Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

How to run 50% faster without external energy (2020)

science.org

Post reply on HN
Print view View original

101–110 of 206 posts

Re: How to run 50% faster without external energy (2020)

#101

Post by discreteevent »

ip26 wrote: post #71
justsocrateasin wrote: post #61

Earlier quoted context omitted.

This is true for certain metabolic zones but not others. If you're sprinting then yes, you get a higher power output while pulling up on the pedal. However if you're going for any kind of endurance (longer than a minute) the limiting factor is not muscular but cardiovascular/aerobic, and using less efficient muscles (the ones used for pulling up) will actually hinder your performance since you'll need to be supplying…

Your goal in endurance conditions is to maximize the aerobic pathway, which means maximizing the number of active mitochondria. Recruiting more total mitochondria from more total muscle fiber will give you greater aerobic power output.

Like the parent said, the goal is efficiency not maximum power. And as another comment said, in practice the pros do not pull up. If there were even a minute gain in doing so, they would train themselves to do it (in fact some of them used to in the past before they figured out that it was a waste of time)

Re: How to run 50% faster without external energy (2020)

#102

Post by MrRolleyes »

tiffanyh wrote: post #20

Nike Vaporfly. I'm surprised it wasn't mentioned that 2 recording breaking marathon runs were by athletes wearing the Nike Vaporfly shoe. The shoe was ultimately banned due to the giving too much "bounce" (free energy) to the runners. https://www.reuters.com/article/us-athletics-shoe/nike-proto...

[dead]

Re: How to run 50% faster without external energy (2020)

#103

Post by chrisweekly »

asoneth wrote: post #64

Their model seems to predict a theoretical top speed of 18-20.9m/s (or 40.0-46.8mph, 64.8-75.2kph): https://www.science.org/doi/10.1126/sciadv.aay1950#F2 As much as I want to imagine people chasing down cheetahs, without empirical testing I have to admit I am skeptical of their claims.

still slower than cheetahs

Re: How to run 50% faster without external energy (2020)

#104

Post by MrRolleyes »

pixl97 wrote: post #96
asoneth wrote: post #64

Their model seems to predict a theoretical top speed of 18-20.9m/s (or 40.0-46.8mph, 64.8-75.2kph): https://www.science.org/doi/10.1126/sciadv.aay1950#F2 As much as I want to imagine people chasing down cheetahs, without empirical testing I have to admit I am skeptical of their claims.

Eh, I'm not worried about their top speed claims... I'd be far more concerned that you could reach those speeds, and the hospital bills incurred by the inevitable accidents. You're going to have to have a massive amount of safety gear weighing you down (thereby losing speed) to keep you from busting your head open like a rotten cantaloupe moving that fast. Velocity squared is a bastard.

[dead]

Re: How to run 50% faster without external energy (2020)

#105

Post by stouset »

hinkley wrote: post #85
stouset wrote: post #63

Earlier quoted context omitted.

> The idea that your muscles have enough strength on the upstroke to contribute meaningfully to cycling is actually a bit of a misunderstanding. Absolutely not, and there are plenty of easy counterexamples. If you've ever raced track, team pursuits start from a dead standstill. You have to expend a ton of force to turn a huge gear, and the contribution of the lifting leg is crucial to getting up to speed. Of course i…

> but all four of your limbs are at maximum exertion getting the bike up to speed. Oh goodness yes. When you’re going full out it’s like you’re trying to wring water out of a steel towel. Pull up on left handlebar while using right arm to prevent oversteer. Another fun failure mode is when you don’t quite trust your handlebars. I’m either not going to pull on these or I’m gonna stop before the Big Hill to find an All…

> trying to wring water out of a steel towel

I’m stealing this! Spot on.

Re: How to run 50% faster without external energy (2020)

#106

Post by stouset »

jeffbee wrote: post #80
stouset wrote: post #63

Earlier quoted context omitted.

> The idea that your muscles have enough strength on the upstroke to contribute meaningfully to cycling is actually a bit of a misunderstanding. Absolutely not, and there are plenty of easy counterexamples. If you've ever raced track, team pursuits start from a dead standstill. You have to expend a ton of force to turn a huge gear, and the contribution of the lifting leg is crucial to getting up to speed. Of course i…

We have a large amount of power meter data demonstrating that elite and pro cyclists do not, in fact, exert much force on the rising stroke when in the saddle. They maintain a net downward force on the pedal most of the time. The benefit of clipless pedals is repeatable positioning and the ability to start the downstroke right at top dead center, without slipping off the pedal. The benefit is not from powering the ba…

Yet cycling events are frequently won out of the saddle on the slopes or out of the saddle in the sprint.

And yes, sometimes they’re won by someone time trialing away from the pack while in the saddle. But even then, most of the time it’s a breakaway pack which fights for the podium in an all-out sprint.

Re: How to run 50% faster without external energy (2020)

#107

Post by stouset »

rhn_mk1 wrote: post #69
stouset wrote: post #63

Earlier quoted context omitted.

> The idea that your muscles have enough strength on the upstroke to contribute meaningfully to cycling is actually a bit of a misunderstanding. Absolutely not, and there are plenty of easy counterexamples. If you've ever raced track, team pursuits start from a dead standstill. You have to expend a ton of force to turn a huge gear, and the contribution of the lifting leg is crucial to getting up to speed. Of course i…

Those are not necessarily examples of lifting . Those could as well be explained by the contribution of not pressing on the opposite pedal (to keep the foot from sliding). And not pressing doesn't shine any light on the force of lifting.

> Those are not necessarily examples of lifting.

They are, and this is trivially demonstrable by literally just trying it on a bike. Seriously. Go put a road bike in the highest gear and try to get up to speed from a standstill. Not only will you be pulling up on the rear pedal, but you’ll be using your arms to try and wrench the handlebars off the stem too.

Go climb a steep hill. Same thing occurs. It’s not like this is subtle. The contribution of your rear leg very clearly contracting will be impossible to miss.

Re: How to run 50% faster without external energy (2020)

#108

Post by jph »

bee_rider wrote: post #81
jackmott42 wrote: post #73

Earlier quoted context omitted.

No it did not.

It is hard to say if it is implausible without the time unit. 2km/day? I believe it. 2km/s? Seems unlikely.

Ha! Yes you're right, units matter. For me it was 2 km/hour, on rides for an hour or so typically above 20 km/hour, on a hybrid bike, on long streets in Marin. The ellipticals worked especially well, for me, in combination with bar ends.

Re: How to run 50% faster without external energy (2020)

#109

Post by moron4hire »

mikestew wrote: post #36
tiffanyh wrote: post #20

Nike Vaporfly. I'm surprised it wasn't mentioned that 2 recording breaking marathon runs were by athletes wearing the Nike Vaporfly shoe. The shoe was ultimately banned due to the giving too much "bounce" (free energy) to the runners. https://www.reuters.com/article/us-athletics-shoe/nike-proto...

Mmmm, not quite. The ones you and I can buy have a single plate, and stack height of 36mm. The ban was for shoes (like the VaporFly prototype) with >40mm stack height and/or multiple plates. Not that this article clears the matter a whole lot, but there is more information (sorry, couldn't find a succinct article on the topic): https://www.cbsnews.com/news/nike-vaporfly-running-sneaker-n... I've used them (as a ~3:00…

I wonder if that would do anything for my plantar fascitis...

I made a mistake in shoe choice for a vacation one year, before I knew how much my wife absolutely insists on walking at least 10 miles a day. That was 8 years ago and I still have pretty severe pain almost every morning.

Re: How to run 50% faster without external energy (2020)

#110

Post by ntonozzi »

pixl97 wrote: post #96
asoneth wrote: post #64

Their model seems to predict a theoretical top speed of 18-20.9m/s (or 40.0-46.8mph, 64.8-75.2kph): https://www.science.org/doi/10.1126/sciadv.aay1950#F2 As much as I want to imagine people chasing down cheetahs, without empirical testing I have to admit I am skeptical of their claims.

Eh, I'm not worried about their top speed claims... I'd be far more concerned that you could reach those speeds, and the hospital bills incurred by the inevitable accidents. You're going to have to have a massive amount of safety gear weighing you down (thereby losing speed) to keep you from busting your head open like a rotten cantaloupe moving that fast. Velocity squared is a bastard.

People bike and ski that fast every day with no protection other than a helmet.
Post reply on HN