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Heavy Slow Resistance (HSR) for Achilles Tendinopathy

Draftstrength95%intermediate⬤ strong evidence
View FHIR resourceFHIR R4 ActivityDefinition — the interoperable form of this exercise

Positions & Range of Motion

Start
standing with a loaded barbell across the shoulders, balls of the feet on a platform edge and heels dropped below it into dorsiflexion (straight-knee variant; bent-knee/leg-press variants biasing soleus)
End
full ankle plantarflexion up onto the toes, then a slow controlled lowering back below the platform, ~6 s per rep
Range of Motion
below-neutral dorsiflexion (heel dropped) to full plantarflexion under heavy slow load

How to Perform

Progressive heavy resistance training including seated calf raise (bent knee), standing barbell calf raise (straight knee), and leg press calf raise (straight knee). 6 seconds per rep. 12-week progression from 3×15 to 4×6 with increasing load. Equivalent clinical outcomes to Alfredson with superior compliance (92% vs 78%) and patient satisfaction (100% vs 0% at 12 weeks).

Watch on YouTube↗

Opens a YouTube search for “Heavy Slow Resistance (HSR) for Achilles Tendinopathy”

Equipment:barbellcalf raise machineleg press machine
Starting position: standing

Coaching Cues

  1. 1

    Long line through the calf — slow tempo loads the tendon

    (verbal)
  2. 2

    Take three slow seconds up, three slow seconds down

    (verbal)
  3. 3

    Drop the heel below the platform on each rep

    (verbal)
  4. 4

    Bar settles evenly across both shoulders

    (tactile)

Evidence-Based Dosing & EMG Data

Recommended Dosing

12-week progression: Wk1 3×15, Wk2-3 3×12, Wk4-5 4×10, Wk6-8 4×8, Wk9-12 4×6. 6 seconds per rep. 3 exercises per session [Beyer 2015]

EMG Activation Data

Both HSR and eccentric reduce tendon thickness and neovascularization. HSR shows greater collagen turnover evidence and may be more likely to produce tendon adaptation [Malliaras 2013]

Muscles Involved (3)

Primary Movers

Gastrocnemius— Standing and leg press variations — straight knee
Soleus— Seated variation — bent knee isolates soleus

Stabilizers

Tibialis Posterior— Ankle stabilization during heavy loading

Easier Variations ↓

1

Alfredson Eccentric Protocol

If HSR equipment is unavailable, eccentric heel drops on a step achieve equivalent outcomes [Beyer 2015].

2

Bilateral Calf Raises

Start bilateral before progressing to single-leg or loaded variations.

3

Regress to heel-raise

AUDIT: Build calf endurance with bilateral bodyweight heel raises before heavy loaded HSR (HSR's stated bilateral regression).

Harder Variations ↑

1

Increased Load

Continue progressing weight beyond the 12-week protocol. Follow standard progressive overload principles.

2

Plyometric Calf Work

Add hopping and jumping progressions for return-to-sport after completing the 12-week protocol.

Target Movements (1)

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:

Achilles Tendinopathyrehab⚠Running Injury Preventionprevention

Evidence Sources (6)