Research

Mixed

Heavy resistance training increases patellar tendon stiffness without changing the tendon modulus (material property), suggesting structural hypertrophy rather than just material stiffening.

Heavy training makes your tendons stiffer, but this is a good adaptation. It happens because the tendon gets thicker (hypertrophy), not because the material itself changes quality. This thicker, stiffer tendon handles load better and may be less prone to injury.

GoodSupportsHIGH confidence
PT stiffness increased in heavy-legs (P < 0.05) but was unchanged in light-legs. Modulus remained unchanged in both legs.
M. Kongsgaard et al. · Acta Physiologica · 2007

Why this rating

Robust measurement of mechanical properties using ultrasound and force data, consistent with the CSA findings.

Source

Region specific patellar tendon hypertrophy in humans following resistance training

M. Kongsgaard et al. · Acta Physiologica · 2007

DOI 10.1111/j.1748-1716.2007.01714.x

rct · n=12Cited 383×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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