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

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

#161

Post by scns »

dmos62 wrote: post #131
moron4hire wrote: post #109

Earlier quoted context omitted.

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.

Take this with a bag of salt, but I've heard people get notable improvements in joint, feet, leg health from switching to barefoot shoes. They also tend to be extremely comfortable. I've been using them exclusively ~5 years and ran a half-marathon in them. For what it's worth, a physical therapist told me my feet are remarkably muscular. I like the UK manufacturer Freet, btw.

> I like the UK manufacturer Freet, btw.

Thanks for the recommendation, might give em a try. Tested some brands so far, stayed with Vivobarefoot.

[edit] Disclaimer: Repeat customer

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

#162

Post by karmakurtisaani »

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.

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

#164

Post by hermitcrab »

rottencupcakes wrote: post #48
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.

The idea that your muscles have enough strength on the upstroke to contribute meaningfully to cycling is actually a bit of a misunderstanding. Your leg muscles for lifting are much much much weaker than your leg muscles for pushing - they're designed to only lift up the weight of your leg and not much more. The main advantage of the clips is to keep your leg in contact with the pedal throughout the cycle and make sur…

>Your leg muscles for lifting are much much much weaker than your leg muscles for pushing

And yet Thai boxers appear to be able to generate at least as much force using upward knee strikes as push kicks.

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

#167

Post by Retric »

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…

Rare as in what percentage of the time is someone on a bike going 45+ MPH?

I’d be surprised if it’s more than 1% for more than a handful of people. An ultra elite athlete on a normal bike can hit that on level ground in an absolute sprint, but you can’t sprint for very long. Going downhill requires time spent going up the hill.

The women’s 1 hour speed record is 30.6MPH, the men’s is 35.3 MPH. So sure downhill, rolling start, or motor-paced people can reach extreme speeds but they really aren’t doing so for hours a day. Streamlined recumbent bicycle can do it far more easily but that’s niche territory.

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

#168

Post by culebron21 »

helsinkiandrew wrote: post #8

Haven’t similar devices been around for ages https://en.m.wikipedia.org/wiki/Jumping_stilts

I've used them for a year, and fell from them twice, the second time because a rubber shoe of the stilt broke apart, and strained a lot my knee. No broken bones, but it took a week to start cycling, then in 2 weeks I could walk almost normally, and it took whole 3 months to stop feeling the pain. I sold them after that.

Running in them is VERY hard, even if you do it properly (landing on straight legs, to not dampen the energy). You can run only at high power mode, like sprint, for 200-300 metres.

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

#169

Post by culebron21 »

tech_ken wrote: post #19
helsinkiandrew wrote: post #8

Haven’t similar devices been around for ages https://en.m.wikipedia.org/wiki/Jumping_stilts

No, the difference is when/how you load the springs. This proposal seems to be that you load the spring with your leg in the air before it makes contact with the ground (achieved by attaching the top of the spring up the leg), then land the loaded spring and unload. Their argument is that this allows for higher overall energy output from the human body (akin to cycling). In a jumping stilt you're loading the spring w…

You do the same in jumping stilts. You move arms and body in the air to increase jump amplitude, and land on a straight leg to compress the stilt and let it bounce back.

If you try working with hips/knees while touching the ground, you'll amortize all the energy you generated, and exhaust quickly. Beginners suffer from this, and it takes some learning to run properly.

Also, the energy converts from motion into spring load and back into motion, and you can keep adding it. Pro stilt jumpers can jump several times with more and more energy and increase height.

When I took such classes of spring stilts, the coach showed us jumping above 2.5 m. Me and a classmate held a ribbon in our hands above our heads (we stood in stilts too), and he jumped several times towards us, each time higher, and finally flew above the ribbon. This is actually much more work than olympic jumping, where the COG of the jumper is actually a bit lower than the bar. This guy had to jump with COG much higher than the ribbon.

But as I mention in the other post, if you fall down even routinely while running on stilts, it's very painful -- falling forward with your arms extended ahead, you still hit the ground with the ribs. Then they ache a month.

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

#170

Post by Retric »

lloeki wrote: post #158
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, and free of tripping hazards which I think are a much larger concern Two decades ago I was doing downhill MTB. On a road section it was quite frequent for me to reach those speeds†; and that's with a MTB (tuned to that end), friends†† with road bikes reached these speeds with ease, some of them regularly hit 80-90kph on specific sections. One of the wide hairpin turns happene…

‘On specific sections’ doesn’t mean people are spending a lot of time doing something. If you’re going downhill at 45+ MPH you quickly run out of hill.

I doubt the total time by any bike rider over 45 MPH was 0.1% of the total time people ride bikes.

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