Calf Strains in AFL: The Injury That Catches Older Players Off Guard

May 14

The calf strain has a reputation as the older player’s injury, the thing that happens to 30-year-olds who’ve been doing it for 15 seasons. That reputation is partly earned.

But calf strains are increasingly common in younger AFL players, and the reason is almost always the same: a sharp acceleration from a standing start on a cold morning, or a sprint-to-stop sequence late in a long training session.

The Two-Muscle Problem

The calf complex is made up of two distinct muscles that work together but fail differently.

The gastrocnemius is the large, superficial muscle with two heads originating from the femur (above the knee). It is a two-joint muscle, crossing both the knee and ankle, which means it is most vulnerable when the knee is extended and the ankle is loaded simultaneously: exactly what happens during an explosive push-off.

The soleus sits underneath the gastrocnemius and originates from the tibia below the knee. It is a single-joint muscle and the primary workhorse of sustained calf loading during jogging and longer efforts.

Both muscles share the Achilles tendon and attach to the calcaneus (heel bone). The musculotendinous junction of the medial gastrocnemius head is the most common strain site in AFL players.

How It Happens

Two main mechanisms: explosive acceleration from a standing position, and high-speed deceleration during a sprint. In both cases, the calf is loaded eccentrically under high force.

Late in games and training sessions, when fatigue reduces force-absorption capacity, the risk increases significantly.

Grading

Grade 1: Mild strain, no significant structural disruption. Five to ten days. Grade 2: Partial tear, typically at the medial gastrocnemius head. Two to five weeks, depending on extent. Grade 3: Complete rupture. Rare, but requires surgical assessment and 8-12 weeks minimum.

MRI provides the most accurate grading, but ultrasound is adequate for most clinical decision-making.

Treatment

Days 1-3: Heel raise inside the shoe to off-load the tendon, compression, ice, and progressive pain-free weight-bearing. Week 1-2: Progressive range of motion, single-leg standing, seated calf raises. Week 2-4: Standing calf raises, eccentric loading, progressing to walking lunges and step-ups. Week 3-5: Return to jogging, progressive sprint build-up, calf-raise loading at speed.

The most common error is progressing to running too quickly before the muscle can tolerate the eccentric demand of deceleration.

Return to Running

A structured return-to-running program with progressive sprint speeds is essential. The calf should be able to perform 25 single-leg calf raises without pain before starting jogging. Full sprint tolerance without pain or tightness is the criterion for return to training.

Prevention

Calf strength training is the primary preventive strategy. Single-leg standing calf raises, progressing to loaded heel drops with a 10kg pack, reduce calf injury risk significantly. Adequate warm-up before explosive activities and gradual load increases pre-season are fundamental.

For players over 28, managing sprint load in the early weeks of pre-season and maintaining year-round calf training during the off-season is the most effective risk management strategy.

Want to understand this injury at a deeper anatomical level? The Club Physio’s online anatomy course breaks down the structures, biomechanics, and load patterns behind the most common sports injuries. Built for athletes and therapists alike. [Explore the course at theclubphysio.com.au]

josh zoppo