Ok I just did it again
Player was at 91,000 Market Value and Season wage was $2500.00 ( and this info was checked this morning)

I set him as a Normal Training session of stretching and it awarded me a skill point which I applied to him.

a
I refreshed page and his Market Value went to $92,000 (which I understand
but his Season salary went up to $3500 (thats the one I don't understand