Patellar tendinopathy - Berlin method after months of heavy slow resistance
I have a long 15 years of patellar tendinopathy from jumping in my early 20s, probably 7 of those in pain as the other years I didn't do any physical activity. For the last 20 consecutive months I've been doing heavy slow resistance mostly 3 times a week. I do have a history of regular (nothing serious) strength/hypertrophy training for maybe 5 years, mostly in my early 20s (I'm 36 now).
Symptoms are stable, I wake up without pain and start to feel a little pain during the day and more pain during the warmups before HSR which goes away after a few reps. Little pain after workouts which vanishes the next day.
This is pretty much the last 10 months and I'm having a hard time trying to progress from here. Strength has plateau, I do single leg extension 4 sets of 4 or 5 reps with around 225 lb / 100 kg 3 seconds down, 1.5 seconds up (I'm 6'5 / 195 cm, 245 lb / 110 kg). I can no longer increase the weight and do more than 3 or 4 reps because of my strength, not my tendon.
I can jump, sprint with some some intensity, maybe 75% but anything above that will cause flare ups, same with heavy deep squats with a little bounce.
This hasn't changed for a long time and lately I've been reading about berlin method. What I think my situation is, is that I can no longer create tendon adaptations because of my strength (which IMO is decent but not enough to move the needle further) and the berlin method seems to fit in this case, because an ISO at 90% MVC for 3 seconds will for sure produce more force than the 100 kg I do in the single leg extension, meaning it will strain the tendon more = more adaptations.
Does this make sense or am I missing something in this picture?