Hot answers tagged biology
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 ...
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 ...
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.
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 ...
Only top voted, non community-wiki answers of a minimum length are eligible