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Running Speeds
91–100 of 195 posts
Re: Running Speeds
#92I'm not sure this analysis is as surprising or meaningful as it might seem at first sight. In the end I think what this tells us is that in the general population there are many distinct subpopulations with different distributions of running speed. I would expect that if you start conditioning on things (e.g. gender, age, level of fitness) things start looking a lot more normal, rather than log-normal. You might not…
If I'm not wrong you can't obtain a lognormal as a mixture of Gaussian distributions. The processes that generate these distributions are completely different. Gaussian distribution arise when the factors are additive, and lognormal when factors are multiplicative, so these are two completely different distributions. The same way I don't think you can get a normal distribution just by conditioning on an exponential d…
I was thinking about this and how you might get a lognormal from normals. Peer comments I think have good suggestions.
The thing is a while back I took a look at the times achieved by competitive athletes at the 100m dash (from worldathletics.org), and they looked normally distributed. Intuitively that made sense to me - many other human attributes are normally distributed, so why not this?
Re: Running Speeds
#93I've often wondered how exactly I might increase my sprint speed, in terms of form. I've never met a sprint trainer, so all I can do is just try to naturally sprint, but I'm clearly not very fast and never was. But somehow I don't even know what the fundamentals are. What do you need to do to be fast? The other amazing thing is that marathon runners seem to be faster than I can sprint, and I really don't get how they…
I was a coach once. There are two mistakes where most people can benefit a lot if they fix them. They are somewhat connected. 1) Foot strike to far in the front as in [1] and [2]. This mostly happens because people want to run fast, and therefore take longer steps. It is very counterproductive though. A longer steps lowers your center of gravity, and because the foot strikes the ground very far in front of the COG, y…
kudos using that guy who lost to The Freeze as an example
it seems link [3] with Bolt's extension is broken
Re: Running Speeds
#94I've often wondered how exactly I might increase my sprint speed, in terms of form. I've never met a sprint trainer, so all I can do is just try to naturally sprint, but I'm clearly not very fast and never was. But somehow I don't even know what the fundamentals are. What do you need to do to be fast? The other amazing thing is that marathon runners seem to be faster than I can sprint, and I really don't get how they…
As someone else mentioned, there’s plenty on YouTube to help re form. That said, I’m helping my elementary aged kids improve their middle distance running (I’m no sprinter, so I can’t help there) and the two basic tips I’ve been using to help them: - practice barefoot occasionally, and pay attention to how your form changes. You’re more likely to just naturally land on your forefoot when you’ve no shoes on. Now try a…
> practice barefoot occasionally
I would add that “barefoot” means, literally “barefoot”. I had convinced myself that “barefoot shoes” would be sufficiently the same because I was running outdoors and didn’t have the guts to do actual barefoot. I recently bought a new Assault AirRunner (curved motorless / manual treadmill) and run on it actually barefoot. The difference in my running form and sudden introduction of new muscle soreness makes clear how even barefoot shoes affect form.
Off-topic side note/rant: it is incredibly annoying how the Apple Watch becomes wildly inaccurate when on treadmills. GymKit has been out for years and has no - zero! - uptake among home treadmills and even shockingly low among commercial treadmills. And shame on Assault Fitness for creating an expensive, commercial level manual treadmills with an app that can see the data via Bluetooth from the treadmill, and failed to integrate HealthKit to sync the data. Wild decisions.
Re: Running Speeds
#95I have what may be a silly (or even ridiculous) question: Why do recreational distance runners care about speed so much? Background: I went through a phase of long-distance recreational running - I ran lots of half-marathons, marathons, and even the Disney Goofy Challenge for a few years (half marathon on Saturday, full marathon on Sunday). It was all fun! Training was satisfying, the running itself was tough but rew…
Why did you care about the distance so much?
Re: Running Speeds
#96I've often wondered how exactly I might increase my sprint speed, in terms of form. I've never met a sprint trainer, so all I can do is just try to naturally sprint, but I'm clearly not very fast and never was. But somehow I don't even know what the fundamentals are. What do you need to do to be fast? The other amazing thing is that marathon runners seem to be faster than I can sprint, and I really don't get how they…
I was a coach once. There are two mistakes where most people can benefit a lot if they fix them. They are somewhat connected. 1) Foot strike to far in the front as in [1] and [2]. This mostly happens because people want to run fast, and therefore take longer steps. It is very counterproductive though. A longer steps lowers your center of gravity, and because the foot strikes the ground very far in front of the COG, y…
1 rings super true to me - the most counter-intuitive thing to me in distance running was to take more steps to go faster. 180-190rpm is usually where I’m at for 2:55ish marathon times, whereas when I started, I thought I needed to be at like, 160, but with a longer stride distance.
It’s more interesting because I sprint “properly”, but my brain just flipped when I started going further.
Re: Running Speeds
#97>height and weight, fast- and slow-twitch muscle mass, cardiovascular conditioning, flexibility and elasticity, and probably more. When we try to figure out how to measure someones speed (say to compare Usain Bolt to another high quality sprinter) we will look at factors like height, stride length and strength. But in terms of all the factors that need to be measured to describe the function of someones running speed…
That seems, at least to me, a pretty egalitarian and optimistic view. I mean, the teenager is basically as good as the Olympian in your example, qualitatively. If the peak of skill is only 10% higher than a talented amateur with some training, we should probably have a more equal income distribution.
Re: Running Speeds
#98I have what may be a silly (or even ridiculous) question: Why do recreational distance runners care about speed so much? Background: I went through a phase of long-distance recreational running - I ran lots of half-marathons, marathons, and even the Disney Goofy Challenge for a few years (half marathon on Saturday, full marathon on Sunday). It was all fun! Training was satisfying, the running itself was tough but rew…
People gain a natural satisfaction out of seeing progress in pretty much allof their pursuits, leisure or otherwise. Catching a bigger fish, closing a bigger deal, growing bigger muscles, cooking a more elaborate meal, etc.
And to your point, many of them want some type of objective “score” they can use to measure that progress.
Re: Running Speeds
#99Earlier quoted context omitted.
If I'm not wrong you can't obtain a lognormal as a mixture of Gaussian distributions. The processes that generate these distributions are completely different. Gaussian distribution arise when the factors are additive, and lognormal when factors are multiplicative, so these are two completely different distributions. The same way I don't think you can get a normal distribution just by conditioning on an exponential d…
Say you get a lognormal by combining five gaussian-distributed factors (as in the past). Then you condition on four of those factors. The remaining factor, and hence your overall result, will be gaussian. Now, maybe in real life there are far too many factors and we're only holding a few constant so the math doesn't apply, but I do think the math is valid.
Good point, I was wrong. However, it can also happen that the factors are not gaussian, and still the multiplication would follow a lognormal distribution by the CLT. So saying that "if you condition on enough factors the distribution will be normal" requires the assumption that the factors are normally distributed.
Re: Running Speeds
#100Earlier quoted context omitted.
I can say I’ve worked through four of his books from front to cover. You’re right. The learnings are on top of (some) math. In my case actually quite a lot of math post-high school. But I think a 14 year old could finish the books as well, or at least 90%. My eldest is 10. He is good at math because we do math games all the time. I can’t get algebra to sink in properly yet. Doesn’t really click in the time we have an…
> can’t get algebra to sink in properly yet. Doesn’t really click in the time we have and with the teacher he has (me). But in Python he is giving variables a name all the time. Perhaps there is something about programmatic math that helps, not hinders education. On the hinders side though, I can understand it being confusing to try to grasp: y = x + 2 As being sort of 'constantly updating', referring to x in abstrac…
The opposite confusion is actually something that really surprised me, working with beginner programmers for a while. The mistake that y=2+x should set up some constant relationship where y updates along with x should be expected for people who’ve been doing math their whole lives and not programming, but it is pretty confusing to figure out their confusion the first time.