Kneeling training

Getting old is compulsory - getting frail is optional

Many people say they cannot kneel at all let alone on a surfboard.

This can be fixed.What you need to be able to do is a kneeling tibialis interior stretch. This is covered in the 12th minute of the video.This video from Unity Gym tells you how to work up to this. Do all the foot and ankle exercises. Before you go surfing, you may have to build up with these exercises over weeks or months, but it is worth it.
Foot And Ankle Strengthening
[FULL WORKOUT & STRATEGY]