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Running Speeds

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Re: Running Speeds

#181

Post by OJFord »

bee_rider wrote: post #100
OJFord wrote: post #19

Earlier quoted context omitted.

> 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.

It had never really occurred to me before writing that comment. Now I think it's really curious that not only there is that stark difference, but also that it's common across all programming languages (I'm not counting Excel, sorry) I'm aware of.

It might be tempting to think it's procedural vs declarative, but it's not really, you could procedurally evaluate that y should now be maintained to have such value. Admittedly you can't really do it any other way on declarative terms. But what allows you to do computation like that? Datalog maybe?

I'm ignoring Matlab/Octave/etc. because I'm not that familiar and of course (I assume) they work more like math. What's interesting is that everything else seems to do it differently; I'm not sure why or how that happened. Is it as simple as an early limitation (in terms of early computation and compilers) that stuck?

Re: Running Speeds

#182

Post by iamacyborg »

morepork wrote: post #176
iamacyborg wrote: post #175

Earlier quoted context omitted.

Right, track surface is a big differentiator, let alone shorter indoor 200m tracks. There’s a big difference in shoe technology between road and track too, primarily in terms of the amount of super foam allowed which in terms of the shoe is generally what seems to provide the most benefit.

For sprints in particular, the spikes make a decent difference on the track, more so for elite athletes as they need the extra traction more

Yep, but for longer distances the track has a better energy return than running on the road.

Re: Running Speeds

#183

Post by mikestew »

onetimeuse92304 wrote: post #180
jmye wrote: post #178

Earlier quoted context omitted.

I will say, in defense, that the foam and some of the carbon plates, do substantially help with recovery. I use an older pair of VaporFlys for that reason - my feet and calves feel much better the day after a big race. That said, the effect, for me, only matters at full marathon distance. I don’t see any point in wearing any of those shoes for the average weekend 10ker.

You can buy good recovery shoes/slippers for small fraction of the price though...

I’m sure those make for horrible race shoes. I think you missed parent’s point.

Re: Running Speeds

#184

Post by wly_cdgr »

nlh wrote: post #68

I 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…

Cos I like beating people like you

Re: Running Speeds

#185

Post by saberience »

patrick0d wrote: post #171
michaelt wrote: post #169

Earlier quoted context omitted.

I actually took that time from [1] which was set in 2017. If you prefer, let's consider California, population 30 million to Scotland's 5 million. According to [2] for the "Boys 100 Meter Dash Varsity" 10.7 would put you among the 20 fastest in the state, although it wouldn't quite get you into the finals (which needed a time of 10.63) Fastest 20 in a state of 30 million doesn't sound "pretty achievable for someone w…

I said a good teenager might run 10.7 and you have found a list of teenagers (I don't know how old they are) that can do just that. Very few people sprint after they leave college but if they spent time becoming stronger and more physically mature then 10.7 would be quite achievable - even a good highschool runner can run that time. My original point being that people can run this fast and that if they do they would…

20 out of 40M people doesn't seem like a horde to me. In fact, it seems like the chances of any teeneger running 10.7 is vanishingly small, around the chances of winning the lottery.

So going back to your statement, it's really more like saying, "One in a million teenagers is able to run within 10% as fast as the fastest man in the world. But that 10% barrier is incredibly difficult or almost impossible to cross."

Re: Running Speeds

#186

Post by cafard »

nlh wrote: post #68

I 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…

As people have said, once you know that you can run the distance, why not see whether you can run it faster? Having said that, I never timed the runs I did by myself or with friends.

Re: Running Speeds

#187

Post by remram »

js2 wrote: post #122
nlh wrote: post #68

I 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 do recreational distance runners care about speed so much? Some of us to achieve our PB. Others to BQ: https://www.baa.org/races/boston-marathon/qualify Some of us also engage in longer distances to find our limits. If you want a mostly chill crowd of runners, start running ultras. Speaking of finding limits, this past weekend the backyard ultra record was broken again. It now stands at an amazing 108 hours (th…

PB = personal best

BQ = something qualify?

ultra = ultramarathons, races longer than 42.195 km / 26 mi

Re: Running Speeds

#188

Post by alok99 »

remram wrote: post #187
js2 wrote: post #122

Earlier quoted context omitted.

> Why do recreational distance runners care about speed so much? Some of us to achieve our PB. Others to BQ: https://www.baa.org/races/boston-marathon/qualify Some of us also engage in longer distances to find our limits. If you want a mostly chill crowd of runners, start running ultras. Speaking of finding limits, this past weekend the backyard ultra record was broken again. It now stands at an amazing 108 hours (th…

PB = personal best BQ = something qualify? ultra = ultramarathons, races longer than 42.195 km / 26 mi

BQ = Boston Qualifying, I think. I.e. running better than the standard for men/women in the Boston Marathon

Re: Running Speeds

#189

Post by tgv »

suavesito wrote: post #39
tgv wrote: post #31

Earlier quoted context omitted.

Because it fits by multiplying random variables. It cannot explain why records are improving, i.e. why Usain Bolt didn't live 100 years ago.

It can explain it. Better training and better equipment are (at least) two variables that improve people timings. Maybe a century ago there was an Usain Bolt, just didn't had neither the proper training, nor equipment, and those low factors avoided better timings.

Except the model was fitted on people from the same period in the same region.

Also, Ethiopian runners would be a counterargument. It's just reading way too much in a model that probably was there before the data. Seeing how everybody defends it as "learning", the example was sought to be described by the model.

Re: Running Speeds

#190

Post by bee_rider »

OJFord wrote: post #181
bee_rider wrote: post #100

Earlier quoted context omitted.

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.

It had never really occurred to me before writing that comment. Now I think it's really curious that not only there is that stark difference, but also that it's common across all programming languages (I'm not counting Excel, sorry) I'm aware of. It might be tempting to think it's procedural vs declarative, but it's not really, you could procedurally evaluate that y should now be maintained to have such value. Admitt…

In matlab, the = sign is an assignment operator. I think it is really common because load/compute/store is what the hardware does, and so languages tend to be built around computing a value and then assigning it.

You could, I guess, in any language that allows operator overloading (Python would be a good one) define operators that actually return a function for computation, guess. This just seems like a really complicated way of defining a function, though.

Or possible a template library like Eigen could be thought of in terms of “building a computation.” Maybe CUDA has something like this? I’m not sure, at all.

An aspect for my case specifically, which is probably not a coincidence, is that I usually work with Electrical Engineering students. They’ll typically have seen some very light Verilog in some of their intro classes. I’m definitely not a Verilog expert, but you can use it to define combinatorial circuits—in that case you are literally describing the wires and gates that the computation flows through, so the left hand side does change based on the right hand side, continuously. At least until you write to a clocked register. And of course in a real circuit, there’d be some signal propagation time…

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