The science existed. The tool didn't.
Eccentric loading — the slow, controlled lowering phase of a movement — is the approach that underpins the clinical guidance for tendinopathy. The gap was never the science. It was doing it right, at home.
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What "eccentric loading" means
Muscles and tendons work in two directions: shortening under load (concentric) and lengthening under load (eccentric). The eccentric phase — controlled lengthening — is the part that progressively conditions a tendon to tolerate load. It's a well-established exercise principle, not a gadget trick.
For the elbow, that means loading the wrist extensors and their tendon through a slow, deliberate lowering, then resetting with the other hand. Simple in theory. The details — the right load, a genuinely controlled tempo, done consistently for weeks — are where it usually falls apart at home.
The FlexBar showed the way
The idea of using a flexible bar to load the elbow eccentrically has been around since 2010, and it worked — the rubber resistance bar proved that eccentric loading of the elbow could be done with a simple home tool. It was a genuinely good idea.
But a rubber bar can only do so much. The load isn't measured. The tempo isn't paced. Progress isn't tracked. You're guessing — and guessing is exactly what a rehab routine can't afford. The FlexBar proved eccentric loading works at home; Rebow is what that idea should have become.
The home-implementation gap
The right load
An adjustable moment arm sets a precise, repeatable load — and the app reads it back in newton-metres. No more "about right."
The right tempo
The controlled lowering only works if it's actually controlled. The app paces each rep so the eccentric phase is real, not rushed.
The right consistency
Tendons respond over weeks. Rebow logs every session so you — and your physio — can see the trend, not just today.
Eccentric loading is the approach that underpins the guidance clinicians already give. Rebow's contribution isn't a new claim about outcomes — it's making that established method measurable and paced outside the clinic.