Question: What's one of the strangest, most inexplicable times anyone might choose to disrobe?

Answer: "Paradoxical undressing" is well known to mountain rescuers who in freezing weather will encounter sufferers of hypothermia who refuse warming blankets and may even have removed some of their clothing, says "New Scientist" magazine.

In fact, 20 percent to 50 percent of deaths from hypothermia involve paradoxical undressing of some kind. One theory is that the fine blood vessels near the skin's surface contract to slow heat loss, then as contracting muscles become exhausted, blood rushes to the skin and causes a deep flush and sense of overheating. Now in the confusion of the moment, the victim disrobes to try to cool off. Or maybe the brain's overstressed hypothalamus goes awry.

Equally mysterious is "terminal burrowing," or "hide-and-die syndrome," seen also in certain cats and other species. When things get really bad, find somewhere to "curl up and die," which explains why some people are found dead behind wardrobes or under beds. One elderly man whose furnace had failed was discovered partly undressed and under overturned furniture, with bruises all over his hands. Police suspected foul play but an autopsy revealed hypothermia as the cause of death.

Question: Outfit a football helmet with a Head Impact Telemetry (HIT) System and now what tales of hard knocks might it tell? Listen up, coaches and docs.

Answer: The system — incorporating six accelerometers, a temperature sensor, plus a wireless signalling transceiver, is a little like having a doctor on the field who transmits data to the sidelines about the extent of blows to a player's head, the part of the helmet hit, etc, says Willie D. Jones in "IEEE Spectrum" magazine.

Since the HIT package sits inside the helmet right up against the head, the impact to the skull itself is measured (sides can be worse than the front or top). In one study, college players were found to endure 50 impacts per game of about 40 g's per blow, similar to that of a boxer. In other analyses, "lights-out" hits of pros often exceeded 100 g's, jarring as a car crash.

The signs of brain injury — headache, nausea, short-term memory loss — are tough for coaches and trainers to spot. So the HIT system is a real-time early-warning system to help determine if a player needs to sit out the rest of the game or get medical attention, perhaps for one of the estimated 230,000 football concussions annually in the United States.

Send STRANGE questions to brothers Bill and Rich at [email protected], coauthors of "Can a Guy Get Pregnant? Scientific Answers to Everyday (and Not-So- Everyday) Questions," from Pi Press.