Muscle guide · Lower legs
Also called fibularis muscles, peroneal muscles, outer calf muscles
The peroneals, also called the fibularis longus and brevis, are the two muscles on the outside of the lower leg. Their tendons run behind the bony bump on the outside of the ankle.
They turn the sole outward, which is how you catch yourself when the foot starts to roll on uneven ground.
| Part | Starts at | Attaches to | What it does |
|---|---|---|---|
| Fibularis (peroneus) longus | Head and upper outer surface of the fibula | Crosses under the foot to the base of the big-toe bone and the inner midfoot | Turns the sole outward, helps point the foot, supports the arch from below |
| Fibularis (peroneus) brevis | Lower two-thirds of the outer fibula | The bump on the outer edge of the midfoot (base of the fifth metatarsal) | Turns the sole outward and helps point the foot |
Peroneal strengthening and balance work are standard stages of ankle-sprain rehabilitation. In an MRI study a single-leg heel raise worked the peroneus longus strongly.
3D demoBand ankle eversionBeginner · A band + A bench or box
3D demoIsometric ankle eversion against a wallBeginner · A wall + A bench or box
3D demoSingle-leg standBeginner · A wall
3D demoSingle-leg calf raise from a stepIntermediate · A step + A wall
3D demoTandem stance and heel-to-toe walkBeginner · A wallMost sprains are a forced inward roll that injures the ligaments on the outside of the ankle. Severe ones can also tear the peroneal tendons, and the brevis can pull off the bump on the outer midfoot.
In the year after a sprain, the risk of another one is about double.
Tendinopathy, tears and tendons slipping out of their groove behind the outer ankle. They are the most commonly dislocated tendons at the ankle, partly because the groove is shallow in some people.
Each grade rates the evidence for the correction.
Balance practice in 10 minutes: tandem stance, single-leg stands, marches, heel walks, tree pose and floor transfers.
10 minBeginner7 movesA wall, A bench or boxStrength and balance in one session: squats, Romanian deadlifts, push-ups, rows, step-ups, back extensions, carries and single-leg balance.
45 minBeginner14 movesA wall, A dumbbellThey turn the sole outward and steady the ankle, which is how you catch a foot that starts to roll on uneven ground.
Band eversion (turning the foot outward against a band), single-leg balance work and single-leg heel raises.
After a sprain, yes: an 8-week home balance programme cut repeat sprains from 33% to 22% in a randomised trial of 522 athletes.
Anatomy and movement education, not a diagnosis or treatment plan. If you have pain that follows an injury, is severe or getting worse, or comes with numbness, weakness or swelling, get it assessed. Health disclaimer.
