Does Toe Strength Help You Jump? Four Trials Say Yes — Sideways

Most of what this site says about toe strength and performance is negative. It does not improve running economy. It does not correlate with sprint speed. We have said so, with the studies attached, because that is what the studies found. Jumping is different, and it is worth being precise about how.

The association

Start with the cross-sectional picture. In young adults, toe flexor strength — measured on a grip dynamometer, toes pressing down — correlated with vertical jump height, peak power and reactive strength, and with the vertical impulse applied to the ground. Arch height, measured in the same people, did not.¹ The same association holds in adolescents.²

Association is not cause. People with strong toes may simply be people with strong legs. So the question is what happens when you train the toes and nothing else.

The trials

Four intervention studies have done that, over six to eight weeks, in healthy young adults.

Goldmann 2013. Fifteen men, seven weeks of heavy toe flexor training at 90% of maximal contraction — 560 contractions per foot. Toe flexor strength rose by more than half. Standing long jump improved. Vertical jump, walking and running did not change.³

Unger & Wooden 2000. Six weeks of toe flexor strengthening in physically active adults. Both vertical and horizontal jump improved.⁴

Hashimoto & Sakuraba 2014. Twelve men, eight weeks. Horizontal jump improved; vertical jump did not.⁵

Kokkonen 1988. The earliest of the four. Horizontal jump improved.⁴

A 2025 analysis that reviewed all four put it plainly: every study found an improvement in horizontal jump, and the gains did not consistently translate into vertical jump.⁶ Four for four sideways. Roughly one in four straight up.

Why sideways

Goldmann's group offered a mechanical explanation that fits the rest of the evidence on this site. In a standing long jump, the toe joints are bent upward — dorsiflexed — as you drive off, and large moments of force run through them. Stronger toe flexors working in that position do more. In a vertical jump the toes contribute less and the calf and thigh do almost all of it.³

This is the same finding, from a different angle, as the one in our soccer article: toe push-off strength with the joints dorsiflexed correlated with change-of-direction ability, and not with straight-line sprinting. The toes matter when the foot is loaded at an angle. Straight up and straight ahead, they matter less.

What this means by sport

• Volleyball and basketball. The vertical jump is the headline skill and the evidence there is mixed. The lateral shuffle, the cut, the block-and-recover — those are angled push-offs, and that is where the consistent effect lives. If you train your toes for these sports, expect the benefit in your first step, not your reach.
• Long jump, triple jump, broad-jump testing. The one place the trials agree.
• Dance. A randomised trial of toe flexor training in adolescent ballet dancers, measuring strength and both jump types, was published in 2026.⁷ It is the first in dancers. We have not yet read its full results — see the note below — and until we have, we will not characterise them.

What the trials did not test

The training in these studies was heavy. Goldmann's subjects worked at 90% of maximum on a dynamometer. Toe-Rx offers the resistance of foam. Whether closing the toes against a foam separator, fifteen to twenty times every other day, loads the toe flexors enough to produce the gains measured with dynamometer-level training has not been tested, and we are not going to assume it. What the separator does that a dynamometer does not is hold the toes apart first — abduction held, flexion worked — which none of these four trials involved.

Two further trials on big-toe strength training and athletic performance are registered and recruiting.⁸ The picture will sharpen.

Where Toe-Rx fits

It is the tool for the closing movement, and the evidence above is the best case for that movement mattering to performance — horizontal, angled, off the line. It is not a case for vertical jump, and we will not make it one. After a session, seated, ten minutes, every other day. Never before: a long static hold in the minutes before explosive work is the one timing the evidence argues against.⁹ How to use it is here.

*These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.

References

1. Yamauchi J, Koyama K. Importance of toe flexor strength in vertical jump performance. Journal of Biomechanics. 2020;104:109719. doi:10.1016/j.jbiomech.2020.109719. PMID: 32173032.
   Cross-sectional. The original volleyball post cited this to the wrong journal.
2. Kurihara T, Terada M, Numasawa S, Kusagawa Y, Maeo S, Kanehisa H, Isaka T. Effects of age and sex on association between toe muscular strength and vertical jump performance in adolescent populations. PLOS ONE. 2021;16(12):e0262100. doi:10.1371/journal.pone.0262100. PMID: 34972181. Read it
3. Goldmann JP, Sanno M, Willwacher S, Heinrich K, Brüggemann GP. The potential of toe flexor muscles to enhance performance. Journal of Sports Sciences. 2013;31(4):424–433. doi:10.1080/02640414.2012.736627. PMID: 23106289. Read it
   15 men, 7 weeks, 90% MVIC. Horizontal jump improved; vertical jump, walking and running unchanged.
4. Unger CL, Wooden MJ. Effect of foot intrinsic muscle strength training on jump performance. Journal of Strength and Conditioning Research. 2000;14(4):373–378.
   CONFIRM BEFORE PUBLISHING — cited via Taddei et al. 2020 (Phys Ther Sport) and the 2025 review. Kokkonen et al. 1988 is cited the same way and its full citation was not captured.
5. Hashimoto T, Sakuraba K. Strength training for the intrinsic flexor muscles of the foot: effects on muscle strength, the foot arch, and dynamic parameters before and after the training. Journal of Physical Therapy Science. 2014;26(3):373–376. PMID: 24707086.
6. Human foot muscle strength and its association with sprint acceleration, cutting and jumping performance, and kinetics in high-level athletes. 2025.
   CITATION INCOMPLETE — the source of the "all four improved horizontal jump, not consistently vertical" synthesis. Locate the published version and complete before publishing.
7. Schrefl A, Schärli A, Goldmann JP, Erlacher D, Kolokythas N. The effect of targeted toe flexor training on muscular strength and jump performance in adolescent ballet dancers: a randomized controlled trial. Journal of Dance Medicine & Science. 2026. doi:10.1177/1089313X261420458.
   RESULTS NOT YET READ — see notes. Adolescent participants.
8. ClinicalTrials.gov NCT06197932 and NCT06986681. Big toe strength training and athletic performance parameters.
   Registered trials, not results.
9. Revisiting the stretch-induced force deficit: a systematic review with multilevel meta-analysis of acute effects. Journal of Sport and Health Science, 2024. Read it