Arnold's Ab Workout: Sculpting The Austrian Oak's Trunk

In 1968, a 20-year-old Arnold Schwarzenegger stepped onstage at the IFBB Mr. Universe—and lost to the razor-sharp Frank Zane. In The Encyclopedia of Modern Bodybuilding, Arnold later admitted the defeat was partly due to his lack of abdominal development and overall definition. He vowed to never let conditioning hold him back again.

And he didn’t.
Between 1970–1975 and again in 1980, the Austrian Oak dominated the Mr. Olympia stage. Behind his iconic chest and boulder shoulders was a high-volume, brutally consistent ab routine that helped tighten his waist and complete his aesthetic.

This guide breaks down:

• Arnold’s exact Mr. Olympia-era ab routine
• Exercise-by-exercise instructions
• His personal training tips
• Insights on posing, waist control, and oblique work
• Modern considerations for anyone trying the routine today

Arnold's Ab Workout

Arnold trained abs at the end of his workouts, often multiple times per week and occasionally twice per day leading into competition. His goal wasn’t extreme blocky abs—it was a tight, controlled midsection that visually shrank his waist while making his chest and arms look even bigger.

His 5-exercise routine targeted:

• Upper abs
• Lower abs
• Obliques
• Overall core endurance

Here is his original routine exactly as written:

Arnold’s Ab Routine (1970s)

• Hanging Knee Raises: 3×25–50
• Roman Chair Sit-Ups: 4×25–30
• Lying Leg Raises: 3×25–30
• Side-to-Side Twist: 3×50
• Seated Leg Tucks: 4×25–50

High reps, minimal rest, and controlled tempo were the cornerstones of his approach.

The Exercises

1. Hanging Knee Raises

The hanging knee raise, a variation of hanging leg raises, is Arnold's favorite move to target the lower portion of the abdominals. Here's how he did it:

1. Hang from a pull-up bar with your hands shoulder distance apart. Your legs should be together, and your knees bent slightly.
2. Pivot from the hips to bring your knees up to your abdominal area.
3. Now, round your back, bringing your knees as high toward your head as possible. You will be trying to roll yourself into a ball.
4. Hold the top contracted position for a second.
5. Lower under control to the start position.

Arnold's Training Tip:

Perform the exercise slowly and deliberately to avoid using momentum to get your knees up.

2. Roman Chair Sit-Up

The Roman Chair, or hyperextension bench, is a padded bench with seat and foot supports designed to allow you to work your core at a range of angles. Here's how to do the Roman Chair Sit-Up:

1. Sit on the bench with your feet hooked under the foot supports. Fold your arms in front of your body.
2. Maintain a tight core as you lower your torso back to a 70-degree angle. Do not go so far that your back is parallel to the floor.
3. Contract your abs to curl your torso as far forward as possible. Fully contract the abs in the top position.

Arnold's Training Tip:

Place a block under the back of the Roman Chair to increase the difficulty of the movement. If your gym doesn't have a dedicated Roman Chair, you can also perform this move on a seated calf raise machine.

3. Lying Leg Raises

The lying leg raise is an exercise that has fallen out of favor with the realization that the abs do not actually attach to the lower body through the legs. As a result, the effect on the abs is minimal. However, Arnold swore by the effects of this move on his lower ab development.

1. Lie on a flat bench on your back with your butt on the end of the bench so that your legs are hanging off the end.
2. Place your hands on the bench by your hips and extend your legs out straight.
3. Without bending your knees, lift your legs as high as possible.
4. Pause in the top position, then lower to just below parallel.

Arnold's Training Tip:

Keep your head up by looking at your feet throughout the movement.

4. Side-to-Side Twist

The side-to-side twist was Arnold's favorite exercise to develop the obliques at the side of the waist. He alternated between the seated and standing bent-over version of the exercise. Here's how to do the seated side-to-side twist:

1. Sit on a bench with feet shoulder-width apart and an unloaded barbell across your shoulders. Hold the bar out wide.
2. Keep your head looking directly ahead as you twist as far to the right as possible.
3. Hold the extreme position for a second, then reverse to twist in the opposite direction.

Arnold's Training Tip:

Rather than swinging back and forth, perform the exercise in a fluid, smooth motion.

5. Seated Leg Tucks

The seated leg tuck (also called the In and Out Abs Exercise) contracts the rib cage toward the pelvis, working both the lower and upper abdominal area.

1. Sit on a bench with your legs together and extend in front of you with knees slightly bent. Hold the sides of the bench for support.
2. Lean back at a 45-degree angle.
3. Simultaneously, curl your torso up as you draw your knees toward your head.
4. Hold the top contracted position for a second and then slowly return to the start position.

Arnold's Training Tip:

Do not allow your feet to touch the floor between reps.

3 More Ab Training Tips from the Austrian Oak

1. Training Frequency

Arnold often performed 500+ reps per session and trained abs several times per week, increasing frequency close to competition.

Modern research supports higher-frequency ab work—as long as recovery is managed.

2. Avoid Heavy Oblique Training

Arnold was not genetically narrow-waisted, so he avoided weighted side bends.

3. Work Abs Last

He saved ab work for last so it wouldn’t fatigue his core before heavy lifts.

Modern lifters still follow this strategy.

Arnold's Ab Posing Strategy

Arnold’s abs were never his standout feature—but his posing mastery turned them into a strength.

He regularly used:

• Waist-twisting poses to create a smaller-waist illusion
• Quarter-turn transitions that emphasized shoulder width
• Vacuum-style breathing to flatten the midsection
• Torso rotation to accentuate biceps and lats

This is why he could outshine more defined competitors—he understood presentation as deeply as training.

Wrap Up

Arnold Schwarzenegger's abs training routine was a product of its time. From a modern perspective, it seems to be very high volume and includes at least one exercise that is frowned upon today. However, there is no denying the results that Arnold was able to achieve with this routine. If you are giving this a shot, you may as well try Arnold's Chest Workout, Back Workout, Shoulders Workout, and Arms Workout.

Why not give it a try and see if it does the same for you?

(All image credit to original owners)