Some great comments here

.
I'm turning 40 this year and I've been focusing a lot on diet and exercise (dropped 8 kilo since last October

).
I do a mix of cardio (spin classes) and strength training (upper body, mostly free weights). I'm lucky to get on the water twice a week, so the training is essential...it gives me more stamina and the skills stay intact longer when you're not tired (sailed over two hours yesterday in 30K+ without any cramping or soreness).
The other benefit I notice from the strength training is my forearms are a lot stronger and my grip strength is better.
Haven't done much yoga, but my missus is training to be a yoga instructor, so I should take advantage of that too!
Ps: I reckon that eating pies for speedsailing is a crock! Being heavier just means you need to use a higher volume board = more width = slower/scarier in chop. Fat is just excess baggage that screws up your power-weight ratio.