How Often Should You Do Abdominal Exercises?

If you're looking to tone and tighten your midsection, it's not about simply doing endless sit-ups for abs. Rather, your abs workout should be just one element of a well-rounded diet and fitness regimen.

Aim to do abdominal exercises at least twice a week — and you may wish to do more. By adding on a few minutes of ab training to any of your workout routines, you can achieve even better results.

The Physical Activity Guidelines for Americans recommends that adults strength-train all major muscle groups at least twice a week. You can either perform total-body strength training twice a week, or break up your workouts to isolate muscle groups on different days. Many people choose to add a few minutes of ab training to their daily workouts.

According to Harvard Health Publishing, your abs are made up of several muscles around the navel, including:

• Rectus abdominis muscles in the front of your abdomen
• Obliques in the front and sides of your abdomen
• Transverse abdominis across your lower abdomen

Furthermore, your abs are part of your core, which includes several muscles that work to stabilize your body and provide a firm foundation for everyday living. There are 29 different muscles that attach to the core, according to the National Academy of Sports Medicine. It's comprised of not only your abs, but also the muscles along your spine, near your shoulder blades, in your pelvis, and in your hips and buttocks.

It's important to train all of your core muscles, not just your abs, as part of a well-rounded ab-training routine. A strong core will allow you to perform a variety of exercises, such as squats, deadlifts and shoulder presses. It also improves your posture and makes it possible to bend down, twist, walk and balance without falling.

Read more: The Best Strength-Training Exercises for Weight Loss

You don't need any special equipment for an ab-training routine — just your body weight will do. Try incorporating the following exercises into your workout. Perform each movement for about 30 seconds to a minute.

Move 1: Basic Crunch for Rectus Abdominis

1. Lie down on your back with your knees bent and aligned over your ankles.

2. Bring your elbows out wide, with your fingertips lightly supporting your head from behind.

3. Exhale as you lift your chest, shoulders and head off the ground, inhale to lower —

   and then repeat.

4. Keep your lower back sealed down on the ground as you work.

Move 2: Bicycle Twist for Obliques

1. Begin in the same starting position as the basic crunch, but lift your feet off the ground so your knees are stacked over your hips.
2. Extend your left leg out straight to hover off the ground.
3. Exhale and twist to tap your left elbow to your right knee; inhale everything back to center. Then exhale and switch to the other side.
4. Repeat several times, moving from side to side; avoid pulling on your neck.

Move 3: Glute Bridge for Transverse Abdominis

1. Lie down on your back with your knees bent, as with basic crunches.
2. Hollow out your abdomen and exhale as you lift your buttocks off the ground.
3. Hold for a second or two, then inhale to lower back down and repeat.

Try different plank variations for your entire core, such as high plank on your hands and feet, forearm plank on your forearms and feet, and side plank where you're balanced on either your hand or your forearm.

Once you've mastered these basic exercises, you'll have a strong foundation to incorporate a variety of abdominal and core exercises into your routines. With a strong core, you'll also perform other types of strength-training exercises with greater ease.

Read more: 5 Benefits of Abdominal Strength & Endurance

If you're looking to tighten your abs, be aware that you cannot spot-reduce fat, as Johns Hopkins Medicine notes. Exercises like sit-ups for abs may strengthen the muscles around your midsection, but they're not enough to trim belly fat.

Instead, focus on a healthy diet and exercise routine that works out your entire body. In addition to strength training twice a week, aim to do at least 150 to 300 minutes of moderate-intensity activity weekly, such as walking. You can also do 75 to 150 minutes of more vigorous activity, such as running or circuit training.

The key for fat loss is to create a negative energy balance in which you start burning fat for fuel, says the International Sports Sciences Association. You can accomplish this calorie deficit through a combination of diet and exercise. The more vigorous the workout, the more calories you'll burn.

For example, walking at 3.5 mph for 30 minutes burns about 149 calories for a 155-pound person. Running burns nearly twice as many calories for that same person, according to Harvard Health Publishing.

Read more: The Ultimate Guide to Sets and Reps for Strength Training

It's to your benefit to lose body fat, especially any fat around your midsection. Abdominal fat is made up of both visceral and subcutaneous fat. Subcutaneous fat is visible — it's the fat you can "pinch" with your fingers — while visceral fat lies deep inside in between abdominal organs, explains Harvard Health Publishing.

Visceral fat is the more concerning of the two, as it may lead to metabolic disturbances and increased risk for cardiovascular disease and Type 2 diabetes. It is also linked with a higher risk for breast cancer and the need for gallbladder surgery.

When you make physical activity and healthy eating a priority, you should begin to see a reduction in both subcutaneous and visceral fat. Focus on a diet of fruits, vegetables, whole grains, lean proteins and polyunsaturated fats; avoid sugary drinks and snacks. Aim to move more and sit less, and in time, you'll achieve the abs — and overall physique — you desire.