The heel strike is the most common and natural pattern of initial ground contact when walking. It marks the moment the heel first meets the ground as the body prepares to bear weight. This contact initiates a complex sequence of movements that allows for forward motion. While heel striking is universal, its biomechanical implications are frequently misunderstood, leading to questions about its effect on the body. This initial touch sets the stage for how forces are absorbed and distributed through the skeletal system.
Understanding the Gait Cycle
Walking is a cyclical motion known as the gait cycle, which begins when one foot touches the ground and ends when the same foot touches the ground again. The process is divided into the stance phase, when the foot is on the ground, and the swing phase, when the foot moves forward through the air. Heel strike is the first moment of the stance phase, specifically called the Initial Contact sub-phase, which then transitions into the Loading Response.
The heel strike is one of three primary foot strike patterns, which also include midfoot and forefoot strikes. Landing heel-first initiates the “rocker” mechanism, where the foot rolls forward from the heel, along the outside edge, to the ball and toes. This rolling action is designed to maintain momentum and is highly efficient for prolonged walking. The stance phase, which starts with the heel strike, typically accounts for about 60% of the entire walking cycle.
How Heel Strike Impacts the Body
The moment the heel contacts the ground, it generates a measurable force called the Ground Reaction Force (GRF). Immediately following contact, a spike in the vertical GRF, known as the impact transient, occurs as the body rapidly decelerates the limb. This impact transient can be a sharp, high-frequency force peak, reaching up to 100% or more of body weight in barefoot walking.
This impact force must be managed by the body’s shock-absorption mechanisms, which include the ankle, knee, and hip joints, as well as the surrounding musculature. If the foot lands too far in front of the body’s center of mass, a condition known as overstriding, the impact forces increase significantly. Overstriding exaggerates the braking force—the horizontal force that opposes forward motion—making the gait less efficient and sending a greater shockwave up the kinetic chain.
The forces associated with an aggressive heel strike travel upward, potentially placing increased stress on the joints. The knee is particularly involved in absorbing this impact, often undergoing a small, controlled “flexion wave” to mitigate the shock. While the heel strike is natural for walking, excessive force transmission can put undue strain on the lower back, hips, and knees over time. However, for most people walking at a normal pace, the body’s natural cushioning and muscle control effectively manage these forces.
Assessing and Adjusting Your Foot Strike
You can gain insight into your foot strike pattern by examining the wear on the soles of your walking shoes. A typical heel striker will show the most wear on the back-outside edge of the heel, reflecting the initial point of contact. Another simple method is to listen to your footfalls; a loud, heavy, or “slapping” sound upon contact may suggest an aggressive heel strike.
Modifying a walking heel strike is generally not necessary unless you experience chronic pain in the feet, knees, or hips that is directly linked to your gait. The most effective adjustment is to focus on reducing overstriding, which is accomplished by simply shortening your stride length. Rather than reaching out with the foot, aim to land the foot closer to directly underneath your hips.
A practical technique involves slightly increasing your cadence, or steps per minute, which naturally shortens your stride and reduces impact forces. When selecting footwear, look for walking shoes that allow the forefoot to flex easily. Avoid shoes that have an excessively flared or thick heel, as this can worsen overstriding. These minor changes are usually sufficient for optimizing walking mechanics.