sciencehabit writes "A quick visit to Monty Python's Ministry of Silly Walks shows just how many ways humans (or at least British comedians) can think of to travel from point A to point B. So why don't we high kick our way to the bus stop or skip to the grocery store? New research suggests that there may be a deep biomechanical reason governing the gaits we choose in different situations. In short, people consistently choose to walk when they need to travel slower than 2 m/s to reach their goal in the given time; when they needed to move about 3 m/s or faster, they ran. But in between—in 'the twilight zone between walking and running'—people tended to mix the two gaits, minimizing their energy expenditure. The findings could help scientists design better prosthetic limbs and even build more human-like robots"