I have been repeating the weeks 1-4 of planche leans several times now, working on increasing the lean. This is an exercise which is nothing like anything else I have ever done before, so I found myself initially very weak, finding even a little bit of lean very demanding. I have gradually been able to increase the lean so it is about right now (though it's a bit hard to judge the course video because it is filmed from an angle).
However, I have also developed some kind of overuse injury. I have been a bit sore sometimes, but since the last workout, it became a real, persistent pain, which I can feel throughout the day. I have pain between the finger bones inside my left hand, along the left lower arm and at the left shoulder. I have felt a bit sore also on the right side at times, but not chronic like this. (My shoulders are visibly asymmetric, my left side being higher, which could explain the difference.)
I am taking this week off, but I am wondering how to approach planche leans in a fashion to prevent this from happening again or becoming chronic. I think if I simply push through the mastery template, I will be able to increase the hold times, but I think I will end up injured. What should I do instead? I doubt the planks will help because they don't put any stress on these weak points which are failing me in the lean.
I can think of many alternatives, like reducing the lean and staying on low hold times and increase the amount of lean more slowly. Or should I do long, light holds?
Any advice on the best approach would be most appreciated.