Technique critical for workout

For sedentary or overweight folks, walking into a gym can feel like an exercise in terror.

The next time you find yourself feeling dazed in some testosterone-charged landscape of machines and muscleheads, remember: Beneath those bulging biceps and chiseled abs, they’re people who once stood in your stinky sweat socks. Some of them are doing stuff wrong, and they don’t even know it.

That’s why it’s nice to have a personal trainer or at least a few sessions with one who can help you avoid becoming both inept and clueless. You might still feel self-conscious, but at least you’ll have good form.

To help you avoid looking like a fool — even if you feel like one — I’ve put together a workout of exercise classics and their classic mistakes, a little do-this-not-that primer. Proper technique means you get the most out of every move you make.

Do this Pushup

•Works: Chest, core, arms

•How to: Starting on all fours, straighten your legs with toes on the floor. Arms should be just outside the shoulder line. Keep your body in a straight line from head to heels, abs engaged, as you bend your arms and slowly lower yourself to the floor. Slowly straighten your arms.

•How many: Repeat 10-15 times.

•Make it easier: Do the same movement on your knees instead of your toes.

•Make it harder: Lift one foot as you lower yourself

Don’t Do This:

•Lead with your tummy, allowing your back to arch.

Do This Crunch

•Works: Abs

•How to: Lie on your back with knees bent and feet flat on the floor in front of you. Your feet should be hip distance apart. Place your hands behind your head so your thumbs are tucked behind your ears. Hold elbows slightly out to the sides and keep chin pointing upward. Curl up and forward, lifting your head, neck and shoulder blades off the floor. Keep a fist’s distance between your chin and chest to be sure to target your abs and not strain your neck. Pause at the top of the movement and tighten your abdominals. Slowly lower your head, neck and shoulder blades as you inhale and return to starting position. Remember to keep knees bent and back straight throughout entire exercise.

•How many: Do 2 sets of 15 to 20 reps.

Don’t Do This:

•Pull your head forward with your hands, allowing your chin to drop to your chest.

Do This Chest Press

•Works: Chest, arms

•How to: Lie on your back on a bench, step or mat on the floor. Feet should be flat on the floor. Hold dumbbells or a bar in your hands, arms bent at a 90-degree angle and elbows level with shoulders. Slowly extend your arms straight up, pressing the weights above your chest. Slowly lower the weights to the start position.

•How many: Do 2 sets of 8-12 reps.

Don’t Do This:

•Allow your arms to drop below your shoulder level, or bounce the bar off your chest.

Do This Row

•Works: Back

•How to: Stand with feet hip distance apart, arms straight, a dumbbell in each hand. Bend your knees and tip forward from the hip, keeping your chest lifted and a natural arch in your lower back. Bend your arms and pull them straight back, keeping your arms close to your sides and your elbows pointing to the back of the room. Try to bring your shoulder blades closer together as you pull back. Return to start.

•How many: Do 2 sets of 8-12 reps.

Don’t Do This:

Allow your shoulders to round forward.