I learnt that there is a no-man's land in table tennis: the center of the baseline. It seems it is most prone to the "elbow attack" which confuses you whether to hit forehand or backhand. So the right thing to do in TT is to always be on side to the other, and moving to the other side as necessary with two giant steps only.
Since I had to pick up the balls manually rather than the tennis racket-leg trick, I was bending down very frequently and that gave me a lot of dizziness due to my progressive lenses.
I find TT more physically demanding than tennis.