# Cycling/Running comparison.

Discussion in 'Training, Fitness and Health' started by Andy in Sig, 31 Mar 2008.

1. ### Andy in SigVice President in Exile

I'm fairly sure that there is no simple answer to this query but here goes anyway: is there some simple rule of thumb or formual where you can say x miles of cycling = y miles of running and vice versa?

I ask this because I've been doing a bit of running with a view to possibly doing a half marathon and extending the running distance, while doable, is a much more gradual process than extending cycling distances e.g. I can extend my long bike run in, say, 25 km stages but my running in about 3 - 5 km stages.

Does for instance my Sunday bike run of 100 km in about 5 hrs equate to a half marathon in two hours?

2. ### john59Guru

Location:
Wirral
http://davesbikeblog.blogspot.com/2007/09/running-vs-cycling-burning-calories.html

John

3. OP

### Andy in SigVice President in Exile

Thanks John. Even I can get my head round that. I shall now start calculating.

4. ### BlueLegendary Member

Location:
Cyprus
I'm not a scientist, but I find it hard to believe the assertion that when running the calorie burn doesn't increase with effort. Also, the assertion that headwind makes no difference to runners is unreal.

I used to run long distance races at what could be called 'club' level and headwind and effort made just as much difference as when on the bike - it sapped energy (cals)!!

20-30 years ago I saw a suggestion that 1 mile running was worth 4 miles cycling as far as effort is concerned - which ties in with the overall assertion. However, one has to be mindful that different muscle groups are used in the sports. My marathon times were better than LA, but I couldn't even have kept his dust trail in sight on a bike!!

5. ### Twenty InchNew Member

Location:
Behind a desk
As blue says, different muscle groups are used in the two sports. If you try to train for a half-marathon by cycling an effort-and-calorie-equivalent distance, you'll blow up after about 5 miles into your actual half-marathon.

Ask any triathlete what the bike-to-run transition is like. It feels like you've got the wrong legs on. As a result, all serious triathletes (not that I was one), will do plenty of back-to-back training - off the bike and out immediately for a run.

Best way to train for a half-marathon is to run. Your long runs should be about 8 miles long, and faster ones at 6 miles. If you can cover 8 miles easily, you can do the half. If you can cover 6 miles easily, you'll probably do the half, but less comfortably. You should do one long 13 mile run about 1 month before the event, just so that you know you can handle the distance. Make it as slow as you like, even at a "run 5 mins, walk 1 min" rhythm, but it's worth doing to build your confidence. Let us know how you get on.

6. ### Disgruntled GoatNew Member

Personally, I'd say a run is equivalent to a fifth of a bike ride

125 cycle = 25 run

But it all depends on terrain. Most marathons are flatish but most sportives are hilly so the ratio might have to be adjusted to 1 to 4.

As for speed - can't help yer there. some people are better at running than cycling and vice versa. Plus you can't train for running by cycling other than maintaining aerobic output.

7. OP

### Andy in SigVice President in Exile

Twenty Inch,

I'm up to 11 miles on the running without any problems. My cunning master plan is to get up to half marathon plus one mile so that psychologically I should have a relatively easy time. The question was more about simply trying to equate fitness levels.

The thing is, in 2006 I did 200 km in a day on three occasions on the bike and felt fine afterwards. I couldn't imagine doing a marathon without feeling completley knackered.

8. ### Twenty InchNew Member

Location:
Behind a desk
Andy

Doesn´t sound like you need to worry about your fitness then!

9. OP

### Andy in SigVice President in Exile

I'm not sure. I think my stamina is OK but I will be chuffed if I do the half marathon in under two hours. On top of that I reckon I could do with losing a stone of flab.

10. ### CushVeteran

How would a 100 mile challange walk to be completed in under 48 hrs compare with a 100 cycle ride to be completed in 14hrs or under.

11. ### yenrodGuest

I used to work on the comparison of;

15mins RUN = 20mls ride.

30mins RUN = 1hr.30min ride.

60mins RUN = 2-3hr ride.

12. OP

### Andy in SigVice President in Exile

That's interesting Yenners, especially the last figure. Taking a sort of consensus of all the replies, in terms of distance it seems to be about 5:1 cycling to running, so 100 km on the bike (say 4.5 - 5.0 hrs depending on wind direction) = roughly a half marathon (say 2 hrs).

I suppose the only way to get a real answer is to get hooked up to loads of machines and get individually measured.

13. ### yenrodGuest

Andy, I came to this conclusion via practice ie when id do a run it'd feel like a 20ml'er etc..

14. ### Stig-OT-DumpVeteran

Andy
I think it all depends on what you are comparing between the 2 activities.

The answers so far seem to be solely concerned with calorie balance, which is alright for working out how much exercise to do to lose the flab but might not address other things - like lactate threshold etc.

A good long cycle might be good for recruiting slow twitch muscles and training your body to use fat for fuel and save glycogen, but you will be using different muscles when running.

You should maybe consider using your existing rides to do training based around heart rate zones and using it to supplement runs and maybe replacing a run per week. I reckon you should still try to do 3 runs per week, and make one long and slow for now (below aerobic heart rate), cranking it up a few weeks before a half-marathon.

There are some good training programmes (just for running) available online - based around 10 weeks of training - e.g. http://www.runglasgow.org/senior/prepare/prepare.php

I'd imagine that if you are able to replicate your planned running heart rate for your guestimated race duration you'd be doing pretty well.

Stig

15. ### andygatesNew Member

My personal rule is that a half-marathon - 13 miles - is about as tough as a century ride. So that's about 8:1, give or take. Both take the same sort of time to recover from, and it scales down to about half those distances: a 10k and a Sunday 40 are about as tough. That's all at a steady, trundly sort of pace.

More intense runs, and more intense rides, are a whole different thing.

And I'm not factoring in the silly injuries I get when running...