[tomtom]

Its all here folks...
http://www.bbc.co.uk/news/health-11958903

Dig out yer penny farthing...

[Sloper]

Give it a few years and the fad will change, probably back to golf.

[tlr]

Yeah, but they are nice.

There is a similar thing on the Zipp wheel website where there are some 'facts' about the time saved by shedding a few pounds off the bike - negligible. Obviously they claim that switching to aero wheels however will save time.

Anyway, it's all just an excuse to buy carbon shiny things...

[slackline]

Not a great sample size to be making such generalisations really!

There is however the fact that if having spent some money on something it means that people (in general and not just this one person who was already a keen cyclist) to use it then that will have benefits for those individuals.

Also, why, just because someone's "dream bike" doesn't actually save them any time does it mean that they will be disappointed at having got it at a slightly cheaper rate thanks to the Cycle to Work Scheme?  Maybe they just wanted that bike, regardless of whether it would save them any appreciable time, and they were happy to get it cheaper.

[fatkid2000]

I've got the BMJ sat in the kitchen so I'll have to look at the methodology, however I used to do the same commute as the author and the time difference was huge mainly depending on traffic etc. Anything up to 10-20 mins extra if the traffic was shit.

[slackline]

I've got the BMJ sat in the kitchen so I'll have to look at the methodology, however I used to do the same commute as the author and the time difference was huge mainly depending on traffic etc. Anything up to 10-20 mins extra if the traffic was shit.

That'd probably be why he timed the journey over six months, deciding which bike to take on a given day with a coin toss (so roughly 50/50 never perfect but not too far off, thats chance for you) and then compared the mean journey time between the two (although there is no mention of the standard deviation/variance in the BBC write-up though which is what you're getting at).

Besides, who reads print these days, its on-line (& open source) (although obviously taking a mag to the toilet to read is easier and quicker than breaking out the iFern).  Not that it mentions the sd/variance of journeys made on each bike either, nor is there a mention of how the p-value was calculated (but most likely to be a simple t-test).

Nice that he gives a Confidence Interval for the estimate of difference between the two means.

[tomtom]

The weight difference between carbon and steel bikes were less than I thought (9.5 and 13.5kg - OK theres rotating weight as well) but lets say he weighs 70kg..

Him + Carbon Bike 79.5kg
Him + Steel Bike 83.5

as a % difference thats not much... (5%)... I thought (when I read the BBC article) that he was riding in on a 20kg+ monster... the weight difference is probably within the order of which the riders body weight varies over the year.. (certainly the same as a laptop and 2-3 books..)

[fatdoc]

** cough **

very proud moment....

( I have the pleasure of working with him)


and, he is very fit... so will make a bigger difference if you are a bit chubby [like me]

fatkid.. the large sample size satisfied the BMJ proof readers. The stats hold up.

[Norton Sharley]

tomtom:  the rotating mass difference needs to be cubed and the sprung mass squared to consider the true effect.  In other words forget a carbon frame and get carbon wheels and bouncy bits.

My tube has a mass of 100g, my tyre 1000g and my tool 125g. How far off the norm is that statistically?

[psychomansam]

** cough **

very proud moment....

( I have the pleasure of working with him)


and, he is very fit... so will make a bigger difference if you are a bit chubby [like me]

fatkid.. the large sample size satisfied the BMJ proof readers. The stats hold up.

Surely your extra (beer) weight just means the bicycle weight difference will be even less significant as it will be less sizable as a % of total weight difference.

The *cough* study, doesn't mention fitness having any relevance, i'm sure it would've...

Seriously though, i'd expect the opposite to be true. 5% weight difference to joe bloggs means sweet F.a, while as to someone who's trained and plateaued, it'll be quite sweet.

I do agree with the *cough* study that we waste a lot of money on over-technical gear we don't need.

long live UKB freecycle...

[fatdoc]

context needed..

 the Xmas BMJ only has * cough* medical studies in it... it's tradition.

to get a paper accepted in it is however probably harder than any other week of the year!

think medically amusing private eye type humour.. not "new drug heals all" revelations

Hence the overtly proud post above.

[tomtom]

There's alot of coughing going on amongst you medics

[fatdoc]

H1N1 is back....
 

I think I need a vaccine

[tlr]

I think all this proves is that Dr Groves needs a lighter carbon bike...

Just read the article, and I have to say that it is an impressive amount of miles that he has covered in 6 months. Very good effort.

[fatkid2000]

 

Just don't tell the Daily Mail.
It's in the seasonal vaccine anyway.

Proud moment for Chestefield anaesthetic dept ?

[mr__j5]

I would suggest that the route is neither hilly enough or long enough to really notice a difference.

If he road 100miles with 2000m climbing in it then he should see a noticable difference in expended effort, if not time.