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+The data contained here are from 50 healthy children ranging in age
+from 40 months to 163 months. Each data file is named with a subject
+identifier (1-50) and the subject's age (e.g., the file name 2-45.txt
+indicates that subject #2 is 45 months old).  Each data file contains
+two columns of data in text format. The first column is the time (in
+seconds), and the second column is the stride interval (in seconds)
+or the gait cycle duration, the time from heel strike to heel strike
+of the same foot.
+
+For more information, please see Hausdorff et al.,
+Journal of  Applied Physiology, vol.  86: 1040-1047, 1999 or 
+contact Dr. Jeff Hausdorff at jhausdor@bidmc.harvard.edu.