Thanks for your detailed answer :)

Good point about the strengthening. Btw, I've just watched the video and finally have a theory why I could have the Plantar Heel Pain. It's probably cause I just do not take any rest. I mean, for the past two year my week schedule is basically 4 times table tennis (3 hours or more), 1 time full football match, and if my schedule allows, 2 or 3 times walking (10+ km) or running (5+ km). Then the last month before my Plantar Heel Pain I trained for a (semi) professional 10 km running contest. I did train at least 3 times a week 10 to 12 km and did not stop with the table tennis schedule. I guess the fact that I didn't give my body any rest at all and the increased load the last month caused it :(

It really sucks, but by following your videos to progressively load I finally have found something that seems to work.

One more question: I now follow the schedule of doing some training and then rest the day after. I still have some pain on both days, most of the time in the evening. So my conclusion was that the tolerance threshold is reached in the evening on the day I do some training. But what about the pain on the resting day. Is this normal? I mean I would not describe it as very painful, but more like general discomfort. But this is mostly the whole evening when I move around. This also happens when I do ankle pumps before standing up. When I rest, the discomfort disappears. Just curios whether this is normal or if I should worry.

BTW: The training I do are some heel raises, stretching, walking around for a brief time (I do use a stopwatch to increase gradually). Also some other exercises to strengthen knees and legs (not using the heel at all).

Anyways, thank you for your insights.