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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)

#171

Post by Lio »

jdietrich wrote: post #120
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…

>the contribution of the lifting leg is crucial to getting up to speed This might feel true, but it isn't. Buy or borrow a dual-sensing power meter (Garmin Rally, SRM X-Power etc) and you can see for yourself - there's practically no useful power in the upstroke. Toe clips or clipless pedals can extend the power stroke, but only by a few degrees at the bottom of the stroke. https://bythlon-pedal.myshopify.com/pages/t…

Clipless pedals also keep your feet on the pedals at high cadences.

I'd guess the highest power and torque outputs in cycling are from track sprinters. If you look at what they use it's both cleated pedals and straps.

No matter how they're generating that torque they definitely don't want to slip off a pedal going full tilt.

Riding a hardtail I always want clipless pedals because I don't want to have have my ankles at a weird angle just to grip pedals when I go over something rooty.

> When paired with suitable rims, the reduction in rolling resistance of wider tyres more than compensates for the penalty of increased weight and drag.

Unless you include specific conditions you can't really say that a hard, narrow tyre won't be faster with any confidence.

At some point having even wider tyres will only slow you down because the surface bumps don't get any bigger but the cda of your front tyre and rolling resistance due to hysteresis keep increasing.

e.g. a 4" fat bike tyre at 0.5bar is not going to be faster in a velodrome than a 23mm tub at 7bar just because they're wider. If you were riding on snow or cobblestones however...

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

#172

Post by ses1984 »

tuatoru wrote: post #149
Enginerrrd wrote: post #141

Earlier quoted context omitted.

Consider my perspective: I switched to barefoot shoes to prevent problems I didn't have and wrecked my knee to where I had to quit running entirely for ~6-7years. I'm finally able to run now again though but I'm never trying that experiment again.

People go too hard. If you're in your 20s, starting at ten minutes a day and working up to 90 minutes over the course of 18 months is a reasonable rate of change. Tendons and ligaments do not adapt at the same rate as muscles. Nor do articulation patterns.

I never it past twenty minutes and have myself plantar fasciitis with barefoot shoes.

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

#173

Post by culebron21 »

I took jumping stilts classes in 2010-11. They work the same way -- you swing arms and body in the air, *land with straight knees* to compress the spring and preserve the energy, and then fly back up in the air. Maybe they are less efficient than the proposed device, but...

Running in them, even properly like mentioned, was like running a sprint. You were wet and exhausted in half a minute.

Fell from them twice -- once while running, a rubber shoe of the leg that was moving forward, brushed the asphalt, and I fell forward. Despite my arms were ahead, I hit the asphalt with elbows and ribs.

The other time, year later, a rubber shoe broke apart when I landed on it, and the other leg, under much weight, bended slightly off the turning plane -- there was no fracture, but I barely could walk or cycle. It took a week till I could cycle, 2-3 weeks to walk normally and 3-4 months to stop feeling pain.

Overall, it's too exhausting, you can't run in low energy mode. Walking in them is noteably harder and not much faster. You also can't stand straight in them -- must always keep stepping to keep balance, because there are no human feet to balance back&forth.

Another issue is that it puts a lot of load on spinal disks, and some bone/connective tissue conditions forbid this -- you can walk but jumping will cause chronic pain for some time.

Not to mention you can't walk in them in autumn, when asphalt is wet and covered with slippery leaves.

Overall, it's more like downhill MTB -- for skilled and fit, and not scared of a fracture every season.

==== EDIT: Ok, maybe the whole problem with jumping stilts is height. I'd still love to see a mechanical stilts with springs that don't put you that high in the air, but have springs on the sides.

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

#174

Post by moron4hire »

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.

There is no surer way to destroy my feet than to walk around barefoot in even my house.

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

#175

Post by moron4hire »

solumunus wrote: post #155
Forgeties79 wrote: post #130

Earlier quoted context omitted.

Hey there! I don’t know what you’ve done to treat it so far, but I am somebody who went through a year and a half of very painful plantar fasciitis after a few years of moderate pain. I tried every single solution under the sun and am actually “cured”! Some unsolicited input, if you want: 1) Kuru tennis shoes with an insert for PF are excellent. 2) Oofos slippers by my bedside even today. They provide such good relie…

> ultimately had to get my plantar fascia released What does this mean?

Having a surgeon physically cut the plantar fascia muscle.

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

#176

Post by sevensor »

moron4hire wrote: post #126
mikestew wrote: post #114

Earlier quoted context omitted.

I am NOT anyone with relevant credentials, just a lot of running over the last 40 some years in a lot of shoes. That said, I no reason to think that VaporFlys would help with plantar fasciitis. I hypothesize that it's the energy return (which is energy not pounding the legs) is what saves the legs, and I don't know that help plantar problems. And the shoes are designed around running, not walking. Mainly, though, is…

My thinking is that a spring that can provide power also absorbs power. Basically a low-pass filter, like a capacitor. IDK. I've tried the socks, the boots you wear while you try to sleep but can't because they itch too much, and all kinds of shoes. Honestly, I'm at the point where I'll try just about anything.

Anecdata, which I welcome you to ignore: A plantar fasciitis sufferer I know got substantial relief by walking around barefoot in the house at every opportunity. This helped because the tissues in the foot were actually too loose and flexible, which was the root cause of the complaint. The fascia was rolling around all over the place and becoming inflamed as a result. Doctor-prescribed stretching regimens and arch supports had actually made the condition worse. A physical therapist recommended the correct course of action, which was almost exactly the opposite: walking barefoot helped tone and strenghten the feet, and the inflammation subsided.

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

#177

Post by karmakurtisaani »

sib301 wrote: post #166
karmakurtisaani wrote: post #163

Earlier quoted context omitted.

They probably needed their teeth too much.

People fall off bikes and lose their teeth in the process all the time.

Sometimes they even fall just walking on their feet, I've heard.

The point is, these springs look terribly difficult to maneuver compared to bikes. No brakes, not continuously touching the ground, constant movement up and down etc.

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

#178

Post by asoneth »

chrisweekly wrote: post #103
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

Depends on the distance, right?

Over short distances (up to about 800m) a cheetah's sprint speed of nearly 100kph dominates, true. However, because they only maintain that for up to 30s, an augmented human moving at 75kph would be less than 10s behind at that point and might be able to catch up over slightly longer distances. I'm unsure the exact distance as I don't know offhand what running speeds a cheetah can maintain for longer than 30s and I'd also assume that cheetahs have better dodging agility than a human with giant springs strapped to their legs (and as per above hopefully some safety gear).

But I stand by my assertion that I want to imagine such a scenario.

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

#179

Post by kcplate »

moron4hire wrote: post #109
mikestew wrote: post #36

Earlier quoted context omitted.

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.

Im sure after that much time you have your own remedies but for me —-a golf ball, tennis ball, and on severe pain days a frozen water bottle under my desk does wonders when mine is inflamed. Just take off a shoe and roll your foot over each rotating golf, tennis, water bottle.

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

#180

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…

Actually, you're right, now I recall it better, you swing arms in the bottom point, to compress the spring better. Waving arms in the air does not help.
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