Strong abs are about much more than aesthetics—they’re the foundation for almost every movement you do. From lifting weights and running to picking up kids or carrying groceries, a strong core helps support your spine, improve stability, and protect against injury. This workout targets your entire midline with a mix of sit-ups, side planks, flutter kicks, and V-ups to build strength and endurance through your abdominals and supporting muscles. The short cardio effort each round keeps your heart rate up, turning this into a powerful 20-minute session that strengthens your core while also improving overall conditioning. Find all of our minimal equipment workouts here.

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Workout Description

At the start of the timer, complete 20 sit-ups. Once finished, move directly into a 30-second side plank on your right side, then switch to 30 seconds on your left side.

Next, complete 20 flutter kicks, followed by 15 V-ups. Finish the round with a 250-meter row.

Once you’ve completed the entire sequence, rest for 60 seconds.

Repeat this pattern for a total of 4 rounds, moving with control and focusing on strong, stable core engagement throughout each movement.

Focus on controlled reps rather than speed—this workout is designed to build core strength and stability, not just fatigue your abs.

Equipment Needed

• Rower

Modification Options

Beginner:

If you are newer to core training, focus on controlled movement and maintaining good form rather than rushing through the reps.

Sit-Ups
Reduce the reps to 10–15 if needed, or substitute crunches if full sit-ups are too challenging.

Side Plank
If a full side plank is difficult, bend your bottom knee and perform a modified side plank from the knee while keeping your hips lifted.

Flutter Kicks
Keep your legs slightly higher off the ground to reduce strain on the lower back. You may also reduce the reps to 12–15 per side.

V-Ups
Modify to bent-knee V-ups or substitute alternating toe touches.

Row (250 meters)
If you don’t have access to a rower, substitute one of the following:

• 200–300 meter run
• 45–60 seconds of jumping jacks
• 45 seconds of mountain climbers

Advanced:

If you’re looking for an additional challenge, increase intensity by adding load or slowing the tempo.

Sit-Ups
Hold a light plate or dumbbell across your chest.

Side Plank
Add a hip dip every few seconds or extend the hold to 40–45 seconds per side.

Flutter Kicks
Lower your legs closer to the floor and slow the tempo to keep constant tension on the core.

V-Ups
Hold a light dumbbell or plate overhead during the movement.

Row (250 meters)
Push the pace and aim to keep each round within a few seconds of your previous effort.

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