When your workout involves 100 sit-ups in a row, chances are you're pretty fit. But you may be curious to find out how many calories your 100 reps of effort are actually burning.
Spoiler: The total isn't too high. But you can burn more by increasing the challenge of your sit-ups and incorporating them into a fast-paced workout that includes other exercises.
Read more: The Best Home Sit-Ups Workout for Quick Abs
How Many Calories Does 100 Sit-Ups Burn?
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 set number of repetitions and then move onto the next exercise.
While wearing a heart rate monitor is probably the best way to estimate how many calories 100 sit-ups burn, there are other resources you can use. After 30 minutes of calisthenic exercise (calisthenics are bodyweight exercises, like crunches), a 155-pound adult burns 167 calories, according to Harvard Health Publishing.
This means that you burn just over five calories per minute, depending on your heart rate and exertion. 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.
Read more: Exercises That Will Burn 500 Calories
Increasing Your Calorie Burn with Variety
Although performing 100 traditional sit-ups is challenging for most people, you can increase your calorie burn by triggering more of your core and adding some variety to your ab exercises. The American Council on Exercise recommends introducing some of these challenging moves to your next ab session.
1. Seated Hip Hinge
- Begin seated on the floor, knees bent and heels touching the floor.
- Cross your arms over your chest, keeping them relaxed.
- Hinge at your hips so your torso leans back to a 30-degree incline.
- Hold this position for 30 seconds.
To increase the challenge, lean back as far as possible, keeping the back straight. Or, raise your legs off the ground for more instability.
2. Hollow Rock
- Lie on your back with arms extended overhead, legs straight out.
- Lift into a "hollow" position, with arms and legs up, lower back pressed into the ground and head in line with the arms. Engaging your core, start rocking your body forward and backward (you'll look like the bottom of a rocking chair).
- Perform these rocks for 30 seconds.
3. Side Plank
- Lie on your right side, placing your right hand underneath the right shoulder and balance on the edge of the right foot. Stack the left foot on top of the right.
- Reach your left arm up toward the ceiling.
- Using your right-side obliques, actively lift the body up and away from the floor.
- Hold for 30 seconds; repeat on the other side.
4. Mountain Climber
- Begin in a plank position, hands directly beneath the shoulders, body in a straight line from head to hips to toes.
- Bring one knee toward your chest, keeping the foot flexed, and then return your leg next to the other.
- Alternate with the opposite leg.
- Continue alternating legs as quickly as you can while keeping your body in line for 60 seconds.
This exercise adds more intensity to your core workout, which will add to your 100 sit ups higher calorie burn.