Jumper's Knee: Why Progressive Tendon Loading Has Overtaken Eccentric-Only Programs

Eccentric decline-squat protocols dominated patellar tendinopathy rehabilitation for years, despite requiring athletes to exercise into pain and showing mixed results in competitive, in-season populations. Breda and colleagues' randomised clinical trial, published in the British Journal of Sports Medicine in 2021, tested a pain-guided alternative built on staged, progressive loading.

The investigators randomised athletes with clinically diagnosed and ultrasound-confirmed patellar tendinopathy to one of two 24-week programs. Progressive tendon-loading exercise therapy (PTLE) moved through four criteria-based stages: isometric holds, isotonic strength work, explosive and energy-storage loading, and finally sport-specific training, with progression permitted only when pain remained within an acceptable range. Eccentric exercise therapy (EET) followed the established approach of single-leg decline squats, performed into pain, followed by sport-specific exercises.

At 24 weeks, the PTLE group improved by roughly 28 points on the VISA-P — the standard measure of patellar tendon symptoms and function — compared with roughly 18 points in the EET group, a statistically significant difference favouring the progressive approach. Return to sport was also higher with PTLE (43% versus 27%), while satisfaction and adherence were similar between groups. Notably, neither program fully resolved symptoms for most athletes within six months, reinforcing that patellar tendinopathy recovery is a long game.

For practice, this trial supports structuring rehabilitation as a criteria-driven progression from isometric through isotonic to energy-storage and sport-specific loading, using pain as a guide for progression rather than a target to push through. It also helps set realistic timelines: meaningful improvement builds over months, and return to full training should be earned through tolerance of progressively demanding tendon loads.

Key findings

• Athletes with clinically diagnosed, imaging-confirmed patellar tendinopathy were randomised to progressive tendon-loading exercises (PTLE) or eccentric exercise therapy (EET).
• PTLE progressed through four stages — isometric, isotonic, explosive/plyometric, and sport-specific loading — with progression guided by acceptable pain levels; EET centred on single-leg decline squats followed by sport-specific work.
• At 24 weeks, the improvement in VISA-P score (a validated symptom and function measure) was significantly greater with PTLE (about 28 points) than with EET (about 18 points).
• Return to sport was higher in the PTLE group (43% vs 27%), with no significant differences in satisfaction or adherence between groups.

Clinical relevance

Patellar tendinopathy is common in jumping and change-of-direction athletes, and this trial gives clinicians a clearly staged, pain-guided loading framework with better outcomes than the older eccentric-only standard.

Prepared by the Volt Health team as an educational summary of the cited publication. It is not medical advice; assessment and treatment decisions should always be made with a qualified health professional.