Q: I have a couple long flights to Asia coming up and wonder what your thoughts are about exercising on the plane. I'm worried about circulation after sitting so long.
— Leslie B.

A. Hmmm, Leslie, considering my favorite bench press involves a burger and bratwurst, I may not be the best person to ask about exercise; but since your question entails a plane, I deem myself eminently qualified.

It looks to me that you're worried about Deep Vein Thrombosis or DVT, a condition also called Economy Class Syndrome. Basically, long periods of sitting still and inactivity can cause blood clots that may slow or stop blood flow. (Hopefully this doesn't apply to watching TV or time in a hammock.)

Medical experts don't suggest you drop and give us twenty on your next long-haul flight, but there is a consensus that travelers should consider some healthy diversions as in-flight preventative measures to avoid DVT. (See, you can exercise at 30,000 feet.) Medical experts suggest some of the following precautions may help:

Many airlines in the long-haul business have developed resources to address travelers' in-flight health concerns.

British Airways' online health and medical information section covers everything from planning your flight to jet lag.

Continental Airlines offers tips for healthy travel complete with some snappy drawings of in-flight exercises.

(Warning: the knee-to-chest stretch can elicit judgmental glares from fellow passengers, and threaten already weak trouser seams.)

Qantas also offers some helpful tips for your in-flight health, including an in-flight workout.

So Leslie, use your discretion in following the tips listed above. If you opt for a little in-flight stretch and isometrics, try it at home first. Sharp and unpracticed moves can leave crew members and fellow passengers lightly bruised and mildly dazed.

Have a question for Tom?
Tom Conway, who remembers last touching (and seeing) his toes in 1999, looks forward to your questions, comments and tips below: