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Doing sit ups correctly: What are the most common mistakes and why we confuse them with crunches

Wondering how to do sit ups correctly? If you answered “yes” to that question, read on. It’s fair to say that sit ups have achieved superstar status and are one of the best workouts to incorporate into any fitness program.

Whether you’ve taken a short break from fitness or are just getting started, we’ve put together an expert list of everything you need to know about ab workouts. You’ll learn how to tone your core muscles, how to perfect your form, and how to avoid the most common ab workout mistakes. We’ll start by explaining the difference between sit ups and crunches, which are often confused.

Sit Ups vs. Crunches – What is the difference?

Wondering how to do sit ups correctly?

Everyone longs for a lean and toned body. But what is the most effective way to achieve this goal: sit ups or crunches?

Sit Ups (Trunk Bends).

Pros: Trains multiple muscles
Trunk squats are a multi-muscle exercise. While they don’t specifically target abdominal fat (note: neither do crunches!), trunk squats work both the abdominal muscles and other muscle groups, including:

  • Chest
  • hip flexors
  • lower back
  • neck

Muscle cells are more metabolically active than fat cells. This means that they burn calories even when they are at rest. By building muscle, trunk squats help you burn more calories in the long run. In addition, strong core muscles can contribute to better posture. Good posture can improve your appearance without the need to lose weight.

Disadvantages: Injuries
The biggest disadvantage of trunk squats is the possibility of lower back and neck injuries. To prevent overuse, consult a doctor for advice if you’ve ever had a related injury.

Workout for abs in bed – here are the best exercises!

Trunk squats are an exercise for multiple muscles

Crunches (abdominal crunches)

Advantages: Intensive muscle isolation
Like sit ups, crunches also help build muscle. However, unlike trunk squats, they work out only the abdominal muscles. This intense muscle isolation makes them a popular exercise for people aiming for a six-pack.

In addition, they are ideal for strengthening the core of the body, that is, the lower back muscles and the oblique abdominal muscles. This way, you can improve your balance and posture.

Disadvantages: Only for the middle of the body
While strong core muscles are a plus for overall fitness, they aren’t necessarily great for everyday movements. Like trunk squats, crunches are good for building muscle, but they don’t burn fat.

Another consideration is your current fitness level. Abdominal crunches build abdominal muscles over time, but can cause significant back pain for beginners. When adding abdominal presses to your workout routine, it’s best to start with 10 to 25 sets and add more sets as you get stronger.

Do Sit Ups Properly

Do sit ups correctly - how to do it

  • Lie on your back.
  • Bend your legs and place your feet firmly on the floor to stabilize your lower body.
  • Cross your hands on your opposite shoulders or place them behind your ears without straining your neck.
  • Bend your upper body down to your knees. Exhale as you lift.
  • Lower slowly and return to your starting point. Inhale as you lower.

Beginners should aim for 10 repetitions each. You can also work your lower legs by bringing your feet together while doing sit-ups!

Perform crunches correctly

Sit ups and crunches are often confused


  • Lie on your back.
  • Bend your legs and stabilize your lower body.
  • Cross the hands on the opposite shoulders or place them behind the ears without straining the neck.
  • Lift the head and shoulder blades off the floor. Exhale as you lift.
  • Lower and return to your starting point. Breathe in as you lower.

It’s best to start with one set of 10 to 25 and add another set as you get stronger.

Sit Ups vs. Crunches - What's the difference?

Summary: Both trunk squats and abdominal crunches are helpful for strengthening and developing trunk muscles. Over time, stronger core muscles can also improve your posture and reduce your risk of back injuries later in life. However, neither exercise burns fat. The only way to get a flat and muscular abdomen is to combine these exercises with a healthy, low-calorie diet and regular, fat-burning endurance training.

Sit up exercises – what is the most common mistake?

Sit up exercises - what is the most common mistake.


Sit-ups can be a tricky thing to do. The traditional sit up can put a lot of strain on your lower back if you perform the exercise on a hard surface, as the floor puts pressure on your spine as it curves.

If you suffer from lower back pain, you should still not continue to perform the sit-ups as this increases the risk of injury. Instead, make sure your exercise program includes movements that strengthen your core without putting pressure on your spine, such as planks.

If you have pain during trunk bends, you should rather do planks

If you suffer from lower back pain and want to try sit-ups, do crunches on a stability ball. Research has shown that a stability ball supports the curvature of the spine, allowing you to use the full range of motion without putting undue stress on your lower back.

Whether you do sit-ups on a stability ball or on the floor, always pay attention to form and not speed. Lowering your body slowly adds an extra dimension of core strength to your workout.

When in pain do crunches on a stability ball

More abdominal workouts can be found here !