The split stance—where you’re resting on one knee with an upright torso—is a great tool to apply to core training. This move uses that stance to teach the abs to resist unwanted movement, which helps their function of stabilizing the spine. Pulling the cable from one side asks the abs to work hard to stabilize the torso and keep it from moving. When you perform this exercise, be sure not to allow the hips to move, and remember, it doesn’t take much weight to really get a burn.

How to Do It:

Attach one end of a bar to the lower pulley of a cable station. Hold the bar with both hands so that the cable runs backward and to your right and set yourself up in a split stance: Right knee on the ground, upright torso, left foot on the floor (similar to a lunge position).

Keeping your torso straight up and facing ahead, use both arms to pull the bar out in front of you. Extend it until your right arm is fully extended forward. Slowly return to start position. That’s one rep. After you finish a set, repeat on the other side.

See here for a video demo.

Adding plate transfers to a plank is the ultimate upgrade for the most common core move.

How to Do It:

Stack up to five 2.5- or five-pound plates on the ground, and then get into a plank position. The stack of weights should be next to your left arm.

While maintaining the plank, reach over and pick up a weight with your right arm and place it to your right. Repeat until you’ve stacked all the weights on your right side. Then repeat with your left arm to move the weights back to your left.

See here for a video demo.

Challenging the eccentric (negative) strength of a muscle makes it stronger, since the strongest fibers get the chance to work hard. The dragon flag is one of the most demanding bodyweight core exercises in the game for this exact reason.

How to Do It:

Using a decline bench or flat bench, lie down with your back on the bench and grab onto the back edge of the bench with both hands behind your head. Then raise the entire body up as vertically as possible. There should be a straight line from shoulders to ankles.

Allow your body to descend slowly; resist a quick drop by bracing your abdominals. Keep your butt away from the bench for as long as possible; the body should touch the bench all at the same time, not in parts.

See here for a video demo.

4. Dead Bug

The dead bug is one of those movements where you control the intensity. It’s an unloaded bodyweight movement with no real resistance unless you create it for yourself. The dead bug helps connect the upper body to the lower body so that the abs are capable of properly transferring forces through the entire body during compound movements. They can help everything from the efficiency of your squat to the efficiency of your breathing on a day-to-day basis.

How to Do It:

Find any wall and lay supine on the floor in front of it. With a slight bend in the elbows, apply pressure into the wall, and make sure there are no spaces between the back and the ground. Then, while maintaining that pressure, lift both legs into the air, keeping them bent 90 degrees at the knees.

Next, slowly alternate a “cycle” motion with the legs: Lower each leg down to the floor, one leg at a time (so that your heel touches the ground), and bring it up again. Continue pressing into the wall while doing this. Be hard on yourself and keep strong tension for sets of 30 seconds each.

See here for a video demo.

5. Turkish Get-Up

The Turkish get-up is complex, sure, but you’re not going to find a better exercise to challenge rotary stability, trunk flexion, back strength, and shoulder mobility—all in the same movement. The standard dumbbell or kettlebell Turkish get-up is a winner, especially when performed at the end of your workout as a conditioning drill. If you’re up for a greater challenge, try using a barbell that’s the same weight as the dumbbell or kettlebell you used.

6. Body Saw

If you have access to a TRX or other suspension kit, don’t underestimate body saws; they’re much more challenging than they look.

How to Do It:

Set the TRX handles around one foot off the ground, and place the feet inside while face down. Assume a plank position, and start with the eyes in line with the fists.

Then, slowly allow the arms to “guide” your body backwards until the eyes are in line with the elbows. Be sure not to break form by letting the stomach fall or the back arch. Keep the hips slightly elevated, and remember to engage the glutes. Return to your start position and repeat.

This movement will challenge the anti-extension capacity of the abs and strengthen the lower back in the process, which can fix walking issues and pelvic tilts, not to mention boost basic exercise techniques.

See here for a video demo.