Answer:
UV intensity predicts the skin color of indigenous populations. Stronger UV radiation is correlated with darker skin color. Data suggest that variation in human skin melanin production arose as different populations adapted biologically to different solar conditions around the world.
Explanation:
Answer:
b. The foot and ankle should be pointing straight ahead in a dorsiflexed position when it hits the ground
Explanation:
Dorsiflexion is a movement in the ankle where the toes point in an upward direction allowing for correct foot strike if done properly at approx. 15 degrees. As you run, dorsiflexing your foot puts it in an ideal position to absorb the shock of the landing while simultaneously tensing your muscles to spring forward into the next stride which allows a reduced ground contact time per stride, allowing you to run faster and more efficiently.
If a runner has poor dorsiflexion they may experience a ‘loose’ or ‘floppy’ foot due to relaxation at the ankle joint which results in striking the ground through the toes which causes poor force distribution resulting in injuries such as shin splints and runner’s knee.
