In this rerun episode, we dig into the science behind what's happening inside our bodies with registered sports dietitian Ashley Reaver. Ashley highlights five key biomarkers that endurance athletes should pay attention to—explaining why they matter, what healthy ranges look like, and what steps we can take if our numbers are off. From performance to recovery, these biomarkers influence how well we train and how resilient we are to stress and fatigue. Ashley also shares practical strategies athletes can use to optimize their nutrition and overall health. With her background as a private practice dietitian, UC Berkeley instructor, and lead nutritional scientist at InsideTracker, Ashley brings both scientific depth and real-world application. Whether you're chasing new PRs or aiming for long-term health, this conversation offers valuable insights every runner can put into practice. Check out her private practice

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