Why can't runners cycle quickly

[nickyboy]

Why do you think that?

First one - there is loads of analysis that shows that the force exerted through the pedals, even when riding quite hard, is about 200 Newtons (about 20kg). Of course runners experience no resistance but we're still talking about, when cycling, resistance levels which are very low

Second one - as above. How "strong" your legs are has nothing to do with how fast you cycle unless you're a track sprinter. It's all about aerobic capacity as the forces involved are small enough for everyone to exert (that's the 200 Newtons)

Third one - this makes me laugh. If that was really the case why do all professional cyclists maintain what most people would consider a fast cadence? It's because they have worked out that, to cycle as fast as possible for a long time, allowing your aerobic capacity to be the limiter (fast cadence, low forces) rather than leg strength (slow cadence, high forces) gives the best results

 

[nickyboy]

Surely with running if you go uphill you use a shorter stride which is similar to using a lower gear on a bike, cadence remains roughly the same.
A more accurate test would be increasing the resistance in both cases.

Spot on. They should start to incline the treadmill for the runners to provide a similar experience to increasing resistance for the cyclists. Then the runners would start to say "I don't have enough strength in my legs" to keep going....which is nonsense in the same way that saying you don't have enough strength in your legs to keep cycling is nonsense

 

[ayceejay]

I think the author makes a good point when he suggests that we make a mistake in thinking that
pro cyclists spin a low gear at a high cadence when in fact they are spinning a high gear at a
high cadence which is what makes them fast.

 

[ColinJ]

I think the author makes a good point when he suggests that we make a mistake in thinking that
pro cyclists spin a low gear at a high cadence when in fact they are spinning a high gear at a
high cadence which is what makes them fast.

But it isn't 'strength' that lets them do that, it is 'power'.

Olympic weighlifters are incredibly strong but they are unlikely to be fast on a bike!

I once took a younger bodybuilder colleague out for an evening ride over the local hills. He was strong enough to break his chain (mashing a 52/13 gear round on a climb! ), but trying to keep up with me half-killed him. (And I am not fast!)

 

[ayceejay]

But it isn't 'strength' that lets them do that, it is 'power'.

Olympic weighlifters are incredibly strong but they are unlikely to be fast on a bike!

I once took a younger bodybuilder colleague out for an evening ride over the local hills. He was strong enough to break his chain (mashing a 52/13 gear round on a climb! ), but trying to keep up with me half-killed him. (And I am not fast!)

I think this statement needs some clarification Colin. What is 'power' and how is it obtained? Can you demonstrate that strength
plays NO part in cycling fast? Can you have a lot of power but no, or minimum strength?

 

[ColinJ]

I think this statement needs some clarification Colin. What is 'power' and how is it obtained? Can you demonstrate that strength
plays NO part in cycling fast? Can you have a lot of power but no, or minimum strength?

That was covered by nickyboy in post #18.

The forces in your legs when walking up stairs are generally higher than those riders put through the cranks on a bike. Nearly everybody can walk up a flight of stairs, therefore nearly everybody is already strong enough to ride fast. The problem is that most people can't climb (say) 1,000 flights of stairs one after another - they can't sustain the power required. They could probably cycle at 30+ mph, but only for 100 yards or so.

Power is the rate of expenditure of energy. Energy (or work done) can be represented as a force times the distance for which it is applied. So, you could, for example, apply a lot of force over a short distance for one second, or (say) half the force for twice the distance for one second and the power generated would be the same. That would be like churning a big gear vs spinning half the gear twice as fast.

If you took that to ridiculous extremes, then you could apply a huge force and use a tiny cadence and still generate a lot of power but human bodies do not work efficiently like that. Similarly, you could apply a tiny force and use a huge cadence, but that isn't efficient either. Useful cadences lie somewhere between those extremes, and vary from person to person, and from time to time.

You certainly need to be pretty strong to be a track sprinter but most cyclists are limited by how much oxygen they can get round their bodies in their blood rather than how hard they can push on their pedals. That's why EPO is such a big deal - it doesn't make riders strong, it makes them powerful by artificially boosting that oxygen capacity!

Chris Boardman and Graeme Obree were 2 of the fastest cyclists ever but they weren't exactly massively strong.

 

[outlash]

Spot on Colin & Nicky. Can you now please explain this to my brother in law who complains his knees are knackered after a ride because he thrashes up the local climbs in the lowest cadence possible because in his words he's 'down on power'.

 

[ColinJ]

Spot on Colin & Nicky. Can you now please explain this to my brother in law who complains his knees are knackered after a ride because he thrashes up the local climbs in the lowest cadence possible because in his words he's 'down on power'.

I tried explaining to the body-building gear-masher that it would be better to spin a lower gear because if he carried on like that he would destroy the bike or his knees. He said that it felt weird to him to spin because he was used to 'pumping iron'. And 5 seconds later, his chain exploded under the strain!

 

[outlash]

Bless 'em! You can lead a horse to water......

 

[fossyant]

I havent an answer. Did a little off road a few years back with me, my 10 year younger runner of a brother, and my lad who was about 8.

Nothing technical. My lad battered him downhill and uphill. My brother can do a good 10k run, 30 something minutes.

Downhill was laughable, but that's a bike skill thing.

I also took him to the velodrome, and he crapped his pants at even doing the bottom of the track.

Dunno. I've been a road rider since I was young and went out with clubs from 16. I commute in traffic without too much worry.

There is lots for a fit runner to take in though.

To balance things out,

On a club run we went MTB'ing and got overtook by a fell runner !! Sometimes it is quicker walking.

 

[fossyant]

PS you try running for 30-60 minutes. I reccon you won't be walking the next day.

It's a different exercise. Cycling is non impact so allows different muscle use, running is impact, so some of the training is the shock resistance.

As a cyclist, you could keep up with a runner for a bit, but you'll be in serious pain next day, or indeed off to the physio.

Cycling is very specialised muscle wise. It translates to low impact endurance, but not to running

 

[ColinJ]

PS you try running for 30-60 minutes. I reccon you won't be walking the next day.

It's a different exercise. Cycling is non impact so allows different muscle use, running is impact, so some of the training is the shock resistance.

As a cyclist, you could keep up with a runner for a bit, but you'll be in serious pain next day, or indeed off to the physio.

Cycling is very specialised muscle wise. It translates to low impact endurance, but not to running

True!

For a while I ran to work and a friend cycled there. I borrowed his bike and found it hard going. He tried running after me and it half-killed him!

 

[fossyant]

I think us Cyclists are just weirdo's. Pain pain, go fast !!!! Repeat !

You'd make a movie out of that strap line !

Live, die, repeat.....

 

[T.M.H.N.E.T]

That was covered by nickyboy in post #18.

The forces in your legs when walking up stairs are generally higher than those riders put through the cranks on a bike. Nearly everybody can walk up a flight of stairs, therefore nearly everybody is already strong enough to ride fast. The problem is that most people can't climb (say) 1,000 flights of stairs one after another - they can't sustain the power required. They could probably cycle at 30+ mph, but only for 100 yards or so.

Power is the rate of expenditure of energy. Energy (or work done) can be represented as a force times the distance for which it is applied. So, you could, for example, apply a lot of force over a short distance for one second, or (say) half the force for twice the distance for one second and the power generated would be the same. That would be like churning a big gear vs spinning half the gear twice as fast.

If you took that to ridiculous extremes, then you could apply a huge force and use a tiny cadence and still generate a lot of power but human bodies do not work efficiently like that. Similarly, you could apply a tiny force and use a huge cadence, but that isn't efficient either. Useful cadences lie somewhere between those extremes, and vary from person to person, and from time to time.

You certainly need to be pretty strong to be a track sprinter but most cyclists are limited by how much oxygen they can get round their bodies in their blood rather than how hard they can push on their pedals. That's why EPO is such a big deal - it doesn't make riders strong, it makes them powerful by artificially boosting that oxygen capacity!

Chris Boardman and Graeme Obree were 2 of the fastest cyclists ever but they weren't exactly massively strong.

Such a beautiful post,I almost teared up with joy

 

[ianrauk]

I'm a cyclist and I can't run, let alone run quickly