Date of Project


Document Type

Honors Thesis

School Name

School of Movement and Rehabilitation Sciences


Exercise Science

Major Advisor

Dr. Sara Mahoney

Second Advisor

Dr. Andrew Carnes


The purpose of this investigation was to determine the accuracy of the GNSS (global navigation satellite system) in the Coros® Vertix 2 and Garmin® Fēnix 6 during two trail running conditions in a group of recreational trail runners. Six participants completed four self-paced, one-mile trail runs. Accuracy of the two watches in measuring distance were compared across two trail conditions, heavy and light tree coverage. Both watches were worn simultaneously and then switched to the opposite wrists for the next trial. Distance measured by the watches was reported every quarter mile. Mean and standard deviation of the distance measured by the watch were calculated for each condition. Conditions were compared using paired t-tests (α<0.05). The Garmin reported 0.93±0.03 miles and the Coros reported 0.94±0.02 miles for the one-mile trail. But overall, no difference in distance reported was detected between the two watches (p=0.43). The distance measured by the watches was significantly greater during the light tree coverage condition than the heavy tree coverage condition (p<0.01). Additionally, the distance was significantly greater while the watches were worn on the left wrist than worn on the right wrist (p=0.04). While there was no difference in accuracy between the two watches, this technology has limited accuracy in trail conditions. Both watches were, on average, under-reporting distance by 6-7%. Due to this accuracy level, athletes and coaches are advised to place less trust and dependency on these devices when planning training.

Available for download on Wednesday, May 01, 2024