There are a few popular exercise options for bodyweight workouts. Find out how to do sit-ups, the risks, and whether they are good.
Sit-ups are an exercise where you start lying down on your back with your feet on the ground. After that, you curl up your upper body until your chest is at your knees.
This movement mainly works your abs and hip flexors.
By doing enough sit-ups with enough resistance you can grow and strengthen these muscles and get all the benefits that come with that.
Many people will find the bodyweight version challenging enough for that but more experienced lifters can consider a variety of weighted sit-ups too.
That aside, one thing to keep in mind is that some people find sit-ups uncomfortable on their spines. If you experience the same, more static exercises like the plank can be better than sit-ups.
How to do a sit-up
One way to make sit-ups at least somewhat more comfortable is by doing the exercise on a soft surface.
That aside, take the following steps to do a sit-up:
- Lie down on your back and put your feet flat on the ground. Hold your arms against your chest.
- Curl up your body in a controlled motion until your chest is close to your knees. Start with your shoulders and as you get closer to your knees more and more of your upper body gets off the ground. Make sure your abs power the movement. Not the swinging of your upper body.
- Slowly curl down your body again. Your lower back goes first and gradually more and more of your upper body touches the ground again.
If you are interested in working your abs, you want to really curl your spine.
Another attention point for sit-ups is not swinging around too much. Keeping your movements slow can help with this.
Sometimes you see people doing sit-ups where they anchor their feet below things like a sofa or partner. This makes it easier to use your hip flexor muscles so generally not recommended if you want to train your abs.
If you are more of an ab workout beginner who can’t do a sit-up yet, you can start with something like crunches instead.
Muscles worked with sit-ups
The main muscles worked with sit-ups are your abs and hip flexors.
Your oblique muscles work just a bit harder compared to something like crunches but likely not enough to really grow and strengthen them.
That aside, keep in mind that you still need to approach sit-ups with a good exercise routine to see results.
There is not really a one size fits all number for how many sit-ups you should do since this depends on what you are trying to achieve.
That being said, something like 3 to 6 sets of 6 to 25 (and potentially even up to 50) sit-ups can be effective for building muscle if you use enough resistance.
Something simple to remember like 100 sit-ups a day could actually offer nice ab muscle growth. Again, if you use enough resistance.
Even if you don’t like the hip flexor engagement or feeling of the movement, it should be clear that sit-ups offer many benefits. A few examples are:
- Stronger muscles: Doing sit-ups in a good exercise routine can make your abs and hip flexors bigger and stronger.
- No equipment or location required: You technically don’t need any equipment to do sit-ups. This can save you some money and transport time.
- May reduce or prevent back pain: Getting stronger core muscles can help reduce or prevent back pain (1, 2). At the same time, people with back pain may want to play it safe and stay away from sit-ups.
- Makes your six-pack stand out more: Growing your ab muscles with sit-ups can make your six-pack stand out more. This is considered to be an aesthetic benefit.
- Somewhat functional: You could experience the sit-up movement in daily life when getting up off the ground. In turn, you can call this exercise somewhat functional.
Sit-ups are not always unique in these areas but the benefits do make it more worth considering this movement.
You may wonder whether there are other exercises that can offer certain benefits of sit-ups.
The answer to that is yes, there are many other good core movements too. A few examples of sit-up alternatives are:
- Bicycle crunches
- Ab wheel roll-outs
- Knee raises on the captain’s chair
- Plank exercises
What sit-up alternatives you will prefer depends on things like the equipment you have, what you want to train, and what movements you are comfortable with.
Is the sit-up a good exercise?
The sit-up is a good exercise for growing and strengthening your ab and oblique muscles.
Many people will find the bodyweight version hard enough but more experienced lifters may need sit-up equipment options to see their desired results.
It is worth briefly mentioning that some people will find sit-ups uncomfortable on their lower backs. For these individuals, more static ab exercises could be a better place to start.
Additionally, not everyone is interested in the additional hip flexor engagement and the slightly bigger ab range of motion.
In that case, something like crunches can be better than sit-ups.
What are sit-ups good for?
Sit-ups are good for working your abs and hip flexors. With enough weight and repetitions, sit-ups can help you grow and strengthen these muscles.