Drop and give me 20! Yep, I am talking about push-ups and want you to consider adding them into your daily life. Why? Because you can do them anywhere and not only do the work your arms, shoulders, and chest, they also work you abs. And because they require no equipment, you can do push-up anytime, anywhere.

As long as you are not pushing your muscles past failure and practice good form [1], you won't hurt yourself. To build endurance, it's best to perform multiple sets throughout the day and try different variations, too — we don't want you or your muscles getting bored. I just do a few shoulder circles and scarecrows [2] to warm up my shoulders and chest, then I drop to the floor and do a set of push-ups. I manage to get two to three sets of 10 to 15 push-ups easily throughout my day, do them when:

• Waiting for the coffee to brew — I love my Chemex but it can feel like forever while water boils and the coffee brews.
• Anytime I am on hold, which isn't all that often since I do most business online rather than the phone.
• Watching TV, especially when somebody else is fast forwarding through the commercials.
• Folding laundry, because push-ups are more fun than folding laundry — am I right?
• When I let my dog out; she always wants back in 60 seconds later, definitely enough time to do a set a push-ups.
• Before bed, after I change out of my clothes and into PJs.

Even if you feel a standard push-up is beyond your current upper-body strength [3], adding them into your day either on your knees or on doing incline push-up on a chair, park bench, or kitchen counter, will build up strength in no time. Plus you will have some seriously toned arms, too.

Here are some push-up variations for you to fit into your day.

Knee Push-Up

• Begin in plank with your knees on the mat.
• Exhale to bend the elbows, lowering into a push-up. Inhale to straighten your arms. This completes one rep.

Elevated Push-Up

• Start in plank position [4], placing your palms on a stable surface like a wall, chair, kitchen counter, back of couch, or bench. Keep your arms and legs straight with weight on your toes, shoulders above the wrists, and core engaged.
• Take a breath in, and as you exhale, bend your elbows out to the sides and lower your torso in one piece (it's common to leave your pelvis behind, aka sticking your butt out) toward your hands. Stop when your shoulders are in line with your elbows. Inhale and straighten your arms to return to your starting position. This counts as one rep.

Basic Push-Up

• Start in a plank position with your arms and legs straight, shoulders above your wrists.
• Take a breath in, and as you exhale, bend your elbows out to the sides and lower your chest toward the ground. Stop as soon as your shoulders are in line with your elbows. Inhale to straighten the arms. This counts as one rep.
• If this is too difficult, do this exercise with your knees on the floor.

One-Legged Push-Up

• Start on your hands and knees.
• Extend your left leg behind you so it's parallel with the floor. Engage your abs.
• With your leg extended, bend your elbows, lowering your torso toward the floor while keeping your left heel in line with your left hip.
• Straighten your elbows to push yourself away from the floor, completing one rep.

Chaturanga Push-Up

• Start in a plank position with your arms and legs straight, shoulders above the wrists.
• Keeping your upper arms parallel, bend your elbows, lowering your chest until your shoulders are in line with your elbows. The elbows should touch your ribcage.
• Inhale to straighten the arms. This counts as one rep.

Down Dog Push-Up

• Begin in a Downward Dog but on your elbows [5] instead of your hands. Exhale, and press hands into the mat to straighten your elbows. Pull your navel up toward your spine to move the pelvis up and back, coming into a Down Dog [6].
• Inhale and lower your elbows gently back to the mat to complete one rep.

Diamond Push-Up

• Begin in plank position. Place your hands together, directly under your sternum, with the tips of your index fingers and thumbs touching. Your fingers and thumbs should form a diamond or triangle shape.
• After an inhale, exhale to bend your elbows, lowering your chest toward the floor.
• Inhale to straighten the arms.
• This counts as one rep.
• If this is too difficult, try separating your hands a couple inches or widening your feet slightly. Still too hard? Then lower the knees to the ground.

T Push-Up

• Begin in plank position.
• Bend your elbows lowering into a push-up.
• Straighten your arms and lift your right arm toward the ceiling, twisting into a side plank to make a T shape with your body.
• Rotate back to plank, placing your right palm on the floor to lower into a push-up.
• This time as you straighten your arms, rotate to the left lifting the left arm up. Return to plank to complete one rep.

Asymmetrical Push-Up

• Begin in a plank, then lower your left elbow to the ground, with your forearm crossing under your chest. From this position, bend your right elbow, lowering your body to the mat. Use your abs to keep your torso in one piece as you come to the floor.
• Exhale as you straighten your right elbow to return to the starting position. This completes one rep.

Spider-Man Push-Up

• Start in a traditional plank position, with your hands under your shoulders and your body in one straight line.
• Bend your elbows out to the side to lower your torso toward the floor, and bring your left knee forward to touch it to your left elbow.
• As you straighten your arms, return to plank position, bringing your left foot next to your right; then repeat this move on the other side. This counts as one rep.

Push-Up With Alternating Lunges

• Begin in plank position.
• Do one push-up, bending and straightening the elbows.
• With straight arms, step your left foot forward to the outside of your left hand. Look up and press your pelvis slightly forward to increase the stretch in your right hip flexor. Step your left foot back and do another push-up.
• Step your right foot forward to the outside of your right hand to stretch your left hip. This completes one rep.

Plyo Push-Up Prep

• Start in a plank on your knees. Move your left hand out to the side, then bend both elbows lowering your torso toward the mat. Straighten your arms to return to plank. This completes one rep.
• Switch your hands, bringing in the left hand while stepping the right hand wide — this is where you should try jump off your hands. Perform a push-up. This completes one rep.