Night fever, night fever...

I'm on nights at the moment and feel like I'm in a perpetual state of jet lag.
The work hours are 4pm to midnight (which is rapidly overspilling into 1am as the Socceroos beat the Euro Champs Greece, NSW took the first Origin game, Aussie troop have dropped into East Timor for an urgent peacekeeping mission... the list goes on).
I'm making things ten times worse for myself by INSISTING that Bo and I get up for the gym at 5.15am. Atleast four weekdays a week.

This may seem over-ambitious, but since she's at TAFE three nights a week and I'm on nights until I go to the UK (which is when my next day off is), its the only conceivable way we can get to the gym together (for support, inspiration, pulling muscle-Mary faces at eachother).
But I am BUGGERED.

I'm wide awake and starving when I get back, but by 9am I'm asleep and my day is totally ruined. Hmmmmmmmm.
Not sure what the solution is - answers on a postcard please.