Can you get a "second wind"? Is it real?
Dr. William Roberts with the University of Minnesota Medical School and The American College of Sports Medicine along with Dr. Cara Hall from Keck Medicine at USC explain the "second wind" phenomenon.

Why are some English word spellings so weird? Why is there a "k" in knife?! A "b" in doubt?! Our favorite linguistics professor, Jaye Padgett at UC Santa Cruz, is back to answer.

And, why do we get gray hair?
We find out from Dr. Sandy Johnson, board certified dermatologist at Johnson Dermatology in Fort Smith, Arkansas.