A caveat to “the bike doesn’t matter” is you have to have a bike with gearing to keep you fairly comfortably below threshold on the climbs for 24 hours
Not necessarily true.
You don’t ride until exactly 24hrs and then mark your position and come to a stop. You ride as many laps as you can. That might mean riding X laps in 23hrs and 10 minutes vs the same X laps in 23hrs and 59 minutes…and if you don’t have time to conceivable complete the next lap, theres no sense in starting it. On the other hand a lighter bike might get you so far that you are able to complete one more lap, in which cause you might end up riding longer despite riding a faster bike…so it goes both ways.
It not near, it makes no odds if you are talking about “effort”. What you’ve done above is talk about time which is different. If you are talking about pure effort then the bike makes no difference.
You can ride a range of bikes round a circuit and maintain the same effort I.e power output.
And to further muddy the waters, my understanding is that at the 24 I’m doing if you pass the post at 23:59:59 you get another lap with no time limit. So I can see some of the serious competitors either hammering the last-but-one lap to make the cut or soft-pedaling to conserve energy for a last lap.
Just to say at this point I’m hugely grateful to everyone who’s contributed to this thread. It’s been a very helpful and interesting read.
GLTGH: I’m being obtuse, I’m sure, but I don’t understand how you can isolate effort in terms of Watts from time. If you take more time to climb a hill at the same Watts (because you’re wearing a rucksack full of bricks or there’s a headwind) that’s a bigger effort, surely. Granted if you take a time-slice and look at instantaneous effort (supposing that to be possible) then Watts is Watts, so to speak. But you can’t: power is by definition a rate; it takes place over time and an application of power must have a duration.
Add in the bio-energetics and things get even further removed from the time-slice picture: compare energetics at 30 seconds with those at three minutes and three hours and you could be forgiven for thinking you were looking at different organisms rather than the same rider on the the same day.
But lets factor out time so I can try to address your point as best I can: take two riders on the same hill, same speed (so same time-to-complete and hence we can factor time out of the discussion) and identical lactate curves. Rider H has a heavier bike than rider L. They each take 15 mins to complete the hill but—-and here’s the thing—H is over threshold whereas L is below her threshold because of the marginal difference in weight. H gets to the tophaving blown his doors from spending too long above threshold; L went up at sweet spot which was very sustainable for her. Even on the time-slice picture their respective bio-energetics were different solely because of the weight difference.
Absolutely. In fact I’ll be running an MTB 2 x chainset at 24 40! Much to the amusement of everyone else I’m sure. I like to spin and the steepest hills at the 'ring hit 20% but 40 x 11 is plenty fast enough for 24 hour race with my FTP!
Thanks for clarifying, P13. I obviously wasn’t putting out many watts when I read that the first time. You’re both absolutely right to say that n Watts = n Watts
You likely are just are using the term different to me.
For me, the effort required uphill is about how much power you are generating to overcome gravity. It’s about the rate of energy use. Where as you are using effort to mean total energy expended to get from bottom to top.
Thus for me I can use the terms VO2 effort or Threshold effort or Sweetspot effort or tempo effort or endurance effort. Because I’m using effort as an equivalence of the intensity you’re working at. But you could not use those terms as you are referring to total energy expended which the above terms do not include.