Side Plank
Tall through the hip. The side plank builds the side wall of the trunk, holding the body in one line with the glutes, obliques and quads all squeezed. Hips sagging toward the floor is the fault: lift and lock rather than grinding out extra seconds. Side-to-side differences are common, and this is where they show up first.
Setup
- On your side: elbow under shoulder, feet stacked.
- Lift hips until head-to-heels is one straight line.
How To Do It
- Hold with everything squeezed: glutes, obliques, quads.
- Breathe steadily behind the brace.
- 20-40 quality seconds per side.
Breathing
Steady shallow breaths, never held.
Common Mistakes
- Hips sagging toward the floor. Lift and lock.
- Rolling forward or back. Stacked and square.
Programming It
Three holds of 20-45 seconds per side.
Why This Exercise Works
The side plank loads the obliques and the glute medius to resist the body folding sideways. It is the frontal-plane counterpart of the plank, and it is the one people skip, which is why side-to-side trunk differences are so common.
Where You Should Feel It
The obliques and the underside glute holding you from folding sideways. It is the frontal-plane counterpart to a plank and the one almost everyone skips.
Where It Fits in a Program
The plank's harder sibling: the side wall of your core, built one hold at a time. Hold work sits anywhere. Use it as a finisher, or between sets of something heavy.
Progressing and Regressing It
To progress the side plank: lift the top leg, or extend the top arm overhead. To regress it: drop to the bottom knee, or plank against a bench.
Who It's For
Anyone whose trunk training is all front-on. Side-to-side differences are common and this is where they show up.
Equipment and Substitutions
Nothing to buy and nowhere to be, which is the point. If it is too easy, the harder variations below are the progression, not added weight.
Related Exercises
- Band Woodchop · Obliques, Core
- Cable Woodchop · Obliques, Core
- Pallof Press · Core, Obliques
- Kettlebell Windmill · Obliques, Shoulders, Hamstrings
- Bicycle Crunch · Abs, Obliques
- Mountain Climbers · Core, Conditioning
- Bird Dog · Core, Low Back, Glutes
- Reverse Crunch · Abs, Hip Flexors
Common Questions
What muscles does the side plank work?
The side plank primarily trains the obliques, core.
How many sets and reps should I do?
Three holds of 20-45 seconds per side.
What are the most common side plank mistakes?
Most often: hips sagging toward the floor; rolling forward or back.
Can I do this without any equipment?
Yes. This version needs no equipment at all. It trains the obliques, core using bodyweight alone, which is why it travels well and works as a warm-up, a substitute, or a full session on its own.
Is this safe if I have an existing injury?
The lower back does real work in the side plank. If you have a history there, keep the load conservative and stop the moment a rep reproduces your own pain rather than ordinary effort. Not medical advice.