Bagged Arms Go Numb

A question that comes across my desk semi-often is this: why do my arms go numb from the elbow to the hand after a night in my sleeping bag? The numbness usually can be explained by the fact that people sleep differently in their bags. With less room, they curl their arms at the elbows and often at the wrists as well, especially if they snooze with their hands tucked under their chins. This position, if prolonged, will irritate the median and/or ulnar nerves, and the result is numbness. On the positive side, nothing serious is happening, and soon after the arms are straightened, the numbness goes harmlessly away. If folks had rather avoid the problem, they can try a bigger and/or more insulated bag. Bigger, of course, means more room and less need for elbow flexion. More insulated could mean sleeping warmer with less need to curl up to hold in body heat.