Unilateral Calf Strength Test (Calf Raise Test): Protocol and Reference Tables

The calf raise test (single-leg heel raise) is one of the most widely used tests in sports physiotherapy, especially when assessing and rehabilitating Achilles tendon injuries. It allows you to detect strength-endurance asymmetries between legs that often go unnoticed in a basic clinical evaluation.

What does this test measure?

It measures the maximum number of single-leg heel raises performed through a full range of motion, until technical failure. It assesses strength-endurance of the triceps surae (gastrocnemius and soleus), a key muscle group for propulsion during walking and running, and highly relevant in Achilles tendon rehabilitation.

Equipment needed

• A flat surface, ideally with a step to allow a full range of plantar flexion
• Stopwatch (optional, if using a controlled pace)
• A wall or light support for balance without assisting the movement

Test protocol

1. The subject stands on one leg, with the heel of the standing leg able to drop below toe level (using a step) to allow a full range of motion
2. A hand rests lightly on a wall or surface only for balance, without assisting the movement
3. Perform a full heel raise (maximum plantar flexion) and lower to a full stretch
4. Repeat the cycle at a controlled pace (e.g., 1 rep every 2 seconds) until technical failure (loss of range, pain, or inability to continue)
5. Repeat with the opposite leg and compare both results

Common mistakes

• Using the wall to "push" and assist the movement, instead of just for balance
• Progressively reducing the range of motion without that being considered the end of the test
• Not standardizing the pace, which affects comparability between sides and between assessments

How to interpret the result

Level	Repetitions (non-dominant leg)
Low	< 15
Acceptable	15-25
Good	25-35
Very good	> 35

The most relevant piece of data from this test, especially in Achilles rehabilitation, is the difference between the two legs: an asymmetry greater than 10-15% is usually considered a factor to address before returning to sport after an Achilles tendon or calf injury.

Relationship with other tests

This test relates to other unilateral lower-limb strength tests:

• Unilateral glute strength test (single leg bridge test) — another relevant unilateral assessment within the lower-limb kinetic chain
• Isometric quadriceps strength test — to complete the assessment with another key muscle group

Track progress over time

In Achilles or calf rehabilitation processes, this test is one of the standard criteria for deciding return to sport. In Movalytics you can log repetitions for each leg separately, automatically calculate the percentage difference between them, and track the evolution of symmetry throughout the recovery process.

Frequently asked questions

What difference between legs is considered acceptable? As a general reference, differences below 10% are usually considered acceptable; above 10-15%, it's worth continuing to work on symmetry before progressing to higher-intensity efforts. Is it useful for people without a prior injury? Yes, also as a screening test to detect asymmetries before they cause overload, especially in runners. When is it typically applied in Achilles rehabilitation? Usually in the mid-to-late stages of the process, as one of the objective criteria (alongside others) for progressing toward running and, eventually, return to sport.