Acceptable forms of cross-training + my month in review

Being a runner has always meant I have plenty of options for cross-training. Elliptical, ARC trainer, stationary bike, swimming, etc. (I've also been known to count things like going up and down the stairs really fast, ice skating, carrying around my 10-pound dog for half an hour, and vacuuming as cross-training). But it occurred to me the other day that there are not many options for cross-training for a triathlon. In addition to running a few times a week, biking and swimming are now obligatory activities. Trying to balance training for three different sports doesn't leave much room for other workouts, anyway. I suppose biking and swimming are low-impact enough that they don't require rest days, or cross-training days, like high-impact running does. Things like the elliptical and ARC trainer actually seem pointless while training for a triathlon, because they don't seem to have any specific benefits for swimming or cycling.

Of course, that didn't stop me from trying to think of cross-training activities that might help with cycling and swimming techniques. Here are a few I came up with:

1.) Filling up the bathtub with water, sticking my head in, and holding my breath for as long as possible, thereby increasing my lung capacity (WARNING: Don't try this at home)

2.) Laying on my back and moving my legs in a cycling motion for 30+ minutes

3.) Balancing on my stomach on an exercise ball, while practicing my freestyle stroke. This one has the added bonus of strengthening my core as I attempt to remain balanced.

I only came up with these three before I realized how futile it really was. OK fine, I realized how silly it was after just the first one, but I was determined to see if I could think of anything else. It just seems weird to be solely training, and not taking days to cross-train. I guess the only real cross-training I'll be doing for the next few months is strength-type stuff. Unless any of you know some good cross-training activities for triathlons that I'm just totally unaware of? 

And now, because it is February 1st, and because it seems to be the popular blog thing to do, I present to you my "month in review." Keep in mind that during January I was both tapering for, and recovering from, a marathon. That's my excuse and I'm stickin' to it!

January Stats
Running: 50 miles (yes, 26.2 of those were in one day)
Cycling: 90 minutes (on the indoor trainer)
Swimming: 700 meters
Strength training: 80 minutes

Quite pathetic, especially the cycling and swimming. But I was mainly focused on running because of the marathon. Hopefully my stats for February will look at least slightly better.