Human Locomotion

Successful 10-second one-legged stance performance predicts survival in middle-aged and older individuals. Araujo C, et al. Br J Sports Med 2021.

Monthly Research Articles

In this study, 1702 individuals between the ages of 51 and 75 were followed for 12 years. At the start of the study, subjects were asked to stand on one leg and balance with their eyes open for 10 seconds. To ensure consistency, subjects were told to keep their arms at their sides with their elbows straight and to fix their gaze on an eye-level point that was 6 feet away. To reduce compensatory movements, they were told to place the top of the non-support foot on the back of the opposite lower leg “as naturally as possible” (Fig. 1). Once they assumed this position, they were given three chances to complete a 10-second single-leg balance test. They were classified as either “Yes” or “No” depending upon their ability to complete the test. 

Overall, 20% of individuals were classified as No, and the survival curves for these individuals was significantly worse. During a mean follow-up of seven years, 7.2% of the subjects died with 4.6% of them being in the yes group, and 17.5% being in the no group. The authors note that the hazard ratio of all-cause mortality was higher for the No individuals even after adjusting for age, sex, body mass index, and other comorbidities. The authors state that “unlike aerobic fitness, muscle strength, flexibility, balance tends to be reasonably preserved until the sixth decade of life, when comparatively, it starts to diminish quickly.” This is consistent with prior research showing that toe strength is a better predictor of longevity then grip strength, and strength training enhances balance more than balance exercises. This simple test should be a standard component of a biomechanical examination and interventions to improve balance, including proprioceptive and strengthening exercises, should be incorporated immediately, and the importance of improving balance should be conveyed to the patient.