You probably don't spend much time at all thinking about how fast you walk or how strong your grip is.

But maybe you should -- because a new study shows how these basic tests could help predict serious health problems years down the road.

Researchers from the Boston Medical Center measured the grip strength, walking speeds and cognitive function of more than 2,400 people with an average age of 62, and then tracked them for an average of 11 years.

They found that the slowest-walking volunteers who were middle aged at the start of the study were 50 percent more likely to face dementia 11 years later than faster walkers.

Slower walkers also had less overall brain volume -- another dementia warning sign -- and did worse on memory, language and decision-making tests, according to research presented at the annual meeting of the American Academy of Neurology.

That should be enough to make you want to pick up the pace as you walk -- and while you're at it, you might want to work on a firmer handshake, too: The study also found that people with a stronger grip at the age of 65 had a 42 percent lower risk of a stroke or mini stroke than those with weaker grips.

That strong grip was also linked to larger brain volume and better performance on some cognitive tests.

It's not the first study to link the telltale signs of frailty to poor health. One study from just a few months back found that people who walk the slowest have a much higher risk of an early death. Other studies have found that slower walkers are more likely to face heart attacks and other heart-related problems.

It's not the walk or grip itself that's causing any of this, of course. These conditions are often the subtle early warning signs of physical or neurological problems -- and it might not always be obvious even to yourself when you've lost a step or two or let loose on your grip.

But if you find yourself lagging behind your friends or you don't quite feel the power you used to, don't ignore it. Get yourself checked out now so you don't have to face these other problems later.