Never Leave Your Bed!
Functional fitness gurus have demonized the sit-up, saying it's bad for your lower back. Instead, they recommend everyone should do planks and other isometric holds.
Isometric core exercises are fine, but if you think you should get rid of sit-ups altogether, ask yourself this question: What's the first thing you do every morning to get out of bed? You sit up! Sounds pretty "functional" to me.
Why You Should Include Sit-Ups
When performed properly, sit-ups will hypertrophy your abs more than most isometric core movements. Why? The eccentric or "negative" part of the movement, i.e. lowering yourself to the floor. This eccentric lengthening of the rectus abdominis is necessary to maximize the growth of the muscle fibers.
Sit-ups also force you to work your core throughout a whole range of motion. Most isometric holds will only develop "position specific" strength. With sit-ups, you teach your body how to resist back extension or move into flexion from a variety of different angles. This requires proper firing of all your core muscles.
How to Do a Proper Sit-Up
The main cue to focus on is to think of drawing your abdomen in and up. This creates a "lifting" of the torso so you're not crunching your spine as you move into flexion.
If you're unsure what lifting the torso should feel like, try doing band-assisted sit-ups by attaching a band to a high anchor. This modification will help you obtain more of a vertical torso angle and allow you to practice drawing your abdomen in.
Band Assisted Sit-Ups
If you're unable to properly contract your abs to stabilize your lower back, you will over-rely on your hip flexors and could go into violent spinal flexion. Here's what that mistake looks like:
Keep your arms across your chest or reach them overhead if you want to make sit-ups more difficult. Although some people can get away with keeping their hands behind their head, most have the tendency to yank on the back of the neck when they get tired.
Do them with control. If you're violently trying to rep out your sit-ups, you'll tweak your back at some point.
Who Should NOT Do Sit-Ups
- Those with an existing injury or herniated discs.
- People who have poor kinesthetic awareness and those who don't know how to fire their core properly.
- People who over-rely on their hip flexors and an arched lower back due to a lack of core strength.
- Those with an excessive anterior tilt who can't posteriorly rotate the pelvis as they initiate the movement.
Lower Back Friendly Sit-Up Variation
If you struggle with classic sit-ups, perform them on an exercise ball.
Exercise Ball Sit-Up
The ball will squish so that your lower back stays supported.