The next time you hop on your bike, go for a run, or just hit the circuit after a few AirFit sessions, you'll feel like a super hero. 

What's AirFit's power? Is it the rays of the yellow sun shining down on you as you drive to the Pleasanton training facility? Mysterious substances in the steam room? Nothing that mythical: instead, they've built a space-age training room, then sucked the oxygen from it, creating an atmosphere similar to that of a high-altitude location.

Which means that those of us who live and work out in low-lying San Francisco will  be gasping for breath like we're on Day One at the Biggest Loser ranch as we make our way through their 50-minute "Mile High Circuit," "Mile High Relay," "O2 Row," "O2 Cycle," and even their "Summit Yoga" classes.

If only Rocky had had access to AirFit when he was going up against Ivan Drago. He could have been living the good life in Pleasanton, instead of chasing chickens in the steppes!

If you want to get a taste of what AirFit will do for you, start with the Mile High Circuit class, which will take you through a fairly standard high intensity interval training course of body weight exercises, cycle sprints, rowing, and weights, all at oxygen levels of about around 15,000 feet above sea level, if the gauge in the room is accurate. 

It's unlikely you'll need a gauge to tell you that you're not on flat land anymore, however, as your body has plenty of gauges of its own. It's amazing how quickly your system can react to the lack of oxygen, and AirFit director Carlo Maravilla says that some students even have a "panic response" at their first class, and have to step outside to gulp down some sweet Pleasanton air before finishing their workout.

The Summit Yoga class was a different kind of challenge, as the standard yoga instructor line of "pay attention to your breath" took on real importance when it felt like there was little-to-no-breath to pay attention to. It's definitely a trip.

According to Maravilla, AirFit is the largest altitude training room in North America, at about 1000 feet. If you ask him nicely, he'll show you the Hypoxico Altitude Training System that makes the room mock the Rockies, a massive device that's housed in a room larger than many San Francisco apartments. 

And it's all worth it, if AirFit students like Margarita are to be believed. A triathelete in training with a fitness-model physique, Margarita mixes AirFit workouts with her time on the bike, road, and pool, and says she can "really feel a difference" after her hypoxic training.

"It makes everything else so much easier. I feel so strong!" she says. 

AirFit is located in The Quad, 5860 West Las Positas Boulevard in Pleasanton. Your introductory AirFit class will cost $20, and class packages are available.

GEAR:

• You're going to be hopping from bike, to the floor, then on the rowing machine in quick succecession, so close-fitting pants or shorts and top are ideal.
• No need to wear cycling shoes for the average workout, your usual training shoes will be fine.
• Some students say that, because of the "altitude," their in-class performance is improved with compression gear. It's not necessary, but wouldn't hurt to try.