Don't make excuses, make improvements

The summer bike’s tucked up in hibernation. The winter hack’s been dragged out and the rattling mudguards have been fixed.

It’s dark early – and it’s going to get cold soon. Welcome to winter riding.

It has its moments but mainly winter riding is sloooow. Why is that? We decide to look at a few of the common moans and summon the science.

>>> Keep riding with our top winter training tips

Moan: I’m slower because I’m on a heavy bike. It’s made of steel. It must be well over 10kg. Of course it’ll slow me down.

Truth: Not as much as you think, unless you only ever ride up steep hills. The British Medical Journal published a brilliant real world experiment by a consultant anaesthetist, who rode a total of 800 miles on two bikes during a regular 27 mile commute.

One was heavy (13.5 kg) and one light-ish (9.5 kg). Over almost 60 journeys, each around an hour and three quarters, divided half and half between bikes, his lighter bike was quicker – by a whole 32 seconds. His fastest single ride was . . . wait for it . . . on his heavy bike.


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Moan: Cold muscles don’t work as well. That’s why we warm up before a race. Ergo, I’m slower in winter. Because it’s cold.

Truth: We’ll give you that one. A one per cent decline in muscle temperature may, according to physiologist Len Bownlie, result in a reduction of muscle force generation of up to ten per cent.

So if your legs are cold, 18mph is going to feel as hard as 20 mph. But, hey, they’ll soon warm up unless you’re riding in the Arctic, and think of the training benefit.

(Photo: Andrew McCandlish)

Do cold muscles slow you down? Photo: Andrew McCandlish

Moan: Cold air is like syrup. It’s harder to get through it, meaning it’s slower.

Truth: To an extent, that’s true. Cold air has more molecules – in other words, it’s denser. However, it’s got to be very cold to make a big difference.

Assuming the same air pressure, there’s a 10% difference between air density at 25C and minus 5C meaning drag is increased by 10%. Over a 40km TT, you’d be 1:23 slower at minus 5C than 25C for the same effort. But how often is it -5C in the UK?


Watch our guide to winter cycling clothing


Moan: The “boil-in-the-bag” effect of all that winter clothing slows me down.

Truth: Hard to be absolutely definitive on this one. Over-heating is a limiting factor on performance, but no-one said going up a climb in the Alps in August was a refreshingly cool experience.

However in summer, exposed skin helps the body’s natural cooling mechanism – sweating – to regulate temperature. That’s not as efficient a system in winter when little skin is exposed. But it’s probably more psychological than physiological.

Optimal performance requires careful nutrition

“How long until the cafe? I need a pee”

Moan: I keep having to stop for a pee – I’m sure it’s because it’s cold.

Truth: We can see how that would play havoc with PBs. And it’s rock solid science. The cold does affect physiology and it changes the way the body processes liquid.


Read more about winter cycling


Basically, more water gets into the bloodstream and the kidneys respond by filling the bladder – which needs emptying more often. Even though it feels all wrong to be drinking a cold drink when it’s cold, you actually should.

Michelin Pro4 Endurance 28mm tyres by Jack Elton-Walters 2

Warm your tyres up by riding further…

Moan: My tyres definitely don’t roll as fast when it’s cold.

Truth: There’s something in this. Tyres roll faster when they’re more elastic and bounce back into shape quicker. They do this less when it’s cold.

It’s estimated that for every 6C drop in temperature the rolling resistance of a tyre will increase by (a coincidental) 6%. Converting this to lost speed is tricky, given the huge variation in tyre types and pressures. But do tyres roll slower in the cold?

Yes, they do.

>>> Click here for our winter tyres buyer’s guide


So, not all the moans are justified. But some are, and even though they may not make much difference individually, their cumulative effect is to slow us down.

And there’s another thing – we just don’t feel fast in winter. Bulky clothing, heavy bikes and rubbish roads all take their toll on our riding psyche.

And that’s probably the biggest single reason we’re slow in winter.

  • trummy

    This was an account of the explanation that I read re the consultants experiment. I accept that I have never cycled between the two. If however the timing was taken in the Sheffield to Chesterfield direction then I presume it would be a descent overall, (which would benefit the heavier bike.)

  • Karl Thornley

    You’ve never ridden between Chesterfield and Sheffield if you think there’s not much up and down!

  • Rouleur99

    quite right. it will be changed.

  • Evan Stitt

    Good point. Also, if his commute is flat, it really makes no difference. If he’s commuting up Alpe d’Huez, however, that’s another story.

    Although, if his commute is Alpe d’Huez, he’s really got nothing to complain about anyways.

  • trummy

    My understanding that this was to simulate the difference between the summer and winter bike. My thoughts are that the winter bike would have heavier wheels and chainset, what difference would that make? (gyroscopic effect ) Also loading the rider is different than loading the bike (sprung/unsprung weight) so I consider their experiment is fundamentally flawed. As for the reference of the consultant anaesthetist experiment, that was very interesting,as I recall the commute was between Sheffield and Chesterfield, without much up and down or change of pace, so once he was up to speed the small weight difference did not seem to be much of a problem.

  • blemcooper

    “It’s estimated that for every 6C drop in temperature the rolling resistance of a tyre will drop by (a coincidental) 6%.”

    I think you meant “will increase by (a coincidental)…”

  • Rouleur99

    I think he was being chased or was chasing a colleague at the time – so a further complicating factor Jon – additional motivation. Bit of fun rather than a scientifically designed experiment I think.

  • Jon

    “His fastest single ride was . . . wait for it . . . on his heavy bike.”
    If he was the subject, the results are tainted by experimenter bias. In other words, he knew what hypothesis the study was setting out test, had an interest in the outcome, and could have deliberately or subconsciously pushed harder on the heavier bike.