What Balancing On One Leg Reveals About Your Brain
The length of time you can balance on one leg reveals some important information about your brain health, according to a new study from Japan. In addition, previous research has indicated an association between balance ability and brain function.
The first thing I did when I read the findings of the study was to stand on one leg and see how long I could balance. Fortunately, I bypassed the 20 second mark with flying colors, which is the value assigned by the authors of the study as the low end of the scale.
Balancing on one leg: new study
According to the investigators, otherwise healthy adults who cannot balance on one leg for at least 20 seconds could be at higher risk for brain problems in the form of small blood vessel damage and asymptomatic cerebral small-vessel disease, which is a risk factor for stroke. The reasoning is that compromise of the small vessels makes the arteries less flexible, which in turn interferes with blood flow. Thus there is a relationship between less efficient circulation in the brain and legs.
Here’s what the researchers did in the study.
- A total of 1,387 older (average age, 67) men and women were asked to balance on one leg for up to 1 minute (if possible) while they kept their eyes open. All the participants tried this balancing test twice.
- The investigators then examined the brain of each participant using magnetic resonance imaging (MRI) and noted any damage to the cerebral small blood vessels.
- Each participant also completed a questionnaire designed to evaluate their cognitive function
Here’s what the authors discovered:
- There was an association between the presence of subclinical infarctions (blockage of blood vessels leading to the death of tissue) and an inability to balance on one leg for more than 20 seconds. Subclinical infarctions include microbleeds and lacunar infarctions. The former are minute chronic hemorrhages that are mostly caused by structural abnormalities in small blood vessels in the brain while the latter are “small (0.2 to 15 mm in diameter) noncortical infarcts caused by occlusion of a single penetrating branch of a large cerebral artery.”
- Slightly more than half of the participants who had difficulty balancing on one leg for 20 seconds had at least one lacunar infarction lesion and nearly half had at least one microbleed lesion
- The inability to balance on one leg for more than 20 seconds also was independently associated with lower scores on the cognitive functioning questionnaire
According to the study’s lead author, Yasuharu Tabara, from Kyoto University Graduate School of Medicine, men and women who show poor balance while standing on one leg “should receive increased attention, as this may indicate an increased risk for brain disease and cognitive decline.”
Balancing on one leg: previous research
In another recently published study, investigators looked at the ability to balance (on one leg with eyes closed for up to 30 seconds), grip strength, and chair rising speed in 2,766 adults at age 53 and then again 13 years later (age 66). The authors found that:
- Participants who were unable to perform any of the tests had much higher rates of death from all causes (e.g., cancer, cardiovascular disease, other causes) when compared with their peers who could do all three tests
- The findings suggested that a shorter standing balance time was more strongly associated with dying than the other two factors.
An inability to stand on one leg and balance for 20 seconds or more does not necessarily mean you have a problem with your brain health. Use of some medications, ear infections, low blood pressure, and numerous factors can cause people to have difficulty maintaining their balance.
However, researchers have gathered evidence that an ability to balance on one leg for a specified amount of time may be an indication that there is an issue with brain health, including the risk for stroke. Clinicians may want to use this simple test when evaluating their patients.
Cooper R et al. Physical capability in mid-life and survival over 13 years of follow-up: British birth cohort study. BMJ 2014; 384:g2219
Martinez-Ramirez S et al. Cerebral microbleeds: overview and implications in cognitive impairment. Alzheimer’s Research & Therapy 2014; 6:33
Tabara Y et al. Association of postural instability with asymptomatic cerebrovascular damage and cognitive decline. Stroke 2014 Dec 18 online