weight on? holy crap! best thing. start running or join a Gym. fitness is more what you need. mental toughness as well.
The IT field they offer (OCSS i think) trains you for field networks and cisco CCNA. and they keep training you as well.
from what i have found is that most traineeships are advertised internally.
though of joining the defence force, the army has a pretty good IT field to go into if you can put up with the bullshit