Why This Matters Clinically
The calf complex — gastrocnemius, soleus, and deep posterior compartment (tibialis posterior, flexor hallucis longus, flexor digitorum longus) — controls ankle plantarflexion and provides the tensile force for both propulsion during gait and the energy storage during the stance phase of running. The peroneal muscles (fibularis longus and brevis) control subtalar eversion and are the primary active restraint against ankle inversion sprains. Deficiency in any of these groups produces the cascade of compensatory loading that drives the overuse injuries most common in the lower limb.
Exercise Progression
Single-leg heel raise progression: Phase 1: flat ground, both legs, full plantarflexion. Phase 2: single leg, flat ground, 3-second concentric, 3-second eccentric. Phase 3: single leg, on a step (allow the heel to drop below the step edge for full range), adding load via a backpack when bodyweight becomes easy. 3×12–15 each phase. This is the most important single exercise for calf and Achilles health in any population.
Soleus isolation (bent knee): Single-leg heel raise with the knee bent to 20–30° — this slackens the gastrocnemius (two-joint muscle) and isolates the soleus. Critical since the soleus constitutes 50–55% of the Achilles tendon force during running. 3×12–15 each leg.
Peroneal strengthening (ankle eversion): Seated, resistance band around the foot, evert the foot against resistance (turn the sole outward). 3×15 each ankle. Progress to single-leg stance with the foot on a slight inversion tilt (folded towel or balance board tilted). The peroneal reactive firing is the first line of defence against ankle inversion injuries — training it specifically reduces ankle sprain recurrence.
Banded ankle alphabet: Resistance band around the foot, write the alphabet with the foot — full, complete letters using the maximum ankle range in all planes. Trains the entire extrinsic ankle musculature through its full available range. An effective early-stage rehabilitation and proprioception exercise after ankle sprain.
Achilles tendon length and heel raise range: The range of motion used in heel raise exercises affects which structures are loaded. Full-range heel raise on a step (heel drop below horizontal) maximises Achilles tendon stretch and eccentric load — optimal for midsubstance Achilles tendinopathy rehabilitation. Flat-surface heel raise with no heel drop avoids terminal dorsiflexion compression — optimal for insertional Achilles tendinopathy. Using the correct range for the anatomical presentation is not a minor detail; it is the difference between a therapeutic and an aggravating stimulus.
Programming Guidelines
Train 3× weekly with 48-hour recovery between sessions. Begin at the level where movement quality is excellent and symptoms are 0–2/10. Progress load, range, or complexity only when the current level is performed without compensation across three consecutive sessions. Allow 8–12 weeks for functional strength to meaningfully improve in a rehabilitation context.
References & Further Reading
- Alfredson H, et al. Heavy-load eccentric calf muscle training for the treatment of chronic Achilles tendinosis. Am J Sports Med. 1998;26(3):360–366.
- McGuine TA, Keene JS. The effect of a balance training program on the risk of ankle sprains. Am J Sports Med. 2006;34(7):1103–1111.
- Hintermann B, Nigg BM. Pronation in runners: implications for injuries. Sports Med. 1998;26(3):169–176.