Target tension.: Whether the muscle you’re training is what gives out first, not your grip, balance or other muscles.
Loaded stretch.: How hard the muscle works while stretched. Training it there is linked to more growth.
Progression.: How easily you can keep adding weight in small steps over months and years.
Low cost.: How easy it is on your joints and recovery, and how quickly you can learn it.

The research score comes from these, scored by hand from the studies. Lifter scores appear once an exercise has 10 ratings. How scores work

When each one fits

Good reasons to choose crunch

You have no equipment
You want something easy to learn
You want something easier on your joints

Good reasons to choose dragon flag

You want more load on the abs while they’re stretched
You want to keep adding weight in small steps

Crunch

Dragon Flag

You need

Nothing but the floor

Bench

Skill

Easy to learn

Needs coaching

Type

Isolation

Questions

Which is better for your abs, crunch or dragon flag?

For your abs, the two are close. Dragon flag rates slightly higher: more stretch, easier to progress. Crunch is easier on the joints.

Is crunch or dragon flag easier to learn?

Crunch is easier: it’s easy to learn, while dragon flag needs coaching.

Can you do crunch or dragon flag at home?

Crunch needs no equipment, so you can do it anywhere. Dragon flag needs a bench, so a home gym covers it.

Which is easier on the joints, crunch or dragon flag?

Crunch: it rates Excellent for joint and recovery cost in our research rubric, against Fair for dragon flag.

More comparisons

Crunch Dragon Flag All abs exercises

Crunch vs Dragon Flag

For your abs, the two are close. Dragon flag rates slightly higher: more stretch, easier to progress.

Crunch is easier on the joints.

What these mean

Target tension.: Whether the muscle you’re training is what gives out first, not your grip, balance or other muscles.
Loaded stretch.: How hard the muscle works while stretched. Training it there is linked to more growth.
Progression.: How easily you can keep adding weight in small steps over months and years.
Low cost.: How easy it is on your joints and recovery, and how quickly you can learn it.