Pins-and-needles or loss of feeling in your feet while running long distances is common. This phenomenon, medically termed paresthesia, can be unsettling. However, foot numbness during running is often temporary and benign. Understanding its causes can help runners address it.
External Factors During Running
Gear worn during a run can influence foot comfort. Improperly fitted shoes can compress nerves and blood vessels, leading to numbness. Adequate toe box space is important, as feet naturally swell during prolonged activity.
The way running shoes are laced also plays a role in potential nerve compression. Tying laces too tightly, particularly across the top of the foot or around the ankle, can create pressure points that restrict circulation and nerve function. Alternative lacing techniques can alleviate this issue.
Socks can also contribute to foot numbness if they are too thick, bunch up, or are made of non-wicking materials. Such conditions increase pressure and friction, potentially compressing nerves. A runner’s form and biomechanics, including foot strike patterns, can also impact pressure distribution. Overstriding, where the heel lands far in front of the body, can increase stress on the foot and prolong ground contact, potentially compressing nerves.
Internal Physiological Causes
Beyond external pressures, the body’s internal responses during sustained running can induce foot numbness. Repetitive impact and muscle swelling can lead to nerve compression, a temporary disruption of nerve signals known as neuropraxia. Specific nerves, such as the common peroneal nerve or those within the tarsal tunnel in the ankle, are susceptible to this compression.
Reduced blood flow, or ischemia, is another physiological contributor. Prolonged pressure or muscle contraction can restrict the supply of oxygen and nutrients to nerve cells in the feet. During intense exercise, the body redistributes blood flow to working muscles, which can sometimes result in temporarily decreased circulation to the extremities, exacerbating numbness.
Muscle swelling within fascial compartments can increase internal pressure, potentially compressing nerves and blood vessels. This exercise-induced compartment syndrome is typically transient. Inadequate hydration and electrolyte imbalances can affect nerve function and muscle contraction, contributing to numbness or cramping. Dehydration can cause blood vessels to constrict and lead to swelling, which can then press on nerves.
While less common for transient numbness in runners, underlying medical conditions can be exacerbated by running. These include peripheral neuropathy (e.g., from diabetes) and sciatica (nerve compression in the lower back). Vascular issues, like peripheral arterial disease, could also manifest as numbness. Such conditions typically present with additional symptoms beyond isolated foot numbness during a run.
Preventative Measures and Solutions
Addressing footwear is a primary step in preventing foot numbness. A professional shoe fitting can ensure proper sizing, adequate toe box space, and an appropriate shoe model for your foot shape and gait. Regularly replacing worn-out shoes helps maintain cushioning and support.
Adjusting lacing techniques can relieve pressure points on the top of the foot. Runners can try skip-lacing, omitting laces over high-pressure areas, or using a “heel-lock” method to secure the heel while allowing more forefoot room. Selecting moisture-wicking, seamless socks of appropriate thickness also reduces friction and pressure.
Maintaining proper hydration and electrolyte balance is important for nerve function and overall circulation. Consuming adequate fluids and electrolytes before and during long runs supports the body’s physiological demands. If numbness persists despite these adjustments, consulting a running coach or physical therapist for a gait analysis can identify and correct biomechanical imbalances or overstriding patterns.
Regular foot care, including stretching and strengthening foot muscles, can improve circulation and nerve health. Incorporating periodic breaks during long runs to wiggle toes, flex feet, or briefly adjust shoe laces can also help alleviate pressure buildup. These combined strategies can significantly reduce the occurrence of foot numbness.
When to Consult a Professional
While often benign, foot numbness during running warrants professional evaluation under certain circumstances. Medical attention is advisable if numbness persists for an extended period after running, or if it occurs even when not engaged in physical activity. Numbness accompanied by severe pain, muscle weakness, changes in skin temperature or color, or noticeable swelling are also red flags.
If the numbness becomes more frequent, increases in severity, or begins to interfere with daily activities beyond running, seeking medical advice is important. Similarly, if the numbness consistently impairs running performance or makes it difficult to continue training, a professional opinion should be sought. Consulting a doctor, sports medicine specialist, podiatrist, or physical therapist can help identify any underlying issues and guide appropriate treatment.