Walk-to-run-transition Cadence In 18-20 Year Olds: The SKyRoCKeT Study

PURPOSE: Running, a vigorous-intensity type of physical activity, is a basic component of human ambulation. Findings indicate that adults 21 - 60 years of age tend to transition from walking to running at a cadence between 135 - 140 steps/min. However, limited data is available concerning cadence indicative of the walk-to-run transition (WRT) for younger adults 18 - 20 years of age. METHODS: Forty-five young people (42.2% women; mean age = 19.0 [standard deviation, SD 0.78] years; mean body mass index = 23.7 [SD 4.0] kg/m2) completed a series of five-minute treadmill bouts, progressively increasing in speed from 0.22 - 2.68 meters/sec (m/s) in 0.22 m/s increments at 0% grade. Participants, all medically screened for conditions that would impact their ability to run, had two minutes of standing rest between bouts and ran at least one bout. Cadence was directly observed and hand-tallied, with video recording for backup verification as needed. Researchers noted the speed at which a participant began to run. Each participant’s initial running bout and the preceding walking bout were extracted. The WRT cadence indicator was determined via receiver operating characteristic (ROC) curve analysis by identifying the cadence that maximized Youden’s index (YI), combining both sensitivity (Se) and specificity (Sp) to determine diagnostic accuracy. Se, Sp, and the area under the curve (AUC) were also computed. RESULTS: The WRT cadence indicator identified from the ROC curve analysis was 134.6 steps/min (95% CI: 126.5 - 135.6). This threshold correctly identified participants who were running 84% of the time (Se = 0.84) and correctly identified participants who were walking 100% of the time (Sp = 1); thus, YI was 0.84. Overall, the WRT cadence indicator was a highly accurate classifier (AUC = 0.97). CONCLUSIONS: The identified WRT cadence indicator of 134.6 steps/min approximately aligns with the established WRT cadence range for adults aged 21 to 60 (135 - 140 steps/min). This indicator serves as a valuable tool for analyzing wearable technology data in the context of cadence identification or programming for running. Furthermore, this information can inform public health initiatives focused on young adults, promoting physical activity and recreational running within a cadence range that coincides with natural movement patterns. R01HD105768