Are Sit-Ups an Effective Exercise for Weight Loss? Here's What You Need to Know

Doing a ton of sit-ups every day isn't exactly our idea of a good time. And it isn't exactly the key to weight loss (if that's your goal), either.

Although core exercises, like sit-ups, will help increase your overall calorie burn, doing sit-ups alone won't lead to significant weight loss, so there's no exact number you should aim for. That's because sit-ups are a resistance exercise, not an aerobic exercise. They help to tone your muscles but don't burn a ton of calories or fat or lead to significant amounts of weight loss.

You'll need to pair some diet tweaks with a regular exercise routine to shed pounds and keep them off.

Sit-ups are a type of calisthenics. This is a broad description of exercises you do with only your body weight. Other examples include push-ups, pull-ups and body-weight squats. Typically, you do one or more sets of a certain number of repetitions and then move on to the next exercise.

While wearing a heart rate monitor is probably the best way to estimate how many calories sit-ups burn, there are other resources you can use. After 30 minutes of calisthenic exercise (like sit-ups), a 155-pound adult burns 167 calories, according to Harvard Health Publishing. Not to mention, spending 30 minutes doing nothing but sit-ups is pretty unrealistic.

This means that you burn just over 5 calories per minute, depending on your heart rate and exertion. So, let's say you do 100 sit-ups. Assuming it takes you 3 to 6 minutes to complete 100 sit-ups, the total burn would be just over 15 calories. Not exactly a game-changer, eh?

Granted, the calorie burn range varies due to differences in individual characteristics like body weight and exercise intensity, according to the Mayo Clinic. The more you weigh, the more calories you'll burn doing a particular activity because it takes more energy to move your body through space.

According to Harvard Health Publishing, the calorie breakdown for 100 sit-ups in 3 to 6 minutes looks like this:

• 125 pounds: 13.5 to 27 calories
• 155 pounds: 16.7 to 31 calories
• 185 pounds: 20 to 40 calories

If you weigh more or less than these numbers, you may burn more or fewer calories.

As we mentioned earlier, there's no specific number of sit-ups you should do each day to lose weight. And doing hundreds of sit-ups per day is unlikely to move the needle (and is an unhealthy way to think about exercise) when it comes to weight loss, if that's your goal.

However, if you want to test your fitness, someone at an average fitness level should be able to do about 20 to 30 sit-ups per minute, according to SelectHealth. Someone at a higher fitness level might be able to do closer to 50 to 60 sit-ups per minute.

It's worth noting, however, that being able to perform a high number of push-ups isn't necessarily a sign you're physically fit. It could actually mean you're performing the exercise incorrectly, which can lead to muscle or joint injuries.

The American Council on Exercise cautions against high-rep abs exercises — if you're able to comfortably perform more than 25 consecutive reps, the probability is high that you're performing the exercise incorrectly. (More on how to perform a sit-up with proper form below.)

Sit-ups can be a part of your workout routine. After all, they strengthen your rectus abdominis (the muscle that runs from your chest to your pelvis), obliques (the muscles on the sides of your rectus abdominis), hip flexors and a number of muscles in your legs.

But sit-ups shouldn't be your only exercise for weight loss. Schedule at least 150 minutes of moderate-intensity cardio, like walking or hiking, each week to not only shed fat but strengthen your heart, too, according to the Centers for Disease Control and Prevention (CDC).

If you like more intense cardio, consider high-intensity interval training or HIIT. By alternating between harder intervals and periods of recovery, you spike your heart rate and torch calories. Plus, you can incorporate those sit-ups into a HIIT workout.

You'll also want to aim for at least two strength-training sessions each week to increase lean muscle mass, which improves your metabolism and helps your body burn more calories, according to Harvard Health Publishing.

When you hit the gym to strength train, prioritize compound movements, recommends the American Council on Exercise. These exercises — like deadlifts, squats and chest presses — activate several muscles at once, building your cardio, muscle and flexibility.

Banging out 100 sit-ups every day for a week isn't a proven way to shed belly fat. If weight loss is your goal, you'll first want to look at your daily diet. To see the number on the scale go down, you need to burn more calories than you take in, creating what's known as a calorie deficit.

Start by determining how many calories you eat each day to stay at your current weight — aka your maintenance calories. To find this value, use a food diary or app to track what you eat over a few days. Given you don't gain or lose any weight, this value will be your maintenance calories.

From there, gradually cut calories to create a deficit. One of the easiest ways to do this is by eliminating high-calorie processed foods. While it's generally safe to cut around 500 calories a day from your diet, according to the Mayo Clinic, this number depends on how many calories you're consuming in the first place. For instance, cutting 500 calories from a 2,200-calorie diet is a lot different than cutting it from a 1,200-calorie diet, with the latter being unhealthy and unsustainable for your energy levels. Always check in with your doctor before making any dietary changes like this.

Fill your plate with plenty of vegetables and fruits of all different colors. Plants are low in calories but high in vitamins and nutrients, according to the Academy of Nutrition and Dietetics. Leafy greens, like spinach and kale, are especially high in fiber, a nutrient that digests slowly so keeps you feeling full for longer.

Get your carbs from whole grains — like brown rice, oats or quinoa — rather than refined sources like bread or pasta. Choose lean sources of protein like poultry and fish; because they're low in fat, they're lower in calories, too.

Some people experience pain in their lower back when they do sit-ups, according to the American Council on Exercise. This could be because you're performing them incorrectly or because of the hard ground pushing into your spine while you do the sit-ups.

Doing too many sit-ups without working out the opposing muscles can also make your hip flexor muscles very tight, which can then pull on your back muscles and cause pain. Traditional sit-ups actually work your hip flexors more than your abs. If this is a problem for you, try other exercises that work your core, like planks or side planks, along with the glute bridge to stretch the hip flexors.

Hundreds of sit-ups each week will definitely burn calories, but doing a single exercise too regularly can lead to overuse and injury (not to mention, it's bound to get boring). Instead, stay consistent with your healthy diet and broader exercise routine and you'll begin to see progress.