Back to the training idea (sorry for the digression!) - here's the plan:
- Tuesday - Climb/Lift [15/2.5]. After teaching my Yoga class i'll do 15 minutes of laps at the climbing wall (only 22 feet high, but better than nothing!), using big holds for a bit to warm up then increasingly smaller ones. I'll be using an auto belay system so i can just climb up, let go and get lowered down and get 5 seconds rest. This should be pretty good for creating an interval like structure. I'll do or so of tabata style intervals for pushups for 2 and a half minutes.
- Wednesday - Bike or Run/Lift [20/5]. The biking/running will be done on a stationary bike or treadmill and probably use the hill program which essentially creates four one minute work intervals and four one minute rest intervals after a warm-up. I usually set the pace and level so that its a brutal workout. Each week i'll alternate running and biking and will aim to make each week's run/bike harder than the previous one by some metric (speed or level). I'll do 5 minutes of tabata inspired intervals for legs (both quads and hamstrings).
- Friday - Swim/Lift [15/2.5]. I'll swim, either doing a straight tempo swim or some sort of interval workouts. Often i'll do a 300 warm up, 8 x 25 as fast as possible, leaving every 30 seconds, then 300 or 350 warm down. I'll lift for back, tabata style - 20 seconds on, 10 seconds rest, for five minutes. Typically i'll do pulldowns or rows of some sort. Ouch.
- Sunday - Run or bike [45 or 75]. I'll alternate running and biking so that if i ran on wednesday i bike on sunday. Both of these efforts will be pretty serious. for a forty five minute run i might do a 2 mile WU @ 7:30 pace, then 1 mile @ 6 min, 1 mile @ 7 min, 1@ 6, then the rest @ 7:30 pace. For a 70 minute run on the treadmill i might do the random program on lvl 6 (0-5% incline), starting at a 7:30 pace (8mph) and increasing the speed by 0.1 mph every 7 minutes to finish at a 6:40 pace (9mph).
A month might look like - week 1: run wednesday, bike  on sunday. Week 2: Bike wed, run  on sunday. Week 3: run wed, bike  on sunday. Week 4: bike wed, run  on sunday.
One of my favorite workouts, and what i view as a critical piece of the plan, is the wednesday workout. I find that by setting a 'baseline' the first wednesday after returning to training (after a major effort - my reset button) and forcing myself to 'up' the intensity every week (which is why i use a treadmill/stationary bike), i can progressively rebuild my running and biking to a pretty high level over the period until my next reset. If i didn't have a reset - ie no big run or race that required serious recovery - i'd eventually start to plateau as i'd begin approaching the limit of fitness achievable on such limited volume.
Of course the limit of this fitness, at least in my opinion (and experience), is sufficiently great that it allows me to do pretty much anything.