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by WJW 1463 days ago
500W is an extremely high number as well. Pro cyclists can reach up to 400 Watt in short bursts, untrained people typically can't maintain more than 100-150W for long. We really use quite a lot of energy when measured in how many humans it would take to provide that much energy "manually".
2 comments
anon_123g987 1463 days ago
While it's true that the power of a human is not much (certainly not enough to power a house), but we have a lot of energy. Most of us carries at least 1 kg (~2 lbs) fat, which contains ~37 MJ of energy. For comparison, a stick of dynamite has ~1 MJ of energy.

https://en.wikipedia.org/wiki/Fat#Biological_importance

https://en.wikipedia.org/wiki/Dynamite#Form

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trelane 1462 days ago
Why stop there? The matter itself is energy, so combine a human with an anti-human....
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BizarroLand 1461 days ago
Sweet oblivion looks just like me
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Merad 1462 days ago
> Most of us carries at least 1 kg (~2 lbs) fat

It's a lot more than that. Even a fit (healthy, but not necessarily peak athletic shape) adult man will have about 15% body fat, 20% for a woman.

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yetihehe 1463 days ago
> Pro cyclists can reach up to 400 Watt in short bursts

I heard pro cyclists can reach up to 2kW. I managed to make 500W on a rowing machine for 5 minutes, but I'm a couch potato. I believe 400W is a normal rate for cyclists. When you are sitting, your body already produces about 100W of heat.

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SubuSS 1462 days ago
So cyclists measure their capability in terms of FTP - essentially what power output they can maintain at full throttle for an hour.

This hugely depends on body weight / gender / training levels etc., body weight being a big deal since that’s what you’re transporting. So the other way folks measure output is W/kg of body weight.

A beginner adult male will be in the 100-200W zone, around 0.5-1.5 W/Kg. Usually anyone can train themselves into the 200-300 (3-4 W/Kg) zone which is the recreational pace - the groups of cyclists you see on the road. Beyond 300 ftp (150lb body weight) (4-5 W/kg) you’re reaching race pace. The ones you see on screen have upwards of 5-6 W/Kg FTP output. They obviously have other constraints around putting this output at the end of a 200km ride for 20 mins etc as well, which makes it extra hard.

Finally we come to the KW numbers - all these folks have two kinds of muscles (fast twitch and slow twitch). The sprinters are saddled with a higher proportion of the kind of fibers that can allow huge spurts of power - they put out about 1000-1500W for about 5-10s. These are probably what you’re thinking of. This is pretty much an end of ride (or a sprint section) empty your tanks effort.

Semi related tidbit: track cyclists are a middle kind of beasts here: they put 600-1000W for a couple of minutes but don’t have to worry about riding 200kms to get there.

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