This question is about Nutrition and Running
Yes, milk can serve as a quick and easy post-workout snack for runners, however, it’s not entirely necessary for all runners to drink milk.
One 8-ounce (1 cup) glass of cows’ milk provides 8g of high-quality protein which is important after exercise because it promotes muscle synthesis [ 1
Cow’s milk can also help runners strengthen their bones, and replete minerals lost through sweat such as calcium, magnesium, and potassium. Find more information on optimal nutrition for runners here
[1] James, L. J., Stevenson, E. J., Rumbold, P., & Hulston, C. J. (2019). Cow's milk as a post-exercise recovery drink: implications for performance and health. European journal of sport science, 19(1), 40–48. https://doi.org/10.1080/17461391.2018.1534989