The best at-home lower ab workout - 4 exercises to strengthen your core, recommended by personal trainers

• Your "lower abs" aren't a muscle, but some exercises may be felt more in the lower half of the abs.
• Lower ab exercises for strengthening the core include Russian twists and modified planks.
• Core strength is important for posture, balance, and overall stability.

Your core is made up of 20 different muscles, so mixing up your abdominal exercises is important in targeting all of them, says Jessica Mazzucco, a certified fitness trainer and founder of The Glute Recruit. While your "lower abs" aren't technically their own muscle, there are some exercises you may feel more in the lower section of your abdominals.

Here are five lower abdominal exercises you can do at home. Some require equipment, like a resistance band, and others do not.

These exercises should be performed two to four times a week on non-consecutive days to give your muscles adequate rest, says Jennifer Jacobs, certified personal trainer and creator of The J Method.

1. Deadbug

How to do it:

1. Start lying flat on your back with your arms extended up toward the ceiling.
2. Bend your knees and lift your feet off the floor.
3. Engage your core and keep your lower back pressed into the floor.
4. Extend your right arm above your head and your left leg out parallel to the floor.
5. Hold for one to two seconds without letting your arm and leg touch the ground.
6. Bring your arm and leg back to the starting position and repeat on the other side.
7. Aim to maintain 20 to 30 seconds of tension for two to four reps.

Tip: Move slowly and don't let your body twist, Jacobs says. You can increase the intensity by adding a resistance band around your ankles or attaching a resistance band to an anchor point behind you.

2. Modified plank hold

How to do it:

1. Start in a plank hold with your forearms and toes on the ground.
2. Lower your knees down to the floor.
3. Tuck your pelvis under slightly and engage your abs by drawing your stomach away from your waistband.
4. Keep your shoulders stacked over your elbows and press your forearms down into the floor, pushing your shoulder blades together.
5. Start by holding this plank for about 15 seconds and working your way up to one minute for two to four sets.

Tip: You want to be as active as possible in this exercise, squeezing your muscles to create tension throughout your core, Jacobs says.

3. Jackknives

How to do it:

1. Lie flat on your back with your legs extended out in front of you and your arms extended over your head.
2. Take a deep breath and on your exhale contract your abs, bringing your arms and legs together.
3. Hold for about two to three seconds, and inhale as you lower your arms and legs back down.
4. Mazzucco recommends completing 10 to 12 reps for two to three sets.

Tip: Those just starting out can modify this exercise by bending the knees while reaching forward with straight arms. For those at a more advanced level, keep your legs straight as you reach forward with straight arms.

4. Russian Twists

How to do it:

1. Start in a seated position.
2. Engage your core and lift your feet and hands off the ground.
3. Twist your upper body side to side moving your hands on either side of your legs.
4. If you are using a weight, hold it with both hands and move it from side to side.
5. Try doing two to three sets of 12 to 17 reps, Mazzucco says.

Tip: If you feel an arch in your lower back, you can place your feet on the ground instead of keeping them lifted.

Insider's takeaway

Core strength is important for overall fitness because it helps maintain posture, reduces the risk of lower back injuries, and helps us stay balanced, Mazzucco says.

Everyone is different, so the amount of time it will take to notice a stronger core will vary. For a beginner, strength gains can happen rather quickly, within a few weeks, Jacobs says, however in order to continue gaining strength, you'll need to train, eat, and rest properly.

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