Plank
The plank is a core exercise in which you hold your body in one straight line on your forearms and toes. It trains the abdominal muscles and obliques to hold your low back and hips in place, and it is one of the most common ways to build and measure core endurance.
Also called: Front Plank, Forearm Plank, Prone Bridge, Abdominal Bridge · Equipment: bodyweight · Pattern: isolation
Step by step
- Kneel on a mat and place your forearms on the floor, elbows directly under your shoulders, forearms parallel or hands lightly clasped.
- Step your feet back one at a time, hip-width apart, with your toes tucked under.
- Lift your knees and hips so your body forms one straight line from your ears to your ankles.
- Draw your ribs down towards your hips, brace your stomach and squeeze your glutes so your low back stays flat.
- Push the floor away through your forearms so your upper back stays broad and your shoulders stay lifted.
- Keep your neck long and look at the floor just ahead of your hands.
- Breathe steadily for the whole hold. Finish the set when you can no longer keep the straight line, then rest your knees on the floor.
- One straight line from ears to ankles
- Ribs down, glutes squeezed
- Push the floor away with your forearms
- Elbows under your shoulders
- Neck long, eyes on the floor
- Breathe steadily through the hold
In VALDA, these cues are one tap away on the exercise while you train.
What it trains
| Muscle | Role | Evidence |
|---|---|---|
| Rectus abdominis | Prime mover | C |
| Obliques (internal/external) | Secondary | C |
| Transverse abdominis | Stabiliser | C |
| Erector spinae | Stabiliser | C |
| Quadratus lumborum | Stabiliser | C |
| Hip flexors | Stabiliser | C |
| Gluteus maximus | Stabiliser | D |
| Serratus anterior | Stabiliser | C |
Evidence grades: A = strong research base · B = good · C = limited · D = coaching consensus.
What goes wrong, and the fix
Hips sagging
Fix: Draw your ribs down and squeeze your glutes to bring your hips back into line.
Hips piked up
Fix: Bring your hips down until your body is one straight line from ears to ankles.
Shoulders sinking
Fix: Push the floor away through your forearms to keep your upper back broad.
Holding the breath
Fix: Keep breathing steadily while you hold the brace.
Head dropped or cranked up
Fix: Keep your neck long and look at the floor just ahead of your hands.
Holding on after the line breaks
Fix: End the set when the straight line breaks, and progress to a harder plank.
What the research says
Rehab & prehabGeneral fitnessSport performanceEndurance
- Muscle activity — EMG studies find a standard forearm plank produces moderate abdominal activity. Walking the elbows forward into a long-lever plank, or holding the plank on an unstable surface such as a Swiss ball, raised abdominal activity. EMG measures muscle activity, not growth.
- Core endurance — A timed plank test proved a valid and highly repeatable measure of core endurance in athletes, which is why timed holds are a common way to track progress.
- Hold length — There is no research on the ideal plank duration. A common approach is 2–4 holds of 20–60 seconds, moving to a harder version once a clean 60-second hold feels easy.
- Muscle growth — Research reviews identify mechanical tension and progressive overload as key drivers of muscle growth. A bodyweight plank leaves little room to add load, so many lifters use loaded or dynamic core exercises when abdominal size is the goal.
- Sport transfer — A systematic review found core-stability training on its own gives only small and inconsistent gains in athletic performance measures.
Swap it mid-workout
With VALDA Pro, FLEX offers alternatives like these when you swap an exercise mid-workout.
Log the plank in VALDA, with these cues one tap away while you train and your history for it in one place.
General information about exercise technique, not medical advice. If you have an injury or a health condition, your healthcare provider is the right person to ask.