Trainer's Strategy
For strong, beautiful, symmetrical legs, work out your lower body with three different exercise techniques that build muscle and strength.

Why it Works
Whether you want to look more toned, run faster or just feel steadier on your feet, this workout can help you get the job done, says certified trainer Philip Dozois, who designed it. Each move has a distinct goal - strength, power or stabilization. By using different training modes in one workout, you can challenge your leg muscles in new ways, which is key to quick results, Dozois says. You can also prepare for your favorite summer activities, from hiking to waterskiing. "Most people only train their legs for strength," Dozois says. "But you also need power and stabilization to deal with whatever life throws your way."

Muscle Mechanics
The quadriceps group consists of four muscles. The rectus femoris works as a hip flexor and a knee extensor. It crosses your knee and hip joints, attaching on your pelvis and below your kneecap. The three vasti muscles - the lateralis, medi and intermedius - run from the top of your thighbone to below your knee and work to extend your knee. With multimuscle exercises like the runner's lunge and power step-up, your hip flexors, buttocks , hamstrings and calves are called into action too. Your upper-hip and inner-thigh muscles also help stabilize your hips and knees during each movement.

Details
Do these moves as part of a total-body strength program. You'll need an 8- to 10-inch step, a leg-extension machine and a 2- to 4-pound medicine ball. Before each workout, warm up with 5 minutes of low-intensity cardio. End by stretching your quadriceps muscles, holding each stretch for at least 30 seconds without bouncing.

SHAPE Reader Model
Julie Bromley, 25, does an hour-long cardio or weighttraining program 4-5 times a week. "I'll be adding these moves to my workout," Bromley says. "They challenged muscles that I didn't realize I wasn't strengthening."

MUSCLES WORKED These exercises primarily target your quadriceps muscles: 1. rectus femoris 2. vastus lateralis 3. vastus medialis 4. vastus intermedius

What Works What's Philip Dozois' No.1 secret for superdefined legs? Besides using various training modes: Stretch. "Stretching can help you get stronger. You'll improve your range of motion, and stretching may enhance recovery," explains Dozois, co-owner of Breakthru Fitness in Pasadena, Calif. "It increases blood flow to your muscles, delivering fresh nutrients and flushing out waste products." For maximum muscle tone, he recommends doing quad stretches between sets as well as after your workout. "The quadriceps tend to get tight, especially if you spend a lot of time sitting during the day," Dozois adds. "If you don't stretch them, you'll be setting yourself up for possible knee problems and muscle imbalance."

1. Runner's Lunge

Strengthens quadriceps as primary emphasis; also works buttocks, hamstrings and calves; upper-hip and inner-thigh muscles work as stabilizers.

• Standing with feet hip-width apart, step back with your right foot into a lunge, left knee bent at a 90-degree angle in line with ankle and right knee bent, right heel lifted.
• Bend arms at 90 degrees in opposition to your legs, so right arm pumps forward and left arm pumps back as if you're running.
• Pushing off the ball of right foot, straighten left knee as you lift right knee up to hip height; simultaneously pump arms in opposition to legs, keeping abs contracted.
• Be sure to keep your left knee in line with your left ankle, toes pointing forward, hips square and torso centered.
• Hold for 2 seconds, then step back with right foot into another lunge.
• Do 1 set of reps with right leg, then switch legs and repeat.

2. Leg Extension

Strengthens quadriceps

• Adjust a leg-extension machine so the front pad is in line with ankles when lower legs are hanging at 90 degrees and knees are aligned with machine's pivot point.
• Sit on machine with hips and back against the seat, chest, shoulders and toes lifted; hold side handles for support.
• Keep abs contracted as you extend legs up in an arc until legs are straight but not locked; be sure kneecaps are facing up and feet remain stationary.
• Pause, then slowly lower to starting position; repeat for all reps.

3. Power Step-up

Strengthens quadriceps; also works buttocks, hamstrings and calves; outer-hip and inner-thigh muscles work as stabilizers. * Stand about 4-6 inches away from and facing an 8- to 1 0-inch step.

• Hold a medicine ball at chest level with both hands, elbows bent.
• Place left foot on step so you're in a split stance, right knee slightly bent, right heel lifted.
• Keeping abs contracted, bend both knees and jump straight up, simultaneously pressing medicine ball overhead. * Switch legs in midjump so you land with right foot on step and left foot on the floor, heel lifted, simultaneously lowering ball to chest height. * Be sure to keep toes pointing forward, Mips square and torso centered. ),-'Continue to alternate legs for all reps.

Trainer's Tips
Really focus on squeezing your thigh muscles, keeping them contracted throughout the entire range of motion for both the runner's lunge and the leg extension.

• As you do each rep, be sure to move through the full range of motion.
• Don't let your knees rotate inward or outward.
• Use your abs to help support and stabilize you.
• For balance, keep your eyes focused on a spot directly ahead of you; avoid looking down at the floor.

Basic Program	Exercise	Runner's Lunge	Leg Extension	Power Step-up
	Sets	2-3	10 with each leg	none
	Reps	2-3	10-15	30-40 pounds
	Weight Range	1	8-10 with each leg	2-4 pound medicine ball
Advanced Program	Exercise	Runner's Lunge	Leg Extension	Power Step-up
	Sets	2-3	10-15	30-40 pounds
	Reps	2-3	10 with each leg	None
	Weight Range	1-2	8-10 with each leg	2-4 pound medicine ball
	Special Instructions	Superset with runner's lunge.	Superset with leg extension.	None