Pinpoint
Muscles/Lower Leg

Lower Leg

flexor digitorum longus

FLEK-sor dij-ih-TOE-rum LON-gus

The flexor digitorum longus is a powerful muscle in the deep posterior compartment of the lower leg, running from the tibia down to the toes. It flexes the four smaller toes and assists in plantarflexion at the ankle, helping with push-off during walking, running, and jumping. Strong flexors like this are crucial for balance, propulsion, and preventing foot drop in athletes.

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Common Pain & Injury

Pain from flexor digitorum longus often feels like a deep ache in the calf or inner ankle, worsening with toe pointing or pushing off. Common issues include tendinopathy from overuse in runners or dancers, leading to swelling or pain along the tendon path. See a doctor if pain persists with rest, swelling increases, or you have numbness suggesting nerve involvement.

Anatomy & Function

Origin

Posterior surface of tibia (back of shin bone) below soleal line

Insertion

Distal phalanges of toes 2-5 via quadratus plantae and flexor digitorum longus tendon (tips of smaller toes)

Actions

  • Toe flexion (curling smaller toes)
  • Plantarflexion (pointing foot downward)
  • Foot inversion (turning sole inward)

Innervation

Tibial nerve

Muscle Relationships

Antagonists

Extensor digitorum longusPeroneus tertius

Synergists

Flexor hallucis longusTibialis posterior

Trigger Points

Trigger points form in the calf belly and refer pain to the bottom of the foot, toes 2-5, and sometimes the heel or ankle.

Stretches

1Seated calf stretch with toe extension
2Kneeling ankle dorsiflexion stretch
3Downward dog toe spread

Common Conditions

Flexor digitorum longus tendinopathyPosterior tibial tendon dysfunction

Anatomical Parts

Left flexor digitorum longusRight flexor digitorum longus

FAQ

What does flexor digitorum longus do?

It flexes the smaller toes and helps point the foot downward, essential for push-off in running and jumping.

Flexor digitorum longus pain when walking

Pain often stems from tendinopathy due to overuse; rest, ice, and strengthening calf muscles usually help.

Flexor digitorum longus stretch

Try a seated calf stretch while keeping toes extended backward.

Where is flexor digitorum longus located?

Deep in the calf, from the back of the tibia to the smaller toes.

Exercises for flexor digitorum longus

20
Ankle Circles position 1
Ankle Circles position 2

Ankle Circles

beginner
Anterior Tibialis-SMR position 1
Anterior Tibialis-SMR position 2

Anterior Tibialis-SMR

intermediate·other
Balance Board position 1
Balance Board position 2

Balance Board

beginner·other
Barbell Seated Calf Raise position 1
Barbell Seated Calf Raise position 2

Barbell Seated Calf Raise

beginner·barbell
Bottoms-Up Clean From The Hang Position position 1
Bottoms-Up Clean From The Hang Position position 2

Bottoms-Up Clean From The Hang Position

intermediate·kettlebells
Cable Wrist Curl position 1
Cable Wrist Curl position 2

Cable Wrist Curl

beginner·cable
Calf Press position 1
Calf Press position 2

Calf Press

beginner·machine
Calf Press On The Leg Press Machine position 1
Calf Press On The Leg Press Machine position 2

Calf Press On The Leg Press Machine

beginner·machine
Calf Raise On A Dumbbell position 1
Calf Raise On A Dumbbell position 2

Calf Raise On A Dumbbell

intermediate·dumbbell
Calf Raises - With Bands position 1
Calf Raises - With Bands position 2

Calf Raises - With Bands

beginner·bands
Calf Stretch Elbows Against Wall position 1
Calf Stretch Elbows Against Wall position 2

Calf Stretch Elbows Against Wall

beginner
Calf Stretch Hands Against Wall position 1
Calf Stretch Hands Against Wall position 2

Calf Stretch Hands Against Wall

beginner
Calves-SMR position 1
Calves-SMR position 2

Calves-SMR

intermediate·foam roll
Donkey Calf Raises position 1
Donkey Calf Raises position 2

Donkey Calf Raises

intermediate·other
Dumbbell Lying Pronation position 1
Dumbbell Lying Pronation position 2

Dumbbell Lying Pronation

intermediate·dumbbell
Dumbbell Lying Supination position 1
Dumbbell Lying Supination position 2

Dumbbell Lying Supination

intermediate·dumbbell
Dumbbell Seated One-Leg Calf Raise position 1
Dumbbell Seated One-Leg Calf Raise position 2

Dumbbell Seated One-Leg Calf Raise

beginner·dumbbell
Farmer's Walk position 1
Farmer's Walk position 2

Farmer's Walk

intermediate·other
Finger Curls position 1
Finger Curls position 2

Finger Curls

beginner·barbell
Foot-SMR position 1
Foot-SMR position 2

Foot-SMR

intermediate·other

Also Works flexor digitorum longus

10
90/90 Hamstring position 1
90/90 Hamstring position 2

90/90 Hamstring

beginner·Bodyweight
Alternate Hammer Curl position 1
Alternate Hammer Curl position 2

Alternate Hammer Curl

beginner·dumbbell
Alternate Incline Dumbbell Curl position 1
Alternate Incline Dumbbell Curl position 2

Alternate Incline Dumbbell Curl

beginner·dumbbell
Alternate Leg Diagonal Bound position 1
Alternate Leg Diagonal Bound position 2

Alternate Leg Diagonal Bound

beginner
Alternating Hang Clean position 1
Alternating Hang Clean position 2

Alternating Hang Clean

intermediate·kettlebells
Atlas Stone Trainer position 1
Atlas Stone Trainer position 2

Atlas Stone Trainer

intermediate·other
Atlas Stones position 1
Atlas Stones position 2

Atlas Stones

expert·other
Axle Deadlift position 1
Axle Deadlift position 2

Axle Deadlift

intermediate·other
Backward Drag position 1
Backward Drag position 2

Backward Drag

beginner·other
Ball Leg Curl position 1
Ball Leg Curl position 2

Ball Leg Curl

beginner·exercise ball

Related Lower Leg Muscles

extensor digitorum longus
The extensor digitorum longus runs lateral shin from knee to foot, extending toes 2-5 and dorsiflexing ankle. Builds shin definition for runners.
extensor hallucis longus
The extensor hallucis longus runs down the front of the lower leg and extends the big toe while also assisting in dorsiflexion of the ankle. It's crucial for clearing the foot during the swing phase of gait in runners and athletes. Strong EHL prevents foot drop and enhances explosive movements like jumping.
fibularis brevis
The fibularis brevis, aka peroneus brevis, lies low on the outer lower leg and everts the foot while plantarflexing it. It's essential for lateral stability in running, surfing, or agility drills. Fitness athletes strengthen it to prevent ankle rolls.
fibularis longus
The fibularis longus runs along the outer lower leg, crossing under the foot to evert and stabilize the arch. It powers push-off in sprinting and side-to-side movements. Crucial for runners to avoid ankle sprains and maintain foot alignment.
fibularis tertius
The fibularis tertius is a small muscle on the front-outer lower leg that assists in dorsiflexion and eversion. It's active in quick foot lifts during running or hiking. Often absent, but when present, aids ankle agility in sports.
flexor hallucis longus
Running deep in the calf's posterior compartment, the flexor hallucis longus flexes the big toe and plantarflexes the ankle. It's essential for powerful push-off in sprinting, ballet, and hill running. Athletes rely on it for toe grip on uneven terrain.
gastrocnemius
The gastrocnemius forms the visible calf bulge, crossing knee and ankle for explosive plantarflexion. Key for sprinting, jumping, and calf raises. Two heads make it powerful for athletic propulsion.
plantaris
The plantaris is a thin, vestigial calf muscle aiding knee flexion and plantarflexion, like a minor gas pedal muscle. Often ruptured without issue due to redundancy. Useful for explosive calf power in jumping.

Lower Leg Pain Guide

Common causes and relief

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Activities & Sports

See which activities use flexor digitorum longus

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Pinpoint·Interactive 3D Anatomy & Exercise Guide