Meet the Fitterati

Best Personal Trainer Blog: Fitnessista

Fitnessista.com

Gina Harney, 27, Tucson, Arizona

Gina, a military wife, a new mom, and a fitness instructor, constantly mixes things up in the gym. "I keep my body guessing so it won't kick into cruise control, and I do the same with my clients," she says.

Fat blaster: "Tabata intervals burn major calories. Sprint or jump rope as fast as you can for 20 seconds, then rest for 10. Repeat this eight times for a total of four minutes."