Join the news democracyWhere your votes decide the Top 100
So, how long can you stand on one leg?
Scientists believe that the answer to that question is a strong indicator of how susceptible someone is to suffering a stroke.
Researchers from the University of Tokyo asked more than 1,300 men and women, with an average age of 67, to stand on one leg with their eyes open.
They found that those who struggled to balance for 20 seconds or longer (around a third of the study group) fared the worst on tests assessing cognitive function.
There was also an increased prevalence among this group of cerebral small vessel disease or minute haemorrhages associated with a higher risk of strokes.
Study lead Yasuharu Tabara wrote: "One-leg standing time is a simple measure of postural instability and might be a consequence of the presence of brain abnormalities."
Source: American Heart Association / Kyoto University