The Thin Air Secret: How Where You Train Has Quietly Become as Important as How You Train
Kenya and Ethiopia have produced a staggering share of the world's best distance runners for decades, and for a long time the explanation felt almost mystical. Then sports science caught up and found something far more concrete — geography. The elevation advantage that East African runners grew up with has since become something wealthier nations try to buy, sparking a quiet revolution in how Olympic athletes prepare and who gets to compete at the top.