IT'S 7:55 ON A SUNDAY MORNING, and I am knee-deep in a frigid lake with 100 other certifiables wearing Speedos, swimcaps and serious goose bumps.

I spit into my goggles -- I hear this keeps them from fogging -- and tally the cash I've spent in preparation for this, the 2003 Lake Chatuge Sprint Triathlon: $450 for a used bike, $60 for a dorky helmet, $70 for swim shorts and a bra-top that squeeze in all the wrong places, $15 on carbo snacks called "Gu."

MINI-ME MARATHON: This is a "sprint" triathlon, sort of the Ironman's Mini-me: typically, a half-mile swim, an 18-mile bike ride and a 3.1-mile run.

My friends and I decided to try a sprint because we were turning 30 and wanted to leave our 20s in better shape than we'd entered them.

I'm a longtime jogger and a lacrosse player, so training for the run came easy. But I wiped out several times on my bike, and a lifeguard laughed at my first attempt to swim a lap. All of this runs through my head as I shiver at the edge of this north Georgia lake, when, without so much as a "ready, set," the marshal yells "Go!"

"AM I GOING TO DIE?" We all dive headlong into the murky water. Bodies are all around me, thrashing, kicking water into my face. My eyes, used to the soft blue of the indoor pool, now see nothing but brownish-green when I open them underwater. The cold stiffens my muscles and shrinks my lungs. I start flailing about, my training shot to hell. Nearly in tears, I start to wonder, "Am I going to die?"

Apparently, I'm not alone; a motorboat swings around and picks up two men in distress.

When I finally stumble out of the water, a small cheering section greets me. Someone tells me I've finished the swim in the upper half of the group. Can that be?

I climb onto my beat-up bike and hit the road. I'm alone for most of the hilly ride. So I talk to myself, hum "Eye of the Tiger" and occasionally grunt an obscenity. My thigh muscles burn.

WHAT THE?! The bike route is a loop, so as I near the halfway mark I see the sinewy, sleek superstars cruising down the hill I'm now struggling with. Oh, how I hate them.

After 54 minutes, I ditch my bike at the racks. I'm ready to run, but my legs aren't. They're heavy as lead. After about a mile -- uphill, again -- my legs wake up and I pick up my pace. Then a cramp creeps into my ribs. Now this? I try to ignore it.

As I head into the last stretch, I see my supporters. They're yelling and waving -- so supportive!

Suddenly I realize they're frantically trying to tell me to turn. I'm about to miss the narrow chute that is the finish line. I quickly cut to the right and knock into a short, shirtless triathlete. He scowls at me. Whatever, dude. After 1 hour and 44 minutes, I'm done.

When's the next one?

TIPS FOR FIRST-TIMERS

Be prepared to spend some cash. Want a brand-new road bike? That could set you back $3,500. Cycling shoes that clip into the pedals? $180. A wetsuit? $400. Consider buying a used bike, wearing running shoes and dusting off that Speedo.

Start training now. Experts recommend couch potatoes start training seven months ahead. If you're in good shape and comfortable with at least one of the events, four months may be enough. You can find the right training program at www.beginnertriathlete.com.

Your legs may feel like lead when you start the running portion. This is normal. It has to do with lactic-acid build-up in your legs. It should go away after the first mile or so.

TRY SOMETHING DIFFERENT

An occasional feature: Let us know about your adventure in trying something different -- from finally taking salsa lessons to learning French to skydiving . . . the possibilities are endless. Send us an e-mail at access@ajc.com.