This is a complete 28-day core strength program built around eight ab mat exercises, three training days per week, and a progression designed to take you from foundation to genuinely strong in four weeks. The full program is below. You can start today with no login, no email, nothing gated.

If you want the printable version plus nine bonus materials — workout cards, progress tracker, scaling guide, injury substitutions, and more — that's the free PDF download. The program itself is the same. The PDF adds the tools that make it easier to actually finish.

Most core programs fail for one of three reasons. They're too random to build progression. They're too ambitious and burn people out by week two. Or they have no built-in way to measure whether the work is doing anything. This program solves all three. Week 1 builds your foundation. Week 2 adds volume. Week 3 pushes intensity. Week 4 tests your progress against your Week 1 baseline so you can see the numbers change.

Before you start, one setup reminder. The ab mat only works if you use it right. Curved side up, highest point of the curve just below your shoulder blades, tailbone resting on the tailbone protector pad. Your shoulders should extend past the top of the mat at the bottom of every rep. If you're new to the mat, read How to Use an Ab Mat before starting Week 1. It's also worth reviewing the core training mistakes that kill progress — most people are making at least 3 of the 11 going in. And for a full breakdown of what to buy and what to skip, see the home gym core equipment guide.

Who This Program Is For

This program works for three types of people.

Beginners who've never done structured core training. Start with the beginner variations of each exercise. You'll build strength safely without getting injured or quitting.

Intermediates who train core occasionally but want a real program. You'll notice faster progress than you expect because most occasional training lacks the progressive overload this program builds in.

Advanced lifters who need a focused core block. Use the advanced variations, add weight where noted, and treat the Week 4 tests as actual tests. Your numbers will surprise you.

The program uses three training days per week (Monday, Wednesday, Friday). If your schedule is different, train any three days with at least one rest day between sessions.

The 8 Core Exercises

Every workout in this program uses some combination of these eight movements. Learn them before Week 1. For detailed form cues on each, see Ab Mat Exercises for Beginners.

1. Butterfly Sit-Up

Soles together, knees out. Lower fully onto the mat, sit up, reach forward.

Beginner: Arms crossed, touch knees Intermediate: Arms overhead, touch past feet Advanced: Hold weight plate overhead

2. Ab Mat Crunch

Feet flat, knees bent. Extend back over mat, crunch up until shoulder blades clear.

Beginner: Hands on thighs Intermediate: Hands behind head Advanced: Hands overhead with light weight

3. Oblique Crunch

Same as crunch. Rotate as you curl up, drive elbow toward opposite knee. Alternate sides.

Beginner: Hands on thighs, gentle rotation Intermediate: Hands behind head, full rotation Advanced: Light weight at chest

4. Leg Raise

Lie face up on mat. Raise legs to 90°, lower slowly without arching lower back.

Beginner: Bent knees to chest Intermediate: Straight legs to 90° Advanced: Lower to 6 inches, pause, repeat

5. Prone Back Extension

Flip mat under hips. Lie face down, raise chest by squeezing lower back and glutes.

Beginner: Hands at sides Intermediate: Hands behind head Advanced: Arms extended overhead

6. Plank Hold

Forearms on mat, body in straight line. Mat cushions elbows for longer holds.

Beginner: 20 sec × 3 sets Intermediate: 30 sec × 3 sets Advanced: 45 sec × 3 sets

7. V-Up

Lie flat, arms overhead. Simultaneously raise legs and upper body, reach for toes.

Beginner: Tuck-up (bend knees, meet hands) Intermediate: One leg at a time, alternating Advanced: Full V-up, straight legs

8. Hip Raise

Lie face up, legs straight at 90°. Push hips off floor by squeezing lower abs.

Beginner: Bent knees Intermediate: Straight legs Advanced: Straight legs, 3-sec slow negative

Week 1: Foundation

Focus on form. Learn the movements. Don't chase reps.

Before Day 1: Record your baseline. Do one max-effort set of butterfly sit-ups, one max plank hold, and one max V-up attempt. Write the numbers down. You'll retest in Week 4.

Day 1 — Monday
ExerciseRepsSetsRest
Butterfly Sit-Up10345 sec
Ab Mat Crunch12330 sec
Plank HoldAt your level345 sec
Day 2 — Wednesday
ExerciseRepsSetsRest
Oblique Crunch10 per side330 sec
Leg Raise10345 sec
Prone Back Extension12330 sec
Day 3 — Friday
ExerciseRepsSetsRest
Butterfly Sit-Up12345 sec
V-Up8345 sec
Hip Raise10330 sec
Week 1 focus: If you feel form breaking down, stop the set. It's better to do 7 clean reps than 12 sloppy ones. This week sets the pattern. Do it right.

Week 2: Build

Same exercises. Increase reps by 2–3. Reduce rest by 5–10 seconds. Form still comes first.

Day 4 — Monday
ExerciseRepsSetsRest
Butterfly Sit-Up13340 sec
Ab Mat Crunch15325 sec
Plank Hold+5 sec from Week 1340 sec
Day 5 — Wednesday
ExerciseRepsSetsRest
Oblique Crunch12 per side325 sec
Leg Raise12340 sec
Prone Back Extension15325 sec
Day 6 — Friday
ExerciseRepsSetsRest
Butterfly Sit-Up15340 sec
V-Up10340 sec
Hip Raise12325 sec
Week 2 focus: This is the week most people quit. The novelty wore off, progress isn't visible yet, and the workouts feel harder because they are harder. Push through. The change happens in Week 3.

Week 3: Push

Add a 4th set to two exercises per workout. Continue increasing reps. Reduce rest to 20–30 seconds.

Day 7 — Monday
ExerciseRepsSetsRest
Butterfly Sit-Up15435 sec
Ab Mat Crunch18320 sec
Hip Raise12430 sec
Day 8 — Wednesday
ExerciseRepsSetsRest
Oblique Crunch14 per side320 sec
Leg Raise14435 sec
Prone Back Extension18320 sec
Day 9 — Friday
ExerciseRepsSetsRest
Butterfly Sit-Up18330 sec
V-Up12435 sec
Plank Hold+10 sec from Week 2330 sec
Week 3 focus: This is where you'll notice the change. Movements that were hard in Week 1 feel manageable. Rep counts that seemed ambitious now feel normal. That's your core getting stronger.

Week 4: Test

Benchmark week. Maximum effort on key exercises. See how far you've come.

Day 10 — Monday
ExerciseRepsSetsRest
Butterfly Sit-UpMax reps360 sec
Ab Mat Crunch20320 sec
Plank HoldMax time360 sec
Day 11 — Wednesday
ExerciseRepsSetsRest
Oblique Crunch15 per side420 sec
Leg RaiseMax reps360 sec
Prone Back Extension20320 sec
Day 12 — Friday (Final Test)
ExerciseRepsSetsRest
Butterfly Sit-UpMax reps1
V-UpMax reps1
Plank HoldMax time1
Hip RaiseMax reps1

Write down your numbers. Compare to your Week 1 baseline. The gap between those two numbers is 28 days of work made visible.

What to Do After Day 28

You just finished 28 days of structured core training. That's more than most people do in a year. Three paths forward:

1. Repeat the program at a higher level. If you ran Week 1–4 at beginner, run it again at intermediate. Same exercises, different challenge. Keep progressing.

2. Add weight. Hold a weight plate, dumbbell, or medicine ball during sit-ups, crunches, and V-ups. Even 5–10 pounds transforms the entire program.

3. Integrate into your regular training. Pick 2–3 exercises from this program and add them to the end of your regular workouts. Three rounds at the end of leg day keeps the core work going without requiring dedicated sessions.

Whatever you do, don't stop. The strength you built in 28 days fades if you stop training. Use it or lose it.

Get the Printable PDF + 9 Bonus Materials

The full program above is free to use. The PDF adds the tools that make it easier to actually finish.

  • Complete 28-day program formatted for print
  • 12 printable workout cards (one per training day)
  • 5 bonus ab mat exercises
  • 4-week progress tracker
  • Exercise form cheat sheet
  • Scaling decision tree
  • Month 2 and beyond guide
  • Injury & limitation substitutions
  • Program methodology explained
Download Free →

Why Ab Mat Training Works

If you're going to invest 28 days in this program, it's worth understanding why the ab mat matters. Three reasons.

Extended range of motion. On the floor, your back hits the ground and stops. On the mat, your shoulders extend past the top of the curve, stretching your abs further before every contraction. More range means more muscle activation per rep.

Tailbone protection. Anyone who's done 50 sit-ups on a bare floor knows what happens. Your tailbone gives out before your abs do. The mat's tailbone protector pad lets you complete the workout you actually planned.

Lower back support. The curve follows the natural arc of your lumbar spine at the bottom of the movement. Less strain on the lower back, more comfort through long sets.

For the full comparison, see Ab Mat vs Floor Sit-Ups. If you don't have an ab mat yet, the Athlos Fitness Ab Mat has been the standard in CrossFit gyms, home gyms, and barre studios since 2014 — 4.5 stars across 1,842 verified Amazon reviews.

Frequently Asked Questions

How often should I do this program?
The program uses three training days per week. Keep at least one rest day between sessions. If you want to train more frequently, add light cardio or mobility work on off days, but don't stack additional core work on top of the program.
Can I do this program without an ab mat?
You can do the movements on the floor, but you'll lose the extended range of motion and the tailbone protection that make the program effective. High-rep sets especially become uncomfortable fast on a flat surface.
What if I miss a workout?
Pick up where you left off. Don't try to double up the next session. One missed workout doesn't break the program. Skipping an entire week does.
Is this program safe if I have lower back pain?
It depends on the cause and severity. Several exercises are generally considered safer for back pain than floor sit-ups because the ab mat supports your lumbar spine. Consult your doctor before starting if you have chronic back pain, a herniated disc, or a recent injury. The PDF download includes a substitution guide for common limitations.
When will I see results?
You'll feel stronger in Week 2 and notice visible change in Week 3 if you're training consistently and your nutrition is in the right range. Abs are built in the kitchen and the gym both. The program builds the strength. What you eat determines whether that strength is visible.