Strength Train at Home—No Equipment Required

Easier Form: Keep your knees bent at a 90-degree angle so you get more support from your legs.

Squats. Stand with your feet hip distance apart and bend your knees, sticking out your rear end as if you’re about to sit down in a chair. Make sure your weight shifts backwards as you squat, ensuring that your knees don’t go past the front edges of your toes, until your knees are at a 90-degree angle (thighs parallel to the floor). Then press into your heels to push yourself back to a standing position. Do three sets of 10 regularly and find some jeans that show off your backside.

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Easier Form: Lessen the angles if the move is too intense—try a 60-degree bend in the knee to start.

Lunges. Think about taking a big step forward. Bend your front knee to a 90-degree angle, making sure that your knee tracks in line with your second-biggest toe and doesn’t go past the front edges of your toes. Your back knee should also bend until it hovers a few inches above the ground. Make sure your back and head stay straight up and down—do not lean forward from the hip. Do three sets of 16 (eight for each leg) and get ready to break out the short shorts.

Easier Form: Hold onto a chair at your side to help support proper form during a lunge, or try a half-lunge, where your back knee only bends slightly. (Be sure to still keep your back straight!)

Crunches and Core. Crunches are the anytime, anywhere staple. Lie down on the floor with bent knees, hands behind head, belly button pulled in toward your spine and lower back against the floor. Slowly contract your abs, exhaling as you bring your shoulder blades just two inches off the floor (lower back stays on the ground). Hold at the top of the movement for a beat, then inhale as you relax down, but don’t relax all the way—pull up into the next move before your head hits the ground. Do three sets of 12 with this in mind: Bare midriffs are back in style.

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Easier Form: If you’re somewhere where you can’t splay out on the ground (like, uh, your office), you can still do core work. Sit in your chair with your back straight and your hands behind your head. Bring your left knee in to your chest, curving your spine so that your right elbow touches the knee across your body. Alternate knees and elbows for three sets of 12.