Sit Up
The sit-up is a fundamental bodyweight core exercise that involves lifting your torso from a lying position to a fully upright seated position. It effectively strengthens the rectus abdominis while engaging the hip flexors and stabilizing the lower back.
Since Sit Ups heavily recruit the hip flexors, Iridium tracks fatigue for that specific sub-group to ensure this movement doesn't negatively impact your lower body recovery. The AI monitors your performance relative to body weight to confirm progressive overload trends even without external resistance. If your 7-day history indicates unrecovered hip flexors, Iridium may substitute this for a crunch variation to better isolate the abs.
Form Cues
- Lie on your back with knees bent and feet flat on the floor
- Cross your arms over your chest or place fingertips lightly behind ears
- Exhale forcefully as you curl your spine off the floor vertebrae by vertebrae
- Sit all the way up until your chest is near your knees
- Inhale as you lower your torso back down with control
- Don't pull on your neck or head with your hands
- Don't slam your back onto the floor on the way down
- Don't swing your arms to generate momentum
- Don't arch your lower back excessively at the starting position
- Don't lead the movement with your chin
Common Mistakes
- Pulling on the neck
- Using momentum to swing up
- Slamming back down to the floor
- Leading with the chin
- Lifting the hips off the floor
Muscles Worked
The sit-up primarily targets the rectus abdominis, the 'six-pack' muscle, by flexing the spine to lift the torso. It also heavily recruits the iliopsoas (hip flexors) to complete the full range of motion into the seated position, making it a compound movement for the anterior chain.
Primary
Secondary
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