panuma

I see Birkenstocks as orthopedic shoes that shouldn't be worn on a healthy foot. Think what happens if you push a brick in an arch from below. Huaraches, Luna sandals etc. are a better option healthwise, people run ultramarathons in them and the design has thousands of years of history.

Superior time perception for lower musical pitch explains why bass-ranged instruments lay down musical rhythms http://www.pnas.org/content/111/28/10383

Speed of sound in e.g. wood is 10 times faster than in air. So an electric guitar player with 3.4m cord to the amp can feel a latency of 1ms for low frequencies through the stage and his feet. Humans have more rhythmical precision with said low frequencies. Symphonic orchestras are not known for their tight rhythm.