Running marathons on GLP-1 drugs brings tough side-effects for some

As weight-loss drugs such as tirzepatide become more common, some endurance runners report struggling with side-effects. One experienced marathoner said she felt nauseous and could not keep down energy gels while racing days after her first dose. Use of GLP-1s for weight loss has risen from 3% to 11% in two years, and sports dietitians are increasingly advising runners who take them.