Introducing the Power Carriers of Human Performance

When it comes to locomotion, very few structures can be defined as fundamental in carrying over the responsibility of efficient performance as the intrinsic and extrinsic muscles of the foot.

Defining efficient performance within the context of human locomotion involves considering a mix of biomechanical (i.e. shock absorption, pressure distribution, force transmission), neural (the neuromechanical interactions underlying neural control of movement), and technical factors.

I have introduced the concept of power carriers of performance as it relates to the activity of the intrinsic and extrinsic muscles of the foot to drive the expression of several micro-movements within the context of macro-movements to allow for the necessary joint translation and stability required for energy absorption and force transmission.

What we have to realize is that while large lower extremities muscles such as the glutes, hamstrings and quads are pivotal in generating the large forces required to move our center of mass forward, this can only be accomplished through the complex and finely tuned interactions between 20 muscles, 107 ligaments, and 33 joints.

While multiple muscle groups must be efficiently engaged to regulate, buffer, and produce propulsive forces, their overall impact on whole-body momentum is ultimately determined by the interaction with the ground. Notably, a characteristic of bipedal locomotion is that the substantial forces generated from dynamic limb repositioning during the flight phase must be transmitted between the body and the ground through the relatively limited surface area of the foot. The foot functions as the sole point of contact with the ground during both walking and running activities.

Here the concept of power carriers arises from: the large muscles surrounding the hip generates force and power, while the foot provides to translate the force generation in an efficient movement outcome.

The Five Power Carriers

I have identified the five power carriers as follows: tibialis anterior, tibialis posterior, gastrocnemius, soleus, and peroneals.

Tibialis Anterior

The tibialis anterior is a long, fusiform muscle located on the anterior aspect of the leg, lateral to the tibia’s anterior border.

Its primary function is dorsiflexion of the foot at the ankle joint, and together with the tibialis posterior, it contributes to inversion of the foot by turning the sole medially

Like other leg muscles, the tibialis anterior plays a critical role in maintaining postural balance on the foot. It acts in conjunction with adjacent musculature to stabilize the body during upper body movements that alter weight distribution.

What is the Power Carrier Function of Tibialis Anterior?

During the stance phase, the tibialis anterior helps keep the forefoot inverted around the longitudinal midtarsal joint axis at foot strike and during midstance. Additionally, at terminal stance and into early swing phase, contraction of the tibialis anterior aids in dorsiflexing the ankle.

Tibialis Posterior

The tibialis posterior is the deepest muscle within the posterior compartment of the leg, originating from the upper half of the lateral aspect of the posterior surface of the tibia, situated below the soleal line. Alongside the tibialis anterior, the tibialis posterior serves as a primary invertor of the foot. This muscle plays a crucial role in maintaining the alignment of the tibia on the foot, especially when body weight shifts laterally. Due to its strength as an invertor, it regulates the positioning of the forefoot during gait, ensuring that the medial longitudinal arch remains supported and does not collapse entirely.

What is the Power Carrier Function of Tibialis Posterior?

In the early stance phase, the tibialis posterior muscle plays a crucial role in decelerating subtalar pronation. As the stance progresses, it works together with the gastrocsoleus complex and the Achilles tendon to plantarflex and invert the foot, supporting effective propulsion. At impact, when the foot contacts the ground, supination helps absorb energy efficiently, and the subtalar joint needs mediolateral stability—this is provided by the eccentric contraction of the tibialis posterior. If this muscle becomes fatigued, it can disrupt the entire gait cycle as well as proper foot function during running and sprinting.

Gastrocnemius

The gastrocnemius muscle is located on the posterior aspect of the leg and, together with

the soleus, forms the triceps surae composite muscle. Alongside the soleus, it serves as the primary plantarflexor of the ankle joint, delivering the propulsive force essential for locomotion. During activities such as running, walking, and jumping, the gastrocnemius contributes significantly to propulsion.

What is the Power Carrier Function of Gastrocnemius?

The gastrocnemius reaches its peak activity during terminal stance, where it flexes the knee and plantarflexes the ankle to help initiate heel lift. In the contact period, it works to decelerate internal rotation of the femur. Its contraction continues through midstance and propulsion phases, supporting subtalar joint supination and external femoral rotation. Additionally, it helps propel the knee forward during the late stage of propulsion.

Soleus

Located beneath the gastrocnemius muscle, the soleus originates from the soleal line on the back of the tibia, the upper third of the fibula's posterior surface, and a fibrous arch connecting these points. As one of the two primary muscles responsible for plantarflexion at the ankle joint, the soleus helps prevent the body from tipping forward during standing, making it essential for posture maintenance.

What is the Power Carrier Function of Soleus?

During terminal stance, the soleus muscle prevents excessive anterior translation of the proximal tibia. Throughout the contact period, it contributes to decelerating tibial internal rotation. The soleus continues to contract during mid-stance and extends into early propulsion, at which point it facilitates supination of the subtalar joint, promotes external rotation of the tibia, and provides stability to the lateral forefoot against the ground.

Peroneals

The peroneal (or fibularis) muscles, consisting of the Peroneus Longus, Peroneus Brevis, and Peroneus Tertius, are located on the outer side of the lower leg. These muscles run along the outside of the shin and pass behind the outer ankle bone. They play key roles in stabilizing the ankle, turning the foot outward (eversion), and pointing the toes downward (plantarflexion). Additionally, they help maintain balance, support the arch of the foot, and prevent ankle sprains. The tendons of these muscles loop beneath the ankle to attach to bones in the foot.

What is the Power Carrier Function of Peroneals?

At midstance, a pronatory force is generated at the subtalar joint, which serves to partially counteract the supinatory forces produced by both the superficial and deep muscles of the posterior compartment. During propulsion, the peroneus longus muscle facilitates plantarflexion of the first ray, while both the peroneus longus and brevis act synergistically to evert the stabilized lateral column. This mechanism effectively redirects body weight medially, thereby enabling a high gear push-off.

In conclusion, efficient locomotion emerges from the seamless integration of force generation, transmission, and control at the foot–ground interface. The five power carriers act as critical modulators, translating large proximal forces into precise, task-specific movements that ensure stability, adaptability, and propulsion. Understanding their coordinated function shifts the focus from isolated muscle strength to system-level performance. Ultimately, appreciating the foot as an active, dynamic structure allows for more informed training, rehabilitation, and performance strategies grounded in how movement truly unfolds.

Antonio Robustelli is the mastermind behind Omniathlete. He is an international high performance consultant and sought-after speaker in the area of Sport Science and Sports Medicine, working all over the world with individual athletes (including participation in the last 5 Olympics) as well as professional teams in soccer, basketball, rugby, baseball since 23 years. Currently serving as Faculty Member and Programme Leader at the National Institute of Sports in India (SAI-NSNIS).