Your Muscle Flex Plan

You don't need separate workouts to build strength, pump up muscle, and burn fat. All you need is a smart, adjustable circuit like this one from Mike Boyle, M.A., A.T.C., owner of Mike Boyle Strength and Conditioning, in Massachusetts. Select your goal, and for the squat and the row, use the heaviest weight you can lift for the required reps.

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Goal: Strength (helps you lift more weight)

Reps: 5

Circuits: 3

Rest between circuits: 60 seconds

Goal: Muscle building (sparks growth)

Reps: 8 to 12

Circuits: 3

Rest between circuits: 45 seconds

Goal: Fat loss (turbocharges cardio)

Reps: 8 to 12

Circuits: 4

Rest between circuits: None

Do 1 set of each exercise with no rest between sets.

1. Decline pushup

Assume a pushup position, but place your feet on a bench. Your body should form a straight line from your ankles to your head. Bend your elbows and lower your body until your chest nearly touches the floor. Pause, and push back up quickly.

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2. Bulgarian goblet split squat

Cup the end of a dumbbell with both hands, elbows pointed down. Stand upright with your back foot on a bench. Lower yourself as close to the floor as you can. Pause, and then push up. Do all reps. Switch legs. Repeat.

3. Dumbbell row

Holding a pair of dumbbells, bend at your hips and knees until your torso is almost parallel to the floor. Let the weights hang, your palms facing behind you. Bend your elbows and pull the weights to the sides of your torso. Pause, and lower them slowly. That's 1 repetition.

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4. Barbell rollout

Load a barbell. Kneel and grab the bar with an overhand, shoulder-width grip, shoulders above the bar. Roll the bar forward, extending your body. (Don't let your hips sag.) Use your abs to pull the bar back. That's 1 rep.