If anyone was wondering how to change the font sizes without messing around with the Matlab default fonts, and change every font in a figure, I found this thread where suggests this:
set(findall(fig, '-property', 'FontSize'), 'FontSize', 10, 'fontWeight', 'bold')
findall
is a pretty handy command and in the case above it really finds all the children who have a 'FontSize'
property: axes lables, axes titles, pushbuttons, etc.
Hope it helps.