January and February is the time for base miles.
Myself, I think cycling—of the three disciplines we do—is the most important for the aerobic base achieved during this time for a couple of reasons.
It is hard to get hurt cycling if you are doing it technically correctly, and so long as you aren't crashing. Cycling is curative. It is non-ballistic, and is not the ache-producing, joint-pounding, muscle-knotting, imbalance-producing activity that running often can be.
When you are on the bike you are building an endurance and muscular base that will aid you in all three endurance disciplines in which you are engaged.
Also, physiologically, there is no other way to spend four or five hours exercising. You can't do that running or swimming. So you'll build an endurance base, which is useful for both of the other two disciplines, without damaging yourself.
But you have to make sure you are taking care of yourself properly in these early weeks and months. The most important thing is to be properly positioned on your bike. You'll also want to take care to keep your cadence up to somewhere between 80 bpm on the very low end to a high of 95 bpm.
Pile in the miles. Go for it. Do a President's Day ride. Get a couple of your buddies and go for three days over that weekend, 80 or 100 miles each day. You'll want to do these three- or four-day bike jaunts once every couple of months, by the way, and one way to get this into your schedule is to take your vacation days one at a time, like a Friday every other month or so.
It is nigh unto impossible to do an Ironman (which is probably what you want to do, right?) without some really big weeks on the bike. It is impossible to contemplate a 350- or 400-mile bike week if you think of it overlaid on your regular work week. But 300 miles over a three-day-weekend makes a 400-mile week within reach. And this is how you should be spending your pre-season, doing weeks just like this, at a very low level of effort.
I don't believe in doing the same sort of schedule week-in and week-out. I prefer to gang up miles in one event during a week, and a lot of pro athletes approach their training this way. Once a month is enough for your big bike week. Perhaps 200 miles, perhaps double that; and if you're a top-level male Ironman pro, perhaps almost triple that.
But on that week the running will be almost nil, as will the swimming. On your big run week—and big depends on what sort of runner you are; a top pro who's been doing it for a while might do 80 miles, another might do 50—you will not ride much at all, but you'll perhaps swim quite a bit, since running just doesn't take that long. And, of course, swimming can be another of those therapeutic and healing activities, somewhat ameliorating the damage you do during your runs.
You are possibly on a master's swim team, and that's a good thing. But master's swimmers only swim. That is the beginning and the end of their glory. They aren't going out for a bike or a run afterward. They're quite happy to take you out of your target heart rate. It is impossible to do the "main set" and also keep your pulse below 70 percent of your max.
So realize that during these early winter months you'll have to cool your jets in the pool. Go to the back of the line. Go down a lane. Do lap-swim if you have to. But resist the urge to duke it out. Well, OK, you can duke it out once a week, maybe. But on the other days just do the laps.
Here's something else to keep in mind:
I was talking to Tim DeBoom just two weeks before his third-place finish in Hawaii in '99. He said something that is so very true, it showed insight, and it is to his credit that he realized it. The previous years, as he was getting better and finishing higher, were not spent training for Hawaii, he said. They were spent training to be able, finally, to be able to train for Hawaii.
It is hard to do the training required to do an Ironman. You can't do Ironman training your first year. You can train to finish it. But you can't train to do your best Ironman until, perhaps, your fifth year.
It takes a lot of base miles in the early season, many seasons in a row. You're starting now. Doing it right means doing it one step at a time. Today's step is long slow base miles.