The single-leg stance (SLS) test is a simple clinical assessment tool used by health professionals to gauge an individual’s static balance and postural control. This measure involves timing how long a person can stand unassisted on one foot, serving as a common indicator of overall stability, lower-body strength, and neurological function. Understanding the context and standards for this measurement provides insight into typical balance ability at various life stages.
Age-Based Benchmarks for Standing on One Leg
The time you can maintain a single-leg stance naturally decreases with age, making age-specific benchmarks the most relevant standard for comparison. Inability to achieve a certain time has been linked to an increased risk of falls and overall mortality in older populations.
To perform the test correctly, stand barefoot, lift one foot off the ground, and keep the hands resting on the hips. Timing begins when the foot lifts and stops when the foot touches the ground, the hands move, or the standing foot shifts position.
For younger adults (18–39), the average single-leg stance time with eyes open is approximately 43 seconds. This average remains stable for individuals in their 40s and 50s, who typically maintain the stance for 37 to 40 seconds. The ability to hold the stance declines noticeably after age 60, dropping to 27 to 29 seconds for those in their sixties. Adults in their seventies often average 11 to 18 seconds.
An inability to hold the stance for at least 10 seconds in people over 50 is associated with a higher risk of death from all causes within seven years. For older adults (over 65), an inability to maintain the stance for even five seconds is considered a strong predictor of an injurious fall. These minimum times serve as a practical screening tool for identifying individuals who may benefit from targeted balance and strength interventions.
Physiological Systems Measured by Balance
The single-leg stance test requires the seamless coordination of three distinct physiological systems.
The visual system provides spatial orientation, giving the brain information about the body’s position relative to its surroundings. Maintaining focus on a fixed point offers a constant stream of external reference data that aids in postural control.
The vestibular system is situated within the inner ear and functions as the body’s internal gyroscope. It detects the linear and rotational movements of the head, helping the body sense gravity and maintain an upright posture.
The third system, proprioception, involves sensory receptors located in the muscles, joints, and skin. These receptors constantly relay information about body position and limb location to the central nervous system, allowing for body awareness without visual input and enabling the muscular adjustments required to prevent a fall.
When standing on one leg, the brain must rapidly integrate the input from all three systems to send signals for immediate correction. A poor SLS time can indicate a deficit in one or more of these sensory or motor pathways. Static balance ability has also been linked to cognitive health, as both rely on shared neural pathways. Deficits in balance can sometimes serve as an early indicator of age-related neurological changes or conditions like peripheral neuropathy.
Variables That Affect Test Performance
The result of a single-leg stance test is not solely determined by the underlying health of the balance systems; several external and internal variables can significantly alter the measured time.
The testing surface is a major factor. Standing on a soft surface, such as a thick carpet or cushion, is substantially more challenging than standing on a hard, flat floor. A soft surface reduces reliable sensory input from the foot, forcing the body to rely more heavily on the vestibular and visual systems.
Footwear also influences performance, which is why testing is typically performed barefoot to maximize sensory feedback from the sole of the foot. Certain medications that cause drowsiness or dizziness can temporarily impair the nervous system’s ability to process balance information, leading to a reduced stance time. Temporary states like fatigue, illness, or recent strenuous exercise can similarly reduce muscle coordination and reaction speed.
The use of vision is another variable that dramatically affects the time an individual can maintain the stance. When the test is performed with eyes closed, the visual system is eliminated, forcing the body to rely entirely on proprioception and the vestibular system. The average time for a single-leg stance with eyes closed is often less than a quarter of the eyes-open time, highlighting the significant role of vision in static balance.
Practical Methods for Improving Your Stance
Improving single-leg stance time requires consistent practice that progressively challenges the body’s balance systems. A simple starting point is to integrate practice into daily routines, such as standing on one leg while brushing your teeth or waiting in line. This allows for focused practice without requiring dedicated time, making consistency easier to maintain. Always begin by standing near a stable object, like a counter or wall, for support if needed.
Once you can comfortably maintain a single-leg stance for 30 seconds with your eyes open, increase the challenge. A common progression is to remove visual input by closing your eyes, forcing the proprioceptive and vestibular systems to work harder. You can also introduce controlled head movements, such as slowly nodding or shaking your head, to specifically challenge the vestibular system while standing on one leg.
To further enhance proprioception and ankle stability, try standing on a less stable surface, such as a folded towel or a balance pad. Combining these challenges, such as standing on a cushion with eyes closed, should only be attempted once simpler variations are mastered for safety. Consistent training, even for a few minutes daily, can significantly improve balance, strengthen the hip and core muscles, and improve overall functional stability.