Since I have given advice to a few newbie triathletes, I thought it might be worth compiling some of those ideas here. I'm not sure how many of you have ever considered (or would ever consider) doing a race like this, but it is a lot of fun and a great challenge if you're ready for it. Remember that my advice is the advice of a non-expert amateur, so your mileage may vary.
Can I do a triathlon?
Well, first, a more important question: Do you want to do one? Don't do it because you think all the cool kids are doing it, do it because you are really excited at the prospect of doing a multisport race.
Also remember that there are triathlons and there are triathlons. I have done multiple sprint triathlons and two international distance (Olympic) tris. Wikipedia has a nice table listing standard race distances. A sprint takes me around an hour and a half to complete and I feel tired and happy afterward. An international/Oly takes me about three and a half hours, and both times I tried it, I got so hot and tired that I finished feeling like I might not make it at all. At the second one, in Chicago, I sat down on a curb and cried when I finished. I can't even contemplate doing an Ironman, not even just to finish it. "Just finishing" something that takes 14-17 hours to do is not something I think I would enjoy.
I would recommend that all beginners start with a sprint or even a super-sprint race. I think that most people of moderate-to average fitness could do a triathlon of these distances as long as they took the time to prepare properly. I had 9 months to train for my first sprint, but I don't think most of the other first-timers had trained that long, but I hadn't even swum serious laps in the pool before I decided to do a triathlon, so I had lots of work to do. I'm assuming you're reading this in the fall and thinking about a race next summer, so you'd have a nice long time to get ready for your first race.
How do I get started?
For a sprint triathlon, you'll need to be able to swim half a mile, bike 10-12 miles, and run 3.1 miles. If you can already do that, great! You can sign up for a race tomorrow. Otherwise, start working your way up to those distances. I generally work out at least five days a week, and do at least one swim, one bike, and two run workouts each week. The extra workouts depend on my particular focus at the time. You might also consider adding strength training, yoga, and/or Pilates to your workouts to keep you strong and limber. There is a lot of more specific advice online, but for brand-new beginners, the important thing is to get started as soon as possible. I liked sites like trinewbies for answering all the "dumb" questions I had, like what to wear (I wore something like this, with a sports bra underneath, but you want to wait until closer to your race date to buy any fancy trisuit, because you're might be thinner by then). I also think that books like Triathlon 101 and Slow Fat Triathlete can be really helpful and motivating.
What do I need to get started?
A lot of people seem to get all excited about the gear. You could spend endless amounts of money on triathlon swag, but I don't recommend going out and buying thousands of dollars worth of stuff before you start training. This is a list of the bare minimum stuff you need to start training for each event:
Swim: Swimsuit, latex swim cap, and goggles. Membership to a pool where you can swim laps. You don't need a wetsuit to get started or to do a sprint race (or maybe ever: I bought one and hated it and sold it on ebay). Once summer comes along, try to hook up with a group that does open water swimming. You don't want the first time you swim in a lake to be the day of the tri.
Bike: Basic gym clothes (including a good sports bra if you're a woman) and membership to a gym with Spinning classes. I don't recommend going out and buying a new bike right away, because you'll probably get talked into buying a hybrid bike, which you really don't want. You want a road bike. If you go into a store without some confidence about what you need, chances are, that guy at Play It Again Sports! who doesn't know a triathlon from his elbow will convince you that a hybrid or a mountain bike is great for triathlons. It's not. It really isn't. It's fine for training for a triathlon, but on race day, you want a road bike if you don't want to get passed by every other person on the course. Trust me. Because road bikes are expensive, I recommend taking Spinning classes or training on whatever bike you have lying around until a few months before the race, and then buying a reasonable road bike or borrowing one from someone who will let you use it for a few months to get used to it.
Run: Weather-appropriate clothes and/or a membership to a gym with a treadmill. A sportsbra if you're a woman. I like to run outside in all weather, so I have a lot of fancy running clothes that keep me cool and dry in the summer and warm and dry in the winter. Cotton is crummy for running because as soon as you start running, you will start to sweat, and cotton just soaks up the sweat and weighs you down. Target actually sells some nice warm-weather running gear, but the cold-weather jackets and pants can get expensive. If you're trying to go bare-bones, it might be better to train indoors on the treadmill where it's temperature-controlled and you can get away with wearing an old cotton t-shirt and yoga pants. I do recommend Wright socks, though, and think even a bare-bones triathlete should have some. They keep the blisters at bay. You also need running shoes. There are all kinds of opinions and advice on shoes, but my advice is to start with a fairly basic shoe and move up if you need to. I have had more trouble with the $120 running shoes than I have with the $70 models. I like Asics or New Balance, but it really depends on your foot and your stride. You can try the various shoe guides online or go to a running store and see if they can give you some good advice.
Other stuff: If you have a good digital watch or a heart-rate monitor with a watch, you can run without a measured course and just base your workouts on elapsed time. I think it would be hard to train without one. You can get fancier with a GPS and all that junk, but we're talking bare-bones here. You also want some kind of notebook or log to record your workout, or you can use a cool site called athlinks, which has a workout journal and helps you keep track of your results.
This is all you really need to get going. There is plenty of advice out there on how you can spend more money and get more obsessive about your training plans, but for me, the best advice is to just get out there and do it. You can fuss over the details on your second triathlon. This advice will get you going on training. In a later post I'll give you everything you need to have and know on race day, if people seem to be interested.