Having a strong core is not only important for looking good in a swimsuit; it also helps with balance, stability, and preventing injuries.

Although many people think that you need equipment or a gym membership to work on your core muscles, there are actually plenty of exercises that you can do at home with no equipment needed. Here are five exercises for a stronger core that you can try at home.

1. Plank

The plank is a classic exercise for strengthening your core muscles. To do a plank, start on the ground on your hands and knees. Extend your legs straight behind you and come up onto your toes.

Your body should be in a straight line from your head to your heels. Engage your core muscles and hold the position for as long as you can, aiming for at least 30 seconds.

2. Bicycle Crunch

The bicycle crunch is a great exercise for targeting your obliques as well as your rectus abdominis (your “six-pack” muscles). To do a bicycle crunch, lie on your back with your hands behind your head, elbows out to the sides.

Lift your legs and bend your knees to bring them to a 90-degree angle. Lift your head, shoulders, and upper back off the ground. Start to pedal your legs as if you were riding a bicycle, touching your elbow to the opposite knee with each rep.

3. Bird Dog

The bird dog exercise is a good one for targeting your lower back muscles as well as your core. To do a bird dog, start on your hands and knees.

Engage your core muscles and extend your right arm straight out in front of you while lifting your left leg straight behind you. Hold the position for a few seconds before returning to the starting position. Repeat on the other side.

4. Mountain Climber

The mountain climber exercise is a good one for getting your heart rate up while also working your core muscles. To do a mountain climber, start in a plank position. Bring your right knee in towards your chest, then return it to the starting position.

Repeat with your left knee. Alternate between the two knees as quickly as you can while maintaining good form.

5. Bridge

The bridge exercise is a good one for working your glutes (butt muscles) as well as your lower back and core muscles. To do a bridge, lie on your back with your knees bent and your feet flat on the floor.

Lift your hips up towards the ceiling, squeezing your glutes and engaging your core muscles. Hold the position for a few seconds before lowering back down.

Try incorporating these five exercises into your routine to work on building a stronger core. Aim to do each exercise for 30 seconds to start, and gradually build up to longer sets and more repetitions as you get stronger.