Simone Biles graced the balance beam in the 2019 World Championships and took the gold — without a single wobble. But for mere mortals, just getting through a 10-second, one-leg balance test can be a major challenge.

That's the conclusion of a study published in the British Journal of Sports Medicine. The researchers found that 20% of the 1,700 older adults they tested couldn't balance on one leg for 10 seconds or more.

And that inability was correlated with a doubling of the risk of death from any cause in the next decade.

If you have trouble doing it, here are two good balance-building exercises:

1. Do three reps of heel-to-toe standing for five-plus seconds. Start with feet at hip-width apart, contract your core. Move your left foot in front of your right foot, heel to toe. Extend your arms straight out to the side at shoulder level. Repeat with right foot in front of left foot. That's one rep.

2. Do three sets of cross-overs. Stand straight with weight evenly distributed and arms at your side. Step to your right with your right foot; then cross in front with your left foot and step out again with your right foot; then cross behind with your left foot. Take 10 steps. Bring feet together. Then repeat, going to your left. That's one set.

If you have balance problems, see your doctor to check if your blood pressure, inner ear disruptions, arthritis, or medications are making you unsteady.