In reply to Antigua:
This isn't a proven system by any stretch, but last summer, prior to a knee injury, I worked on the basis that a half-ironman-a-week was probably a manageable goal. All the weekday stuff was done at lunchtime so it impacted as little as possible on work and family life. My regime was something like this:
Monday: swim 1km
Tuesday: Run 5km, fast
Wed: Climb 3 hours
Thurs: Run 5km, fast pace
Fri: swim: 1 km, working on refinement, drills, etc
Sat: Run: 15km, steady
Sun: Long bike ride - 90 - 130km, steady pace
Plus a cheeky mid-week evening ride if I could squeeze it in.
