The human body contains somewhere between 250 and 350 joints. We are made for movement.
Getting the most out of movement means getting the most out of our joints, making a full range of motion central to healthy, functional movement. In addition to balanced strength and flexibility, as well as efficient neuromuscular control of movement, our ability to articulate and control movement across our joints’ full range of motion increases our ability to move freely, easily, and without injury and not only when it comes to the more athletic movements of exercise or sports. Getting up from a chair, bending down to pick up a bag of groceries, walking to the coffee shop around the corner—all these everyday actions also require a complete and functional range of motion.
What Is Range of Motion?
Though it is often used interchangeably with flexibility, range of motion refers to the distance a joint can move, as well as the directions in which it can move. Flexibility refers to the ability of soft tissue structures like muscles, tendons, and connective tissue to elongate, and while this can impact a range of motion, it is distinct from it. A joint is considered to have a full range of motion when it can easily traverse the entire range of anatomically possible movements at that joint.
Range of motion can be passive or active, varying widely across these two distinctions. Passive range of motion refers to the movement possible at a joint when someone else is moving our body around that joint, as might occur in assisted stretching or a physical therapy session. When we articulate our joints ourselves without any assistance, this is considered an active range of motion. Therapeutic and rehabilitative exercises may also include an active-assisted range of motion activities, when a joint receives partial assistance from another person or outside force.
While muscle stiffness and pain are common culprits for limited range of motion, the movement possible at a joint can also be impacted by soft tissue inflammation, injuries like dislocations and fractures, and other medical conditions, such as arthritis, cerebral palsy, and sepsis.
Range of Motion in Walking
While it might seem simple, walking is a beautifully complex action involving the entire body. To understand the relationship between walking and range of motion more deeply, it’s helpful to break down our gait cycle, or the sequence of events that occur from the time one heel strikes the ground to the time that same foot returns for its next step.
There are two phases to the gait cycle: the stance phase and the swing phase. The stance phase is when one leg and foot support most or all our weight, accounting for up to 60% of the cycle. The swing phase, when the non-weight-bearing foot passes the other leg without touching the walking surface, accounts for an additional 40%. These two phases can be further divided into eight subphases, starting with “initial contact” (when the heel strikes the ground) and ending with “late swing,” the period of deceleration before the next heel strike.
Each of the eight subphases of walking requires the major joints of the lower body—hips, knees, and ankles—to move through varying degrees of flexion (bringing our body parts closer together) and extension (elongating our body parts away from each other). In a normal gait, the hip joint moves through up to 30 degrees of flexion and 10 degrees of hyperextension, the knee moves between 0 (or completely straight) and 60 degrees of flexion, and the ankle moves through 5 degrees of dorsiflexion to 20 degrees of plantar flexion (flexing and pointing the foot, respectively). The bones of the feet, specifically the metatarsophalangeal joints (or toe joints), also move through flexion and extension over the course of our walk.
Effects of Limited Range of Motion in Walking
A restricted range of motion in any part of our body can lead to pain, discomfort, improper alignment, increased muscular tension, and ultimately dysfunctional compensatory patterns elsewhere. The quality of our walk can also suffer from limited range of motion. And because we walk so frequently, limited range of motion may go relatively unnoticed unless we choose to investigate our walk more closely.
More specifically, studies have found that a constrained range of motion at the knee joint can negatively impact the coordination of the lower and upper leg bones of the affected leg in walking, as well as the coordination and timing of stance and swing phases. Reduced knee flexion in walking can also lead to increased, compensatory movements and muscular activations at the hip and ankle joints, in addition to shorter pre-swing subphases and longer swing durations. In short, the recruitment of muscles as well as the coordination of walking is affected by reduced range of motion at the knee.
It isn’t only muscular activity and coordination that are affected by a poor range of motion. Another study found that a limited range of motion in the lower body also increases variability in coordination, meaning that the organization of movement is inconsistent from step to step.
Of course, walking involves more than just our lower body. A crucial aspect of our two-legged gait is the contralateral swinging of our arms. This oppositional arm-leg movement helps balance the rotational motion produced by walking. While people can walk without swinging their arms, studies have shown that a proper arm swing can improve stability and maximize energy efficiency. Thus, a limited range of motion in the joints of the upper body can also impact your walk. In fact, one study found that limited flexion of the elbow in walking corresponded with slower walking, decreased stride length, and increased single-leg stance and double support times, which can indicate poor balance.
Improving Range of Motion
There are a variety of techniques and methods physical therapists and other experts recommend for increasing range of motion.
Dynamic and Static Stretching
When most people think of stretching, they think of static stretching—holding a position in which muscle tissue is elongated—but this is not the only way to lengthen soft tissue structures and improve range of motion. In dynamic stretching, you move in and out of your available range of motion. Dynamic stretching is most effective as a warm-up, and static stretching is most effective at the end of physical activity. In both, it’s important never to stretch to the point of pain or to hold stretches for too long. The best approach is to consult with a professional, as both types of stretching can be more or less effective (and occasionally actively detrimental) depending on your personal goals.
Foam Rolling
Research is still underway on the effectiveness of using a foam roller to put pressure on, and stimulate your muscles. Initial results suggest that self care with these cylindrical tubes of compressed foam can help improve joint range of motion without some of the safety concerns of other activities, like static stretching. By releasing your body’s myofascial tissue, foam rolling can alleviate not only muscle tightness but also soreness, stress, and tension more broadly.
Neuromobilization
Neuromobilization, or nerve gliding, is also still under investigation as a means of improving range of motion. Like foam rolling, initial results suggest that it can be beneficial. When healthy, our nerves are covered in a very flexible protective sheath. When irritated or damaged, this sheath loses its flexibility and can lead to pain and reduced range of motion. Nerve gliding involves a series of exercises that gently stretch the irritated nerve and restore the sheath’s flexibility.
Walk Freely with Full Range of Motion
The next time you’re out on a stroll, check in with your walk to feel out your range of motion and whether you have any restrictions. New products with cutting-edge gait analysis technology, such as that found in Baliston shoes, measure your walking from a joint mobility and health perspective through your stride length and the angles of the foot as your foot comes off the ground. Baliston's Joint Mobility Score helps provide insights into your body to help reduce joint pain and prevent injury.
So whether you’re on a busy city sidewalk or a remote backcountry trail, a single step is a dynamic portrait of a complex neuromuscular activity millions of years in the making. From our oldest bipedal ancestors to now, a healthy gait depends on more than strength, flexibility, and alignment—it requires full and functional range of motion. By using some of the techniques described above to improve your flexibility, and using modern technology to better understand your biomechanics, you’ll be able to get the most out of your joints, move more, and move better.