Love this article. Especially the part on how they managed to measure protein uptake in the muscles.
https://www.outsideonline.com/2259366/four-laws-muscleQuote:
infusing 40,000 euros’ worth of amino acids, specially “labeled” using a rare and trackable isotope, into a cow. Then they milked the cow and, 24 hours later, slaughtered it. The result: milk and beef that can be tracked with painstaking precision as it progresses from a person’s mouth to their biceps by taking frequent samples of blood and biopsied muscle tissue in the hours after a meal.
