1. Find a sturdy doorway that has a flat, wide doorframe.

2. Stand facing the doorway and hold onto the sides of the doorframe at chest height.

3. Lean back as far as you safely can while holding yourself stable, keeping your body in one straight line and your heels planted on the ground.

4. Engage your back muscles to pull your body back towards the doorframe, squeezing your shoulder blades and lats together.

5. Pause briefly at the top of the movement and then slowly lower yourself back to the starting position.

1. Lie face down on a mat or a flat surface with your arms and legs extended straight out.

2. Engage your core and lower back muscles and lift your arms, legs, and chest off the ground simultaneously.

3. Hold the position for a few seconds and then slowly lower back down to the starting position.

4. Repeat for the desired number of reps.

1. Stand in a doorway with your feet hip-width apart and your arms extended straight out in front of you, gripping the doorframe on either side.

2. Engage your core and glutes to maintain good posture and stability.

3. Slowly pull your body towards the doorframe, bending your elbows and keeping your upper arms close to your sides.

4. Pause briefly at the top of the movement, squeezing your biceps.

5. Slowly lower your body back down to the starting position.

1. Grab a towel or t-shirt, hold it in both hands, and stand in either squat position or upright with feet hip-width apart.

2. Hold the towel overhead with your arms extended, and pull on both sides of the t-shirt or towel as hard as you can, as if you were trying to rip it.

3. As you continue to try to rip the towel or t-shirt, slowly bring your elbows out and back behind your body, squeezing your shoulder blades together.

4. When your hands get as close to your chest as possible, slowly return to the starting position and repeat until the set is complete.

1. Position yourself face-down on the floor with arms stretched out in front of you, palms facing the floor, legs closed.

2. Slowly lift your chest, arms, and legs slightly off of the ground.

3. Slowly so as to feel the tension and resistance, move your arms down toward the hips and legs outward, and then return to the original position, as though you’re performing jumping jacks or a snow angel.

4. Rest limbs on the ground briefly before beginning the next rep.

1. Start in a plank position with your hands directly under your shoulders and your body in a straight line.

2. Engage your core and bring your right knee towards your chest, then quickly switch and bring your left knee towards your chest while simultaneously extending your right leg back.

3. Continue alternating legs at a quick pace, as if you’re running in place.

4. Aim for a quick pace and keep your core engaged throughout the exercise.