Now, after decades devoted to an explosion of diverse fitness options, these low-tech, low (or no) cost, basic training tools are back. Calisthenics are the mainstay of ``boot camp workouts,'' one of the hottest classes at trendy fitness clubs. New books and videos feature military-style shape-up routines, and there's a boom in outdoor programmes led by drill sergeant-inspired instructors who bark their charges through basic training regimens.

Back To Basics : The reason? ``Anytime you stick to the basics, it's going to work and you'll get results,''says Stewart Smith, a former Navy SEAL who trained candidates for the elite group's Basic Underwater Demolition unit.

Calisthenics use your body weight to provide resistance to strengthen muscles, Smith notes. "So you don't need fancy equipment or lots of money to get in top physical condition."

Plus, calisthenics can also provide an aerobic workout. ``Try doing a series of exercises called a pyramid where you start by doing one pull-up, two push-ups and three crunches, then do two pulI-ups, four push-ups and six crunches and keep progressing until you're doing 10 pull-ups, 20 push-ups and 30 crunches, then work your way back down, he says. You'll get your heart up."

But calisthenics, only work if you do them regularly, which is one reason for the popularity of the ``drop and give me 20'' motivation offered by the new boot camp. ``We hold your hand and kick your butt at the same time,'' says Patrick "Sarge" Avon, owner of The Sergant's Program.

About 500 people--evenly divided between men and women,ranging in age from about 25 or 50--work out in the Sergeant's programme. Exercisers must first enlist in a three week Boot Camp that meets five mornings a week for 45 minutes per session and costs $ 345. At the end of the ``camp'' students take a military style fitness test, which about 65 per cent pass. Graduates can join the Sergeant's Maintenance Program, a five-morning a week, hour-long workout, for $ 80 to $ 95 a month. Those who fail can re-up for Boot to camp, but at the lower fee of the Maintenance Program.

-- www.betterhealth.com