The 21-Day Ab Challenge

Want stronger, flatter abs? Learn how to build a tighter and firmer core with our 21-Day Ab Challenge. Crunch, plank and scissor kick your way to the toned belly you’ve always wanted!

I’m sure you’ve seen them before — taking a three week ab challenge us a big thing over on Pinterest right now!

But most of the time, those challenges have you do a set number of crunches per day and progressively add more. This ab challenge program isn’t like that — this program works every inch of your abs.

Looking for an easy way to get started working out?
Grab our FREE Beginners Workout Guide - 3 Weeks To Tighter Abs, Sculpted Arms, And Toned Legs, by clicking here!

If you do a proper crunch, it can be efficient for building strength, but your abdominals are a dynamic muscle group, and therefore have many different muscles that all need to be strengthened.

This means that in order to reach all parts of your abs, you need to do many different kinds of movements — “crunches” (or spinal flexion), side bending, and rotation are all important for building a strong and aesthetically pleasing mid-section.

First, let’s go over each area of the abs so that you understand how they work and what kinds of motions work each section.

All About Your Abs

Rectus Abdominis

These are the most referred-to muscles in the abdominals, as they are your “six pack” muscles. This muscle is long and flat, and runs vertically between the pubis bone and the lower ribs. It’s responsible for flexing the spine, bringing the ribs and pelvis closer together, and helping to stabilize the core.

Upper Abdominals are the upper section of the rectus abdominis which is responsible for a majority of the flexion of spine closest to the ribs.

Lower Abdominals are the lower section which is more responsible for the the flexion closest to the pelvis. Both the muscles, however, do work in conjunction with each other.

Obliques

The obliques work to rotate the torso and are responsible for bending the spine and torso side to side. They are made of the internal obliques and external obliques.

• Internal Obliques – These are the deeper of the two obliques. The muscle fibers run in an inverted “V” shape.
• External Obliques – The external obliques run closer to the surface of the body and run in a downward “V” shape.

The internal and external obliques create right angles to each other, making them opposite-side rotators. When the trunk rotates left, the external obliques (on the right) contract. When the trunk rotates to the right, the external oblique fibers (on the left) activate the movement.

Transverse Abdominis

This is the deepest layer of abdominal muscles. The transverse abdominal muscle wraps around the torso from front to back and from the ribs to the pelvis. The muscle fibers of the transversus abdominis run horizontally, similar to a corset. This muscle doesn’t help move the spine or the pelvis, but it does help with stabilization and breathing — think planks.

For this reason, it’s important that you focus on strengthening all parts of the abdominals, not just the “six pack” ones. This program will target all areas of your abs.

Don’t Forget your Diet

It’s also important to remember that “abs are made in the kitchen,” so having a proper diet and eating Paleo-friendly foods will help you reach your goal much faster. But don’t worry, we’ve already done all the hard work for you! We’ve prepared a 21-Day Paleo Meal Plan to help on your journey. Check it out here.

Ab Exercises

Crunch

Bring your hands behind your head while laying on your back. Engage your abdominals to bring the knees directly over the hips with a 90-degree bend.

Focus on keeping the lower abs tight and keeping your spine neutral, or just slightly pressing into the mat. Use your upper abdominals to lift the head and chest off the mat.

The trick here is to make sure your abdominals don’t “pooch out” while performing the crunch. Focus on pulling them in, and drawing your navel to your spine. Lower the head and chest back down, and repeat.

Roll Up

Start by laying on your back with arms extended overhead and legs out straight. Engage your abdominals to flatten your lower back into the mat.

Without using momentum, peel your spine off the mat, one vertebra at a time, pulling your navel into your spine. Keep using your abdominals to sit all the way up and reach towards your toes, making a C-curve with your spine.

Slowly lower back down, keeping your heels glued to the mat, and place one vertebra on the mat as you lay all the way back down, reaching the arms back overhead. The key is to make sure you roll SLOWLY through your spine, using your abs, and not “hoisting” yourself up with momentum.

V-Sits

Lay on your back with your arms reaching overhead. Roll one vertebra at a time off the mat as you also lift the legs up, pulling the knees in towards the chest.

Balance on your tailbone as you reach your arms towards your toes. Try to bring your shins parallel to the floor, and focus on lifting your chest and lengthening through your spine. Slowly, and with control, lower back down, one vertebra at a time. Repeat 6-8 times.

Side Plank Hip Lift

Lay on your RIGHT side, stacking your hips and feet. Position your bottom RIGHT elbow directly under your RIGHT shoulder.

Lift your bottom hip off the ground to create a straight line in a plank. Your should be lifting from your bottom oblique and feel a slight pinch in the waistline.

Reach your top hand towards the ceiling or place it on your top hip. Now lower the bottom hip down towards the floor, and lift the hip back up by engaging the lower oblique muscles. Complete all repetitions on the right side before switching to the left.

Scissors

Laying on your back, bring your legs up to the ceiling, with your feet directly over your hips. With your hands behind your head, lift your chest and your head off the mat using your abdominals.

Use the obliques to rotate to the RIGHT, reaching your LEFT elbow to your RIGHT knee, and simultaneously lowering your LEFT leg out straight to hover off the mat. Bring your chest back to the center as you scissor the legs to the other side.

Windshield Wipers

Lay on your back with your arms out in a “T” position and your legs extended straight up to the ceiling. Engage your abdominals and keep your shoulders glued to the floor as you let your legs drop over to the RIGHT a few inches, allowing your left hip to come slightly off the ground.

As you feel like you just start to lose control, use your LEFT side obliques to pull the legs back up to the center, straight up. Repeat on the other side for one full repetition.

Double Crunch

Bring both knees in towards the chest so that the knees are directly over your hips. Place your hands behind your head and lift your head and your chest off the mat.

Keeping the head and chest lifted without straining the neck, extend the legs out into a diagonal position to your point of control. Use the lower abdominals to bring the knees back into the chest, so that the knees are directly over the hips.

Leg Lowers

Bring both legs up to the ceiling as you place both arms down by your side (shown), OR place them behind your head as you lift your upper body into a crunch.

Keep the legs straight as you lower them a few inches, to your point of control. Engage the lower abs and pull the legs back up.

Be sure the lower back doesn’t leave the mat and stays pressed into the mat for the duration of the exercise.

Reverse Crunch

Lay on your back with your arms down by your sides and your legs straight up towards the ceiling. Focus on engaging your lower abs to lift your pelvis and hips off the mat as you press your legs up towards the ceiling a few inches.

With control, lower your hips back down to the floor (don’t just let them drop to the mat). Try not to use too much momentum, and really focus on using the lower abs to control each movement.

The 21-Day Ab Challenge

Complete each exercise with the designated repetitions and sets for each day. You’ll get extra credit if you add in cardio on your “rest days.” Just remember to take at least one rest day each week during the ab challenge.

(Your Next Workout: 6 Stability Ball Exercises to Tone Your Abs)