Case Study: The Effect Of Stride Frequency On The Over Ground Running Characteristics.

Abstract

There is a gap in the literature regarding the relationships between stride length (SL), stride frequency (SF), running velocity, and running performance. The majority of research on these relationships is based upon treadmill running. Although the overall running pattern is similar when running on a treadmill vs. overground (OG), there are unique differences. Besides, there are not many studies to focus on measuring the time to completion and running dynamics depend on SF variations during OG running. PURPOSE: To investigate the effect of change in SF on time to complete a specific distance and running dynamics during OG running. METHODS: One male subject (176cm, 79kg) completed a total of three OG running sessions at somewhat hard intensity. The given running distance was 2.4km (1.5 miles) and the participant was instructed to run the same route in three running conditions; running with preferred SF (PSF), faster SF (PSF+5%), and slower SF (PSF-5%). The first session was running with PSF, then 2 nd and 3 rd sessions were running with a target SF while listening to metronome sound using earbuds. Running dynamics (i.e., SL, SF, ground contact time: GCT, and vertical oscillation: VertO) were measured using a running pod (Running Dynamics Pod, Garmin), heart rate (HR) and running time were measured using a heart rate strap (HRM-Tri™, Garmin) and a sports watch (Forerunner 735XT, Garmin). RESULTS: Running velocity was qualitatively faster during PSF+5% than other conditions (PSF: 11 secs, PSF-5%: 1 min 33 secs), respectively. Both SL and GCT did not change noticeably across SF conditions. The VertO was highest at PSF condition and decreased in both conditions. HR was within a consistent range between the SF conditions.