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Hamstring and Calf Strengthening

Draftstrength85%intermediate⬤ moderate evidence
View FHIR resourceFHIR R4 ActivityDefinition — the interoperable form of this exercise

Positions & Range of Motion

Start
varies by drill: prone with legs straight for hamstring curls, seated with feet flat for heel raises, or tall kneeling for Nordic eccentrics; spine long and neutral
End
posterior chain fully shortened (heel pulled toward the buttock / heels raised / trunk lowered under control) then returned over ~3 s eccentric
Range of Motion
full available knee flexion (curls), ankle plantarflexion (heel raises), or controlled hip/knee eccentric lengthening (Nordics)

How to Perform

Posterior chain strengthening to balance knee joint forces and improve functional capacity. Includes prone hamstring curls, seated heel raises, and nordic hamstring eccentric exercises. Supports weight-bearing activities and stair negotiation.

Watch on YouTube↗

Opens a YouTube search for “Hamstring and Calf Strengthening”

Starting position: standing

Coaching Cues

  1. 1

    Long, neutral spine — posterior chain shortens then lengthens

    (verbal)
  2. 2

    Pull the heel toward the back pocket

    (verbal)
  3. 3

    Lower over three seconds against gravity

    (verbal)
  4. 4

    Posterior chain works like a fishing line reeling in

    (visual)

Evidence-Based Dosing & EMG Data

Recommended Dosing

3×10-12 reps; eccentric emphasis for tendinopathy (3-4 second lowering)

EMG Activation Data

Nordic hamstring exercise: highest hamstring activation among eccentric exercises; semitendinosus significantly higher [Sahinis 2025]

Muscles Involved (5)

Primary Movers

Hamstrings (Group)— Knee flexion and co-contraction for joint stability
Gastrocnemius— Plantarflexion and weak knee flexion
Soleus— Plantarflexion for push-off in gait

Lengthened / Stretched

Quadriceps Femoris— AUDIT: Prone hamstring-curl component flexes the knee; quadriceps are the untrained direct antagonist genuinely lengthened by knee flexion.
Tibialis Anterior— AUDIT: Seated heel-raise (plantarflexion) component; TA is untrained antagonist stretched, same clean relationship as an isolated heel raise.

Easier Variations ↓

1

Seated Hamstring Curl

Use a seated hamstring curl machine or band. Less balance demand than prone.

2

Double-Leg Heel Raise

Standing bilateral heel raises with wall support. Build calf endurance before progressing.

3

Regress to heel-raise

AUDIT: Build calf endurance with double-leg heel raises before combined posterior-chain work.

Harder Variations ↑

1

Nordic Hamstring Curl

Kneel with ankles anchored, slowly lower body forward using eccentric hamstring control. Gold standard for hamstring eccentric strength.

2

Single-Leg Heel Lower off Step

Rise on two legs, lower on one leg off a step edge. Eccentric calf loading for Achilles and functional strength.

3

Progress to nordic-hamstring-curl

AUDIT: Advance to eccentric Nordic once prone/seated hamstring curls are tolerated pain-free; Nordic is listed as posterior-chain-strengthening's progression.

Target Movements (2)

Knee FlexionTibiofemoral Joint
Ankle PlantarflexionTalocrural Joint

Why This Exercise Matters

Everyday activities this exercise helps you do — essential means it directly trains the capacity the task needs:

WalkingStair ClimbingRunning and Jogging

Goals This Helps With

Rehab, performance, prevention, and mobility goals this exercise supports — essential means it's a cornerstone:

Improve Posterior-Chain StrengthperformanceHamstring Strain Recoveryrehab⚠Hamstring Injury PreventionpreventionKnee Osteoarthritisrehab

Research Notes

Evidence: posterior chain strengthening balances knee joint forces and improves functional capacity [VA 2020, Zeng 2022]. Supports weight-bearing activities and stair negotiation.

Evidence Sources (4)