Reply to the letter : To consider the exercise density in the dose–response relationship: the idea is promising, the operationalization tricky! - Fabian Herold; Liye Zou; Paula Theobald; Patrick Manser; Ryan S. Falck; Qian Yu; Teresa Liu-Ambrose; Arthur F. Kramer; Kirk I. Erickson; Boris Cheval; Yanxia Chen; Matthew Heath; et al. (European Journal of Applied Physiology, 2026)