Exercise for foot strength to improve running and sports performance

The foot and ankle complex is the link in the chain that expresses the forces generated by the lower limb through the floor for locomotion during walking, running or sprinting. Already touted by previous professionals and coaches, the foot provides an opportunity for performance enhancement on the field if trained in a way that improves its absorption and expression qualities needed for running and change of direction movements.

Below are my thoughts on training the foot-ankle complex and what exercise for foot strength we can use to improve sports performance.

The ankle-joint complex and the three rockers

The ankle complex is formed by the articulations of the talocrural, distal tibiofibular, and subtalar joints and during gait, the foot and leg move around 3 axes of rotations which are called rockers (McKeon et al., 2019). They are the heel, ankle and forefoot rocker (McKeon et al., 2019).

Figure 1 taken from McKeon et al., 2019. A represents the heel rocker. B is the ankle rocker. C is the forefoot rocker.

Once heel strike occurs and the foot is lowered to the ground, rotation occurs around the feel and the is referred to as the heel rocker. During stance phase with the foot flat on the ground, the shank moves forward over the foot rotating about the talocrural joint, this is the ankle rocker. The penultimate phase is moving into terminal stance where the heel and mid foot lift off and rotation occurs about the metatarsophalangeal joints; this is known as the forefoot rocker.

Computational modelling for the three-foot rocker mechanisms during the gait cycle estimate that the heel, ankle and forefoot rocker occur through 0-10%, 10-50% and 50-60% of stance phase respectively (Yanguma-Muñoz et al., 2024). The authors model estimates that forces equivalent to one time body weight and three times bodyweight occur during the ankle and forefoot rocker respectively. It is worth noting that the same model showed increased pressure during the ankle to forefoot rocker on the medial border of the plantar foot surface and during the final phase of the forefoot rocker, the lateral two toes loose contact with the ground, emphasising the weight shift through the 1^st metatarsophalangeal joint and the medial two toes. 

We could suggest that the ankle rocker is a transitional movement – akin to the amortization phase between an eccentric and concentric contact i.e. moving from absorption to propulsion (McKeon et al., 2019) and the individual’s centre of gravity advances over the stance foot. As the modelling paper by Yanguma-Muñoz et al. highlights there is a greater pressure on the medial border and longitudinal arch and as a transition movement, we need high amounts of stiffness to maintain energy transfer with minimal leaks! 

Role of the intrinsic and extrinsic foot and ankle muscles and the importance of stiffness during running and change of direction

We are not going to go into detail around the anatomy of the foot-ankle complex, for a great read please refer to Chan & Rudins (1994) and Rodgers (1995) – we will focus on the applied anatomy needed for the context of this post.

There are two combined movements we need to define first.

As stated by Chan & Rudins (1994) pronation of the foot is the result of combined eversion, abduction and dorsiflexion and supination of the foot is the combined result of inversion, adduction and plantarflexion of the foot-ankle complex.

During the ankle and forefoot rocker the tibialis posterior functions to help maintain rear foot in a locked position. EMG studies, although few is number and with small sample sizes (n=15) appear to show that the TP muscle fires in short bursts during the ankle and forefoot rocker (Semple et al., 2009). Both the tibialis posterior and peroneus longus appear to show a sudden and sharp burst to peak activation (we should understand EMG amplitude has rather substantial limitations when extrapolating to muscle activation see Vitsgosky and Lehman, 2019, link paper) around 80% of stance phase during running (O’Connor et al., 2006) before then a rapid decline. This likely corresponds to the later stage of the ankle rocker and most certainly the forefoot rocker – during the latter rocker both muscles (along with the other invertors and evertors) serve to maintain stiffness in the medial-lateral direction and minimise energy leaks through the frontal plane.

The phasic nature of the patterns of activation of both the invertors and evertors suggest rapid rate force development sustained for short periods of time.

Once the plantar foot is on the ground (ankle rocker) and transition through the propulsion in the forefoot rocker phase, the four layers of intrinsic food muscles function to maintain stiffness of the longitudinal and transverse arch of the foot by shortening the distance between the metatarsal heads and calcaneus (McKeon et al., 2019). Again, the emphasis on stiffness ensures minimal energy leaks during high-speed running and change of direction and is highlighted by Tourillon et al., who found foot-ankle reactive strength accounted for 28% and 35% of vertical impulse and ground contact time during maximal running speed in a group of 52 athletes, and 14% of negative work (absorption) during change of direction, with it being highlighted that greater forefoot strength and foot passive stiffness was imperative to performance in this sample (Tourillon et al., 2024).

The importance of the first metatarsal phalangeal joint in the final phase of propulsion to minimise energy leaks.

Riley et al., (2013) observed foot kinematics of professional American Football players during both short acceleration drills and change of direction activities (involving cut step, 180-degree plant step and lateral shuffle) performed with maximum intent show similar spatiotemporal patterns in the 1^st MTPJ joint.

They found dorsiflexion of the joint begins as early as 25% of stance phase and peaks between 80-90% of stance phase. Regarding peak forces, it was reported that they reached 100%- and 200%-times bodyweight through the medial and vertical orientation of the foot respectively, and this peak occurred somewhere between 65-75% of stance phase.

The importance of 1^st MTPJ function is highlighted in several studies investigating the relationship to sports performance. Yuasa et al., (2018) investigated MTPJ strength in neutral and at 45 degrees and found that in collegiate American Football players (n=17) greater force produced by the MTPJ in 45 degrees of dorsiflexion was inversely associated with time to complete the 3-cone and pro agility test (r = −0.498 and −0.503, small correlation).

Toe strengthening (of the flexors) performed for 7 weeks at 90% maximal voluntary isometric contraction (MVIC) resulted in a 6cm increase in broad jump scores in resistance-trained men (n=15) with no other training performed during this period (Goldmann et al., 2013). Broad jump requires increased horizontal expression of force compared to a countermovement or drop jump and taken with the findings of Yuasa et al., above, MTPJ force is likely a critical factor during change of direction and acceleration tasks where the athlete is adopting positions that require large amounts of force generation in the horizontal axis thus a resultant force vector is more horizonal and force expression in the foot will correspond with increased MTPJ dorsiflexion during propulsion.

During such a position, high amounts of both horizontal and vertical forces would be needed to propel the athlete forward and it is no surprise then that Tourillon et al., found toe flexor strength measured at 30 degree dorsiflexion accounted for 27% and 36% of vertical impulse and ground contact time in 52 high-level athletes during maximal acceleration, 90-degree cut and jumping activities (Tourillon et al., 2024).

Why a stiff, reactive foot is imperative to sprint and change of direction performance.

Ground contact time during sprinting of elite 100-metre runners is as low as 0.11 seconds (Blauberger et al., 2021) and during change of direction movements like the diagonal cut and plant step is in the region of 0.3-0.44 seconds (Riley et al., 2013).

This means that we have less than 0.5 seconds to from contact to toe off to absorb and express high amounts of force, which in the foot can be up to two times the athlete’s bodyweight. Looking at factors influencing sprint performance, horizontal rate force development throughout the entire acceleration phase and vertical and braking RFD during the later phase of acceleration moderately correlate with sprint performance (time) (Nagahara et al., 2025) and larger amounts of propulsive impulse and vertical force enable greater rates of acceleration and maintenance of maximal running speed respectively in elite sprinters during a maximal 60-metre sprint (Nagahara et al., 2018).

The papers above highlight two important variable to consider. Both large amounts (magnitude) of force and the rate at which we can produce it are strong determinants of acceleration and top end speed. Thinking about our game athletes, most will not be in situations where they need top end speed, but all will be in situations where they need acceleration qualities. Whether that be short 20 metre sprints to break the line on the wing, charge into open space to break up the opponent’s line or accelerate after performing a lateral cut step around an opponent. Every movement involves an acceleration of some sort.

Thus, a stiff foot that can absorb and express high amounts of force very quickly means less energy leaks from the system and ultimately, more is transferred into propulsion in the direction of choice. The athlete with a foot that is either weak and slow or has high peak force capacity but cannot produce it quick enough, will likely find their performance increases following a shift in focus on RFD foot-ankle complex training as there are less energy leaks through the final stage of the kinetic chain.

Consequently, exercise for foot strength targeting the foot-ankle complex should focus on a mixture of peak force and rate of force development.

Training the foot the improve running performance.

Although the work done by the foot happens within 500ms of ground contact time or less, peak force is still important to consider within a block of training. Why? Because when we increase the max force capacity, there is tendency to increase the subceiling at which we can produce force very quickly across different submaximal loads. In more simple terms using the figure below, training with loads close to the 1RM shifts the force-velocity curve to the right ultimately increasing the velocity for all loads with weight held constant (Moss et al., 1997; Østerås et al., 2022).

This is shows the shift in capacity to produce both higher peak force and higher force at higher velocities following training.

Isometric exercise is a focal aspect of exercise for foot strength. This is because of both its utility for eliciting joint angle specific adaptions and specificity to sporting demands. The final phase of the forefoot rocker results in first MTPJ dorsiflexion of 30-45 degrees. Thus, training this angle will likely yield highly specific adaptions to that position during change of direction or acceleration tasks. Isometric exercise appears to show the greatest increases in force relative to the angle trained with decreasing adaptions the further away from it (Oranchuk et al., 2019). Although, this diminishing return at angles further from that which was trained does not appear to be as pronounced when isometric exercise is performed at long versus shorter muscle lengths (Oranchuk et al., 2019). As I mentioned at the beginning, Cal Dietz has already done a great job of the forefoot rocker isometric progressions.

Oranchuk et al., highlights the specificity of contraction style on adaptations. Ballistic isometric exercise increases rate of force development during the first 0-250 milliseconds of maximal isometric contraction. Revisiting the burst-phasic nature of the tibialis posterior and evertors during the heel-ankle-foot rocker motion previously discussed, repeated ballistic isometric exercises like those in the video below, targeting the two muscle groups would replicate the demands of both high-rate force development and the cyclical nature during gait.

Even for the foot intrinsics and toe flexors, ballistic isometrics and ballistic exercises to supplement long slow isometric holds could be used as part of a block of training for athletic foot development – remember we only have up to 500 milliseconds of ground contact time to produce force. The specificity of training would emphasise that some focus given to ballistic action would be sensible.

Below is the video on my YouTube channel detailing all exercise progressions.

Video 2: Insert video for ballistic slack rope / isometrics for evertors / invertors / foot muscles 

Putting it into a block of training

It would make sense to start with a block dedicated to maximal force production. We should increase the height of the force ceiling before we try and increase the rate at which we try to reach it.

This need only last 4-6 weeks if we are training the foot 2-3 x weekly with the exercises above. For the Forefoot rocker 1 and 2 exercise, 2 sets of 10 seconds building to 30 seconds before adding external resistance is more than enough volume to drive adaptations. Watch the video for how you can progress intensity.

The ballistic isometrics or exercises use volumes around 10-15 sets for 1-2 second bursts, the emphasis on the execution is maximal intent as quickly as possible. If you want a more extensive focus on rate of force i.e. capacity to continually produce force quickly under fatigued conditions, then you could use a timer and go for 30 – 60 seconds and perform as many as possible before you reach fatigue and the ability to maintain stiffness drops off. As previously mentioned, before starting ballistic isometrics and exercises I would focus a dedicate block to building maximal strength. This really lays the foundation to get the most out of subsequent exercises that really focus on high RFD. Once you can go through 2 – 3 block cycles, there is no reason why you could not undulate the two across a week with the high intensity at the beginning and the RFD toward the end of the week.

Hopefully this post highlights some of the nuances and challenges to training the foot-ankle complex for on field performance and how to go about doing it! Drop any comments in the section below or get in touch on social media.

References

McKeon, J. M. M., & Hoch, M. C. (2019). The ankle-joint complex: a kinesiologic approach to lateral ankle sprains. Journal of athletic training, 54(6), 589-602.

Yanguma-Muñoz, N., Bayod, J., & Cifuentes-De la Portilla, C. (2024). A single computational model to simulate the three foot-rocker mechanisms of the gait cycle. Scientific Reports, 14(1), 29051.

Chan, C. W., & Rudins, A. (1994, May). Foot biomechanics during walking and running. In Mayo Clinic Proceedings (Vol. 69, No. 5, pp. 448-461). Elsevier.

Rodgers, M. M. (1995). Dynamic foot biomechanics. Journal of Orthopaedic & Sports Physical Therapy, 21(6), 306-316.

Semple, R., Murley, G. S., Woodburn, J., & Turner, D. E. (2009). Tibialis posterior in health and disease: a review of structure and function with specific reference to electromyographic studies. Journal of foot and ankle research, 2(1), 24.

O’Connor, K. M., Price, T. B., & Hamill, J. (2006). Examination of extrinsic foot muscles during running using mfMRI and EMG. Journal of Electromyography and Kinesiology, 16(5), 522-530.

Riley, P. O., Kent, R. W., Dierks, T. A., Lievers, W. B., Frimenko, R. E., & Crandall, J. R. (2013). Foot kinematics and loading of professional athletes in American football-specific tasks. Gait & posture, 38(4), 563-569.

Goldmann, J. P., Sanno, M., Willwacher, S., Heinrich, K., & Brüggemann, G. P. (2013). The potential of toe flexor muscles to enhance performance. Journal of sports sciences, 31(4), 424-433.

Tourillon, R., Michel, A., Fourchet, F., Edouard, P., & Morin, J. B. (2024). Human foot muscle strength and its association with sprint acceleration, cutting and jumping performance, and kinetics in high-level athletes. Journal of Sports Sciences, 42(9), 814-824.

Blauberger, P., Horsch, A., & Lames, M. (2021). Detection of ground contact times with inertial sensors in elite 100-m sprints under competitive field conditions. Sensors, 21(21), 7331.

Nagahara, R., Girard, O., & Messou, P. A. (2025). Rates of ground reaction force development are associated with running speed during sprint acceleration. International Journal of Sports Science & Coaching, 20(1), 123-129.

Nagahara, R., Mizutani, M., Matsuo, A., Kanehisa, H., & Fukunaga, T. (2018). Association of sprint performance with ground reaction forces during acceleration and maximal speed phases in a single sprint. Journal of applied biomechanics, 34(2), 104-110.

Moss, B. M., Refsnes, P. E., Abildgaard, A., Nicolaysen, K., & Jensen, J. (1997). Effects of maximal effort strength training with different loads on dynamic strength, cross-sectional area, load-power and load-velocity relationships. European journal of applied physiology and occupational physiology, 75(3), 193-199.

Østerås, H., Helgerud, J., & Hoff, J. (2002). Maximal strength-training effects on force-velocity and force-power relationships explain increases in aerobic performance in humans. European journal of applied physiology, 88(3), 255-263.

Oranchuk, D. J., Storey, A. G., Nelson, A. R., & Cronin, J. B. (2019). Isometric training and long‐term adaptations: Effects of muscle length, intensity, and intent: A systematic review. Scandinavian journal of medicine & science in sports, 29(4), 484-503.