This challenging series of ab exercises hits upon all of the jobs our abs do.

A note about stability and mobility: most exercises exhibit both, but one of the two is considered the more dominant characteristic for each movement.

Shin Balance Leg Lowering

(Slow-Stability-Flexion/Extension) 10-15 reps https://www.youtube.com/watch?v=LdTA6bwGXLM

Performance Tips:

• Extend and lower the legs only as much as the stability of your abs will allow. Any increase or decrease in the space between your low back and the ground means your abs are not maintaining a neutral low back. Once that starts to happen, you’ve gone beyond the limit of your range of motion.
• The ball resting on the shins forces you to move slowly so pay attention to the feedback the ball provides.

Tripod Plank with Leg Switch 

(Fast-Stability-Flexion/Extension) 20-30 seconds https://www.youtube.com/watch?v=lvboGk9dI8k

Performance Tips:

• Maintain stiffness in the trunk and support leg.
• Adjust work interval time as necessary to provide a challenge while allowing for solid performance. When your abs fatigue you’ll notice the early signs of slight arching in your low back. This should be avoided. It’s best to perform really well on a shorter work interval rather than perform poorly on a longer one.

Torso Offset Crunch on Ball

(Slow-Mobility-Flexion/Extension) 12-18 reps https://www.youtube.com/watch?v=JvgPlMZMezU

Performance Tips:

• The recommendation to avoid crunches is an overstatement of their relative risk. This variation ignites more of your ab muscles by putting you slightly off-center from the ball.
• You only need a very small shift to make this work. Less is more.
• Move with slow, controlled intention through full range of motion.
• Perform three reps shifted to one side; then perform the next three reps shifted to the other side. Continue alternating in this manner until you’ve finished the set.

Mt. Skater

(Fast-Mobility-Flexion/Extension and Rotation) 30 seconds https://www.youtube.com/watch?v=Pn_rWyNSUuQ

Performance Tips:

• Try to create a little hang time and land with each foot wide.
• When tucking the bent leg in, use the momentum from the quick movement to reach the bent knee toward the opposite arm.
• Keep your hips low when you land as they may tend to creep up if you allow your feet to move closer to your hands.

Lateral Rolling Plank on Ball

(Fast-Mobility-Rotation) 8-12 reps per side, alternating https://www.youtube.com/watch?v=G4-1JPscVyA

Performance Tips:

• The start isn’t the hardest part; it’s the sides. You’ll need to hit the brakes as your body rotates around to finish with the ball on the back of your upper arm.
• As soon as you stop rotating one way, reverse direction immediately. If you stop for too long, you’ll lose the stored energy in your muscles that you need to smoothly begin rotating to the other side.

Iso-Tuck Knee Tuck

(Slow-Mobility-Flexion/Extension) 12-15 reps with each leg tucked https://youtu.be/Od7Gu6vP7IE

Performance Tips:

• Tuck the non-moving leg in as far as you can. This helps work the abs harder on that side and also helps prevent any loss of integrity in low back position when your other leg extends.
• Move at a controlled tempo and resist the urge to speed up to finish as you fatigue. Ensure every movement of your body is happening because you are creating it rather than allowing momentum to move you