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Gender differences among long-distance backpackers: A prospective study of women Appalachian Trail backpackers.

OBJECTIVE
Backpacking is a popular recreational activity, yet the differential experiences of women are unknown. The objective was to compare women with men backpackers to determine the extent to which injuries and illnesses limit endurance outdoor recreational activities.


METHODS
This was a prospective cohort surveillance survey of 334 persons who hiked the Appalachian Trail for > or =7 days. At the end of their hike, 280 subjects completed a questionnaire. Male hikers served as controls for injury and illness.


RESULTS
Women comprised 26% (72 of 280) of the sample. The mean (+/-SD) duration of hiking was 144 +/- 66 days covering 1570 +/- 680 miles. Fifty-seven percent (41 of 72) of women and 72% (150 of 208) of men attained their goal (P = .02). The occurrence of individual musculoskeletal problems, such as strains, sprains, arthralgias, tendonitis, and fractures, were similar (P = .9) between sexes. The occurrence of diarrhea (56%) was also similar (relative risk [RR] 1.0; P = .9) between sexes. Of regularly menstruating women, 87% (43 of 49) had menstrual changes while hiking, such as change in frequency (45%) or character (43%) (RR 3.1; 95% CI, 2.0-4.8; P < .001). Shortened duration of menses was most common (41%). Amenorrhea occurred in 22% (11 of 49) of women, including 5 of 25 taking oral contraceptive pills (OCPs). Breakthrough, midcycle bleeding occurred in 20% (10 of 49) of women.


CONCLUSIONS
Women had similar experiences as compared with men when backpacking. Menstrual changes were very common including amenorrhea. Prolonged amenorrhea raises concern for potential bone mineral density loss, and OCPs should be considered to prevent such loss.