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1

If all you did was drink distilled water, it would not be terribly healthy for you. But most people eat as well - and that combination probably includes "healthy" minerals. Unless you binge-drink distilled water without any food, it's unlikely to cause serious health effects. Having said that - ions are pretty small - certainly smaller than 15 nm. But their ...


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Work isn't neccessary to move The statement "To move we need to perform work on our mass" is false and misleading. We need to perform work in order to accelerate our mass, and we need to perform work to overcome various resistance forces, but in general things can move an arbitrarily large distance with arbitrarily small amounts of work. Top speed is ...


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This is a matter of efficiency: If you keep your knees slightly bent for a long time, you'll get tired, although you are not moving your body at all. If you just stand on one stroke of your bike, when it has slightly past the highest point, you will push it down creating movement. Even if you kneel is not bent, because is gravity what pushes it down. If ...


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faster long-distance runners hit ~20 km/h (marathon records) while fastest cyclists can do ~40 km/h So what causes the difference? different cardiac activity? different power output during these activities? more energy loss for running? friction? impact of the bike gearing? something else? That is the main negative factor, than ...


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This would be perhaps better off as a comment, but my reputation says I can't yet comment. All the other answers get the physics aspect right, but there is more to it from the biology point of view which might help the total average: you can rest on a bicycle more effectively. You can rest (or at least save some energy) going downhill (while actually ...


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As you say, "to move we need to perform work on our mass". The work we produce, however, is not the limiting factor when we run. It is how efficiently we convert work to forward motion. The bicycle - by design - is a more efficient device to achieve this than only our legs. The deficiencies of running are outlined in Floris' answer.


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Because work done to pull a pulley is less and the wind resistance is less while cycling than while walking because of the aerodynamic shape of the cycle. While cycling you are sitting and while walking you are standing which requires more energy. The friction between the tires and the ground is less than our legs and ground.


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I would venture to say that if you would notice that it takes longer to build up momentum on a bike as opposed to running, this is because energy needs time to store in the wheels due to the wider circumference they have over the cycles we make with our peddling (which is roughly equal to the steps we make while running) and for every cycle our peddle makes ...


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I imagine you are getting the benefit of the mechanical advantage of the bike's gearing. On top of that you have less resistance between the tire and the road surface. I think those two will account for most of the difference.


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It is all about the loss of energy during each stride - the tendons store some energy, but not a lot. A kangaroo and a greyhound, for example, have far more efficient elastic storage in their legs / tendons, allowing them to achieve (and maintain) greater speeds with less effort. Key phrase from the abstract in that reference: elastic storage of energy ...



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