RED-S comes up more and more in climbing: in athlete interviews, in federation policy, in the occasional hard conversation at the gym. It's also widely misunderstood, when it's understood at all. So here's the plain-language version every climber should know.
The definition
RED-S stands for Relative Energy Deficiency in Sport. The concept is simple: your body has a total energy budget, and training draws on it heavily. If the fuel coming in doesn't cover both the training and the baseline work of being a functioning body, the body starts making cuts. It doesn't cut evenly, and it doesn't cut where you'd choose.
The systems that get downgraded read like a list of things athletes care about most: recovery, bone maintenance, tendon repair, hormone function, immune defense, focus, mood. For women, disruption of the menstrual cycle is a common and medically significant signal. For men, the hormonal effects are quieter but just as real. For everyone, the injury risk climbs while performance falls.
The name matters: it's relative deficiency. You can eat what looks like a normal amount and still be deep in deficit if the training load is high enough. Plenty of athletes land in RED-S without any intention of restricting.
Why climbing has a particular problem
Climbing carries a strength-to-weight culture, decades of "lighter = stronger" folklore, and a competitive history that pushed some of its best athletes into exactly this hole. The sport's own governing bodies have acknowledged the problem, and screening and policy around athlete health have been tightening at the elite level in recent years.
But RED-S is not an elite problem. The same folklore that damaged pros circulates in every gym, and a weekend climber cutting food while adding sessions runs the same physiology as a World Cup athlete doing it. The badge doesn't matter. The energy budget does.
What it looks like, pattern-level
No single sign proves anything, but the cluster is recognizable: performance stalling despite consistent training, recovery slowing, repeated small injuries (fingers, tendons, and stress-related bone issues especially), getting sick more often, mood and psych flattening, sleep degrading, and for women, cycle changes. The pattern usually builds gradually, which is exactly why it gets misread as a plateau, a motivation dip, or "just getting older."
The good news
RED-S is fixable, and the fix is the opposite of complicated: the energy budget has to balance. More fuel, sometimes moderated training for a stretch, and support from people who know the territory. Athletes who address it typically get better, not just healthier. The strength was never gone. It was underfunded.
What to do with this
Two things. First, for yourself: if the pattern above reads uncomfortably like your last year, take it seriously and talk to a professional, ideally a sports dietitian or a sports-medicine doctor. Second, for your community: retire the "lighter = stronger" lines when you hear them, and normalize eating to fully fuel.
This post is educational, not medical guidance. If it raised something personal for you or someone you climb with, a qualified professional is the right next step, and the National Alliance for Eating Disorders helpline can help you find support.
