Fitter doing running, rather than cycling ?

[MacB]

OK then, that makes sense. Thanks for the info...and I'll remember to search for other threads before posting.

I would agree that the OP shouldn't be surprised that his fitness levels are dropping.

Kirstie, just to muddy the waters further, when equating running to cycling the effort level matters. A factor of 4-5 seems about right to me but only if you're putting in enough effort on the bike. Running, especially if unfit, requires a base level effort considerably higher than that required for moving a bike. If you only pootle on the bike then a factor of 10-15 might be more accurate.

 

[Kirstie]

Kirstie, just to muddy the waters further, when equating running to cycling the effort level matters. A factor of 4-5 seems about right to me but only if you're putting in enough effort on the bike. Running, especially if unfit, requires a base level effort considerably higher than that required for moving a bike. If you only pootle on the bike then a factor of 10-15 might be more accurate.

Well I'm certainly not a pootler...

 

[Davidc]

MacB has to be right about the base effort level. The OP appears to have had a reasonable fitness level in the recent past, so I would have thought he'd have needed very much higher performance and duration than he says he's been doing in order to maintain that, let alone improve it.

 

[MacB]

Well I'm certainly not a pootler...

sorry, wasn't suggesting you were that bit was more a general response re the OP. The posted average speed was very low for someone who has recently led an active life. It was even lower than my average when I started cycling and that was from true couch potato land. Going at that pace would probably be outdone by running by a factor of 15 to 1. Maybe there should be some sort of scale that equates the two, purely on effort level alone, distance would be another factor. But effort could be expressed in a form like:-

5mph bike = slow shuffling walk
8mph bike = reasonable paced walk
10mph bike = fast walk or gentle jog
12mph bike = jogging
15mph bike = medium run
18mph bike = running
20-25mph bike = serious running
25mph+ bike = athlete and not to be confused with the likes of me

obviously this has been calculated using the most stringent of scientific methods

 

[Perfect Virgo]

Kirstie, just to muddy the waters further, when equating running to cycling the effort level matters. A factor of 4-5 seems about right to me but only if you're putting in enough effort on the bike. Running, especially if unfit, requires a base level effort considerably higher than that required for moving a bike. If you only pootle on the bike then a factor of 10-15 might be more accurate.

Yes this is a much closer comparison MacB and your proviso is right too, I believe. I know how I feel after a 15 mile run and it's similar to a 75 mile ride. Whenever I read these cycling/running posts I am always tempted to repeat that a good runner can turn to cycling and get going at a fair pace but a cyclist might take time to build the strength and stamina needed for running. As others have mentioned, this is because there is no respite in running and each stride launches both feet off the ground.

The OP's approximately 10k bike ride in 50 minutes can't be right surely. Most fair runners would expect to run 10k in that time. I can do it in 55 minutes but I'm 52!

 

[jimboalee]

Kirstie - there's been a few threads on this before.

I think the judgement varies on whether you're a cyclist who runs a bit or the other way round. Personally I'd consider a marathon run (26.2 miles) to be worth about 125 miles, so call it 5:1 ratio. A huge difference is made by the pace, intensity and frequency e.g. I can cycle 75 miles a day for many days in a row but I couldn't run 15 miles a day for too long! The impact and damage of running is much greater.

I'm running a 10 mile race on Sunday, probably in about 75 minutes, which will hurt a lot more than a steady 70-80 mile ride, but might be comparable to a hard 50 mile TT perhaps.

Just observations really.

Which means a bicycle is 2.5 times as fast as a runner for half the energy per time.

 

[Davidc]

obviously this has been calculated using the most stringent of scientific methods

It'll never get past peer review.

25 mph is impossible (unless going down a steep hill). It used to be possible on bikes made 30, or even 20 years ago, but there's something about new ones that stops them averaging over about 15 mph.

I used to be able to average 20 mph over 50 miles on bikes from the 60s, 70s, 80s. I can only just about manage 50 miles, and that at between 10 and 15 mph average, on bikes from the past 5 years!

It has to be the bikes, after all it's the same rider, so I've controlled for that, and some of the routes are the same.

 

[jimboalee]

A definitive explanation.

To quantify the efficiency COMPARISON of running vs cycling, it is necessary to measure the effort of the athlete.

This can be done by analysing the CO2 and O2 going into and out of the patient's lungs.

Then when the poor sapper is extracting the same O2 from the inhaled air, take a note of his speed of forward motion.

UC Santa Cruz did this with gas analysers on the back of a truck following runners and cyclists, and a flexible hose apparatus to the victim.

Ref. Albert C. Gross, Chester R. Kyle and Douglass J. Malewicki

 

[jimboalee]

Read through this.

http://books.google.co.uk/books?id=...resnum=3&ved=0CBAQ6AEwAg#v=onepage&q=&f=false

 

[_Chris_]

Sorry for the delay in getting back on this, I haven't been receiving emails to say replies have been posted, but will look into that straight away.

Many thanks for the very informative replies, and yes, I may have got my calculations a little wrong - I took the calculations a couple of years ago, but didn't start the cycling until a short while back.

Will update by the weekend, when I have another chance to get out in the car.

 

[ASC1951]

Will update by the weekend, when I have another chance to get out in the car.

??

You don't mean you drive to where you start exercising? Rather defeats the point.

 

[_Chris_]

You don't mean you drive to where you start exercising? Rather defeats the point.

? ?

Not quite - I need to drive round the circuit first, to measure the distance !

 

[I am Spartacus]

Not such a strange behaviour.
When out cycling, I do get passed by many a car loaded with MTBs (usually) on the rack.
I also live in a less than salubrious part of the UK....running around is a pain..
dog shoot... pissed up teenagers... feckless unemployed ( oh feck .. that's me) ...MTBers riding on pavements ...arsey dogowners .. more arsey doggers... I can go on.. get the picture?

 

[alecstilleyedye]

? ?

Not quite - I need to drive round the circuit first, to measure the distance !

a bike computer will be more accurate. allow for 10% deviation with the car…

 

[fay144]

Hi Chris, I use the gmap-pedometer or mapmyrun websites to map out routes to find distance. It's a lot quicker than driving it. And it's handy to be able to plan runs/bike rides in advance.

I was thinking about this thread when I was running up a big hill on the way into work this morning. Maybe it's because I'm a runner who is new-ish to cycling, but I am certain that there is no way I was exherting 4 or 5 times the effort of cycling up the same hill. I wouldn't even have said it was double. Cycling up steep hills really takes it out of your legs... with running you can just plod away at it. On the flat, then I can see there is a difference... 5 times still seems a lot though, to me.