With millions of followers across social media and a physique built around elite-level body control, former gymnast Jason Bjarnson has become one of the internet’s go-to sources for advanced core training.

But Bjarnson says he wasn’t always built that way. As a teenager, he describes himself as skinny and self-conscious about his lack of muscle mass before gymnastics and running completely transformed his physique.

Now known for his shredded abs and calisthenics strength, Bjarnson regularly shares advanced bodyweight exercises with his audience – and in a recent Instagram post, he demonstrated five challenging variations of the famous dragon flag exercise.

What Is the Dragon Flag?

Popularised by Bruce Lee, the dragon flag is one of the most demanding bodyweight core exercises you can do.

Performed using a bench or sturdy anchor point, the movement involves lifting and lowering your body while keeping your torso rigid and your shoulders anchored in place.

Alongside building serious abdominal strength, dragon flags also improve full-body tension, posture and body control – qualities that transfer well to movements like push-ups, calisthenics skills and even the human flag.

Here are the five variations Bjarnson recommends progressing through.

1. Bent-Knee Dragon Flag

This beginner-friendly progression reduces leverage by keeping the knees bent.

Position your upper back and shoulders near the top of a bench while gripping firmly behind your head for support. From there, raise and lower your body slowly while keeping your core braced.

Bjarnson says this is the ideal starting point before attempting a full dragon flag.

2. Bent-Knee Dragon Flag with Core Rotation

To increase oblique activation, Bjarnson adds a twist at the top of each rep by rotating the hips slightly from side to side.

Alternating directions with each repetition helps challenge rotational core strength and stability.

3. Alternating Bent-Knee Dragon Flag

This variation shifts emphasis from one side of the body to the other by alternating leg positions throughout the movement.

According to Bjarnson, it’s an effective way to build unilateral control while increasing the challenge on the lower abs and hip flexors.

4. Full Dragon Flag

The classic version requires straight legs, locked-in tension and complete control throughout the movement.

Keeping your legs together and core fully engaged, lower your body slowly while maintaining a rigid line from shoulders to feet.

As with every variation, Bjarnson recommends squeezing both the abs and glutes throughout each rep.

5. Weighted Dragon Flag

For an extra challenge, Bjarnson adds external load to the exercise using weighted ankle straps or by holding a dumbbell between the feet.

This variation dramatically increases the demand on the core and should only be attempted once you’ve mastered the standard movement pattern.