Differences In Wearable Running Power On Three Different Surfaces During Submaximal Running

Abstract

Running pace is one of the primary measures of running intensity, however, variations in grade and surface limit quantifying intensity solely based on pace. With the advent of wearable running power meters, runners can assess the external work stimulus inclusive of pace, grade, and surface. PURPOSE: To assess differences in running power (RP) on different surfaces, a Stryd running power meter was evaluated based on submaximal running on three different surfaces. METHODS: Eight collegiate cross country runners (male n=4, age=21.25±0.50 yrs, weight=63.45±9.73 kg, height=178.5±10.82 cm; female n=4, age=20±1.41 yrs, weight=56.45±4.95 kg, height=169.5±7.97 cm) participated in two trials of submaximal running at 85% of lactate threshold (LT) on each of three different surfaces: treadmill, grass, and track. All subjects completed a a VO2max and LT running test. For this investigation, sub-maximal running speed/pace was determined from the maximal effort / LT test. During subsequent submaximal running trials, ventilatory and metabolic measures and heart rate (HR) were collected with a portable breath by breath analyzer (COSMED K4B2) and HR monitor (Polar). For the track and grass submaximal running, the runners were paced by a cyclist maintaining a constant speed using a speedometer. ANOVAs were run between trials on all surfaces including treadmill, track and grass. RESULTS: The running power for the treadmill surface was significantly lower than both the grass and track (Mean±SE: RPtreadmill = 237±12.7 W*, RPgrass = 244±13.4 W, RPtrack = 242±13.0 W). There were no significant differences between grass and track surfaces (*p<0.05). CONCLUSIONS: This investigation found that running power (Stryd) is less when running on a treadmill compared to running on grass and a track which may indicate a different training stimulus when training on a treadmill versus other surfaces.