons and joints. OK, for elite youngsters, they might be able to run on the anaerobic edge, but my tendons and shins give up before then.

So a half marathon, without training, is perfectly possible, but you'll be in a lot of pain and only just making it (running all the way). A full marathon? Not possible imo

Cycling doesn't have similar stresses, its much easier on the body. I think the limitation is part mental, part system-energy (how long can you go on riding before exhaustion stops you). 

I think a 100miles, without training, is possible. 200miles? Probably not.

[Sigurd Mudtracker]

I go for a 4:1 cycling to running ratio.  I've been doing both all my life but concentrate far more on the running competitively - cycling is a fun, cross-training  alternative to running as well as a short distance transport option.  I find it much easier to go out and run 14 miles than run cycle 60 but I think that's training effect for you.  I'm planning on riding a hilly 85 mile ride later in the spring which will be the furtherest I've ever ridden and it's got me worried - the previous record was 75 when I was a youth, 20 years ago.  But I had run 10 miles earlier that morning...

[andygates]

I go with the consensus that 100 miles = half-marathon, but I bailed on my marathon and I'm not daft enough to ride super-long...