This article by Hollis Molloy, trainer and MetFix Academy staff member, explains why HbA1c should be viewed by coaches as more than a diabetes screening tool—it’s the visible tip of a much larger glycation “iceberg.” HbA1c reflects a 90-day average of blood glucose exposure, but glycation damage accumulates for years in slow-turnover tissues like nerves, joints, and vascular walls, quietly eroding performance, recovery, and resilience. “Normal” or borderline A1c values can still coexist with significant underlying tissue damage, particularly from fructose-driven glycation that A1c does not capture. Framed as a coaching metric rather than a medical diagnosis, rising A1c becomes an early warning signal trainers can act on nutritionally—well before metabolic decline shows up as disease.

https://brokenscience.org/hba1c-and-why-trainers-should-care-about-glycation/