You can see the speed increase in the second half of the race (be aware that my Nike+ tracker is off significantly for speed and distance when compared to my Garmin)
{"Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CS6 (Windows)", "Image DateTime": "2014:05:14 19:16:23", "Image ExifOffset": "164", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "302", "Thumbnail JPEGInterchangeFormatLength": "3606", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "588", "EXIF ExifImageLength": "408"}