There are two approaches to cross-training: as a regular part of your training, or as a workout of last resort.
It can be incorporated into a complete training program (much like the OJ in a complete breakfast!) as an added benefit. Running every day is great, but it’s even better to bike or pool or lift or swim on occasion to strengthen muscles not directly related to running. Cross-training also gives you days off of the pounding of running without missing working out. Overall cardiovascular fitness and muscular stability is the goal.
Despite all of this, cross-training is the bane of my existence and I avoid it like the plague (sidenote: who doesn’t avoid the plague???)
I see cross-training as an act of desperation - the only time I really cross-train is when I can’t run. I see time on the bike or in the pool as a place-holder for running – something I don’t enjoy but do to maintain my fitness (and sanity) when I’m not out pounding the roads and trails. (Right now I'm trying to be smart and alternate running with cross-training days.)
But when I need to cross-train I will do it. And if I’m going to do it, I’m going to do it right. No leisurely bike-rides, no slow-motion pooling – I make it hurt because I may as well get as much out of my time in an icky place as possible!
If you’re used to running, you know what a solid run or workout feels like. You know that if you’re absolutely gasping for breath you’re probably working too hard, and that if you can carry on an easy conversation it’d better be a recovery day. But when you’re cross-training sometimes it’s harder to judge. Just how hard is too hard? What’s too easy? Obviously it depends on what you’re doing and what kind of day and week you’re having, but I have a few standards to determine if I’m getting a worthy workout.
In college I asked my coach how to know if I was doing enough on the stationary bike. His advice, though mildly horrifying, has stuck with me: It’s hard to get a good full-body workout on the bike, since it’s mostly your legs. So to know if you did enough, when you get off the bike you should be surrounded in a pool of sweat.
The pool is even trickier. You can’t tell how much you’re sweating, since you’re in water. So I judge it by how out of breath I am.
Pooling is my preferred cross-training because it’s the closest thing to running. So I try to get myself just as out of breath in the pool as I would be on a run. This can be hard to achieve, since it’s easy to feel like you’re doing a lot just by moving around in the water. But forward motion isn’t the goal and it isn’t enough – by the time I’m done with my hour in the pool I should be tired, and when I get out of the pool my legs should feel shaky.
Just like when I'm running regularly, I like to have a structured plan for my cross-training workouts: I alternate easy, long, and hard workout days to keep things interesting and reward myself for good workouts.
In conclusion, don’t waste your time with leisurely workouts! Don't fool yourself into believing that an hour slowly swishing through the water equates to an hour-long run. Make the most of your cross-training so that you can get back to running fast asap!