Start: Rest a barbell on your traps and stand with the instep of one foot on a bench or sturdy stool 2 ½ to 3 feet behind you.

Finish: Do a split squat, descending until the top of your front thigh is parallel to the floor. Pause, then push back up to the starting position.

Start: Rest a barbell across your traps.

Finish: Take your long lunge step directly to one side rather than to the front, keeping your toes pointed straight ahead. As with a standard lunge, descend as you step so your lunging thigh ends up parallel to the floor. Push yourself back up t the starting position.

Start: Use a light weight-perhaps one-third of what you'd work with on back squats-and go for speed and power Stay away from this one if you've had back problems. Set up for a back squat with the barbell resting on your traps. Then squat down quickly until your thighs are at a 45-degree angle with the floor.

Finish: Immediately change directions and push from your calves to straighten your body so explosively that your feet come off the floor a few inches. Land as softly as possible on your toes, then immediately descend back to the starting position as you shift your weight to your heels.

Start: Stand with a barbell resting across your traps, your feet about hip-width apart.

Finish: With your nondominant leg, take a large lunging stride backward so that only the ball of that foot touches the floor. Simultaneously sit back into the lunge until your back knees is just an inch or two off the floor while your front leg is bent 90 degrees thigh parallel to the floor and shin perpendicular. Push off from your front leg to return to the starting position.