How to run 50% faster without external energy (2020) • Hacker News Board

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

#181

Post by pixl97 » Tue, Oct 24, 2023, 1:49 PM UTC

Lio wrote: post #156

Retric wrote: post #119

Earlier quoted context omitted.

People do ski faster than that but low friction means slower deceleration which is a huge reason it’s even possible to learn reasonably safely. This applies to basically all high speed winter sports and is under appreciated by most viewers. Similarly landing from a jump or fall on a hill the force vectors mean people are mostly sliding on the surface resulting in significantly less forceful impacts. Biking at 45-48 M…

> Biking at 45-48 MPH is rare, dangerous, Not sure where you get that from. Amateur road cyclists can pretty easily reach 50MPH given a long enough hill and do so pretty uneventfully. That's dressed in just shorts, jersey, helmet and fingerless gloves. A professional racing cyclist could easily break 60MPH on closed roads and even 80MPH on occasion. For someone like Tom Pidcock who knows[1]. In the linked video he's…

The amount of time that standard cars reach 100MPH is rare, and it is dangerous. Professional racing drivers have cars that reach 200MPH+, it is insanely dangerous and all kinds of specialized equipment is in place to keep the driver from dying.

You seem to be conflating that if someone reaches a particular speed it is safe which the whole 'velocity squared' doesn't give two damns about. The energy you have to safely dissipate increases very quickly.

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

#182

Post by xctr94 » Tue, Oct 24, 2023, 1:57 PM UTC

scns wrote: post #157

xctr94 wrote: post #153

Earlier quoted context omitted.

My god, yes. I had knee and ankle pain while running, then also while walking. Too much padding was allowing me to walk incorrectly. After being ‘prescribed’ flat, flexible, low-stack shoes, all the pain went away. My toes are more spread out and my abductors are thicker. Nice gains! (Still, your mileage may vary, I included lots of exercise specifically for the transition. And still run in Altras.)

In Born To Run they cite a study that surprised it's own authors. The more expensive the running shoe, the higher the rate of injuries i.e. the better the damping the weaker the foot and legs. And another one that showed the impact on the leg is 7 times higher in running shoes than barefoot. On mobile may provide links later. [edit] Unable to find the one i searched but found this article claiming a 2-3x times bodywe…

I know! This and ‘Exercised’ are what got me running. Both excellent, evidence-based books. I run in Altras for the transition, but hope to eventually have the legs for running in something that qualifies for barefoot (rise/stack/flex).

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

#183

Post by wolverine876 » Tue, Oct 24, 2023, 2:43 PM UTC

Someone wrote: post #159

wolverine876 wrote: post #121

Earlier quoted context omitted.

My understanding is that a species' maximimum speed depends simply on muscle mass. The reason elephants don't outrun cheetahs is that they accelerate more slowly and run out of energy before hitting the top speed their muscles could produce. Look up allometry for more. There are formulas for calculating top speed based on mass.

> My understanding is that a species' maximum speed depends simply on muscle mass If so, that doesn’t mean that they would get faster if only they got more muscle. I would expect that species evolve towards not having more muscle than they can effectively use. I think looking at elite human runners supports that. At longer distances, they get less muscular. > The reason elephants don't outrun cheetahs is that they [……

>> The reason elephants don't outrun cheetahs is that they accelerate more slowly and run out of energy before hitting the top speed their muscles could produce.

> Big beasts, in other words, run out of so-called anaerobic energy, supplied by the muscles, before being able to reach their theoretically maximum speed.“

Aren't we saying the same thing?

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

#184

Post by DropPanda » Tue, Oct 24, 2023, 4:31 PM UTC

chongli wrote: post #98

DropPanda wrote: post #22

Earlier quoted context omitted.

The proposed device is predicted to allow almost double that speed. I think it’s pretty cool.

What? That’s faster than track cycling world records! The 200m flying start record is 9.1s which translates to 79km/h. The makers of this device are proposing to let humans run faster than a world record track cyclist!

Maybe I got the unit conversions wrong. The theoretical maximum speed is shown to be on par with world record track cyclists.

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

#185

Post by hinkley » Tue, Oct 24, 2023, 5:11 PM UTC

pharmakom wrote: post #68

hinkley wrote: post #37

Earlier quoted context omitted.

One of the reason pro cyclists clip their feet to their pedals is so they can load the “other” leg through the back of the stroke, and across the bottom as well by pulling back on the loaded leg. Come unclipped in a sprint and you’re fucked. Sounds like this is the same thing for running.

I believe this was disproven actually. The real reason is security under heavy power output.

I’m looking at these experiments and I am dubious.

How do you explain the effect in OP’s device if this is “disproven”? Nobody seems to have offered an alternative theory.

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

#186

Post by hinkley » Tue, Oct 24, 2023, 5:14 PM UTC

karmakurtisaani wrote: post #162

john61 wrote: post #151

My father built a prototype of such a device 20 years ago. He abandoned the project after trying the prototype, because it accelerated dramatically and he could not brake. He jumped sideways into the gutter and was really scared. My personal opinion is that the bicycle is already invented and its excellent energy efficiency is hard to beat.

Those springs look like a great way to get rid of any unnecessary teeth. Can't achieve that with a bicycle.

I know some people who tried.

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

#187

Post by hinkley » Tue, Oct 24, 2023, 5:21 PM UTC

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...

The tread only lasts for 200 miles? That’s something like a new pair a month while training isn’t it?

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

#188

Post by hinkley » Tue, Oct 24, 2023, 5:24 PM UTC

ntonozzi wrote: post #110

pixl97 wrote: post #96

Earlier quoted context omitted.

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.

With bikes at least the mechanics of the bicycle mostly work for you instead of against you. Riding no handed wouldn’t be something children learn on their own if the system weren’t at least slightly self-righting.

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

#189

Post by hinkley » Tue, Oct 24, 2023, 5:32 PM UTC

DropPanda wrote: post #22

ck2 wrote: post #4

Inline skates on flat ground are technically "no external energy". And they can race a marathon in under an hour, so that's 26+ mph (42 kph)

The proposed device is predicted to allow almost double that speed. I think it’s pretty cool.

An odd sense of calm would come over me any time I got my bicycle going over 40 mph. “If I fall now, I’ll bounce twice and then blackness.” I no longer recall my top speed, either 42 or 45. One particular little river valley with very good pavement and clear sight lines.

There is no amount of money you could pay me to run at 52 mph.

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

#190

Post by hinkley » Tue, Oct 24, 2023, 5:36 PM UTC

303uru wrote: post #66

fwip wrote: post #12

Earlier quoted context omitted.

Presumably there are areas/applications where "running" is important - otherwise we can just use a bicycle.

Historically, human survival. No other animal can cover ground the way we can. We've evolved to be highly efficient, one example; we cool ourselves better than any other animal we can maintain a fairly high power output almost indefinitely due to sweating.

There was a comedian who hit upon this in his act. Not only are we top tier endurance predators, we also have a very high wound closure capability. To the herbivores on earth we are all Mike Myers. Stop for a minute and he’s right there again. Wound him, and he comes right back.

He riffed on why aliens are always the scary ones in movies. Maybe we are the scary ones.