By Therese Iknoian

If all the confusing information you sort through about exercise -- how hard, how much, how often -- isn't bad enough, consider the insider lingo you also have to get the hang of.

There you are, dressed in all the right duds at the health club, on the trail or in a court, and suddenly someone starts talking about lats, hams and quads. Excuse me, who? Those imbedded in the physical culture kind of assume everyone knows these nicknames. Don't be embarrassed, though, because even some exercise enthusiasts don't. Call this a primer for everyone who's been afraid to ask:

Quads -- proper name: Quadriceps Femoris -- This is the thick muscle group in the front of the upper leg. It's called "quad"-riceps because the group has four muscles, but we won't complicate matters with their long Latin names. Quads to you.

Abs -- proper name: Rectus Abdominis -- This sheath of muscles on your front side holds in your organs and, because it is divided into strips by tendons, imparts the bodybuilder's ripples. Toning the "abs" actually means working on four muscles that run in different directions. But "abs" is fine.

Lats -- proper name: Latissimus Dorsi -- Look for a large V-shaped muscle in your back that connects your shoulders, arms and spine. If you envy the V-shaped torso of muscle-bound types, it's the lat muscle you're eyeing. The V-shape comes from its width at your shoulders and narrowness where it connects to your low back.

Pecs -- proper name: Pectoralis Major -- a triangular clump in your upper chest that links shoulder bones, mid-chest and arm. Well-sculpted pecs in your chest make you look as if you can kick sand in someone's face. Hint: A man can cross his arms tightly under his arms and, by pushing outward on his pecs, can make his chest look bigger. You'll see this strutting pose in the gym. Toned pecs can also help women ... for obvious reasons.

Traps -- proper name: Trapezius -- Often, it's the trap muscle that knots up in your neck from stress. This huge muscle that's responsible for all kinds of movements runs from the base of the rear of your head, down your spine and out to the upper tip of your shoulder. Big traps give football players that no- neck look because the part on the top of the shoulder thickens with exercise.

Glutes -- proper names: Gluteus maximus, gluteus medius, gluteus minimus -- Otherwise known as the buttocks or derriere. Gluteus maximus is (pure logic here) the largest part and what we usually refer to because it plays the greatest role in locomotion and rounding out your pants. Medius is a medium-sized glute more responsible for stabilization and posture. Minimus is, yes, the smallest piece buried deep under the others.

Hams -- This term is a nickname for a nickname. "Hams" stands for hamstrings, a common term for the group of three muscles (biceps femoris, semimembranosus and semitendinosus...got that?) that runs from the bottom of your pelvic girdle down the back of your leg to your knee. Bending your knee to move your ankle toward your glutes contracts the hams. Clear?

Oh, there's more, such as "delts" (shoulders), "tris" (back of upper arm or triceps) and "bis" (front of upper arm or biceps). Toss a few of these words into your vocabulary and you'll sound like a pro before your abs have ripples.

© 1999 Therese Iknoian. All Rights Reserved.