The Impact of Grounding in Running Shoes on Indices of Performance in Elite Competitive Athletes

Abstract

The introduction of carbon fiber plate shoes has triggered a plethora of world records in running, which has encouraged shoe industries to produce novel shoe designs to enhance running performance, including shoes containing conductor elements or "grounding shoes" (GS), which could potentially reduce the energy cost of running. The aim of this study was to examine the physiological and perceptual responses of athletes subjected to grounding shoes during running. Ten elite runners were recruited. Firstly, the athletes performed an incremental running test for VO₂max and anaerobic threshold (AT) determination, and were familiarized with the two shoe conditions (traditional training shoe (TTS) and GS, the latter containing a conductor element under the insole). One week apart, athletes performed running economy tests (20 min run at 80% of the AT) on a 400 m dirt track, with shoe conditions randomized. VO₂, heart rate, lactate, and perceived fatigue were registered throughout the experiment. No differences in any of the physiological or perceptual variables were identified between shoe conditions, with an equal running economy in both TTS and GS (51.1 ± 4.2 vs. 50.9 ± 5.1 mL kg^-1 min^-1, respectively). Our results suggest that a grounding stimulus does not improve the energy cost of running, or the physiological/perceptual responses of elite athletes.

Keywords: earthing; environmental physiology; grounding; running economy; running performance; shoe technology.

Figure 1

Image of the right grounding shoe (A) and traditional training shoe (B) for one of the elite athletes.

Figure 2

Protocol for the running economy trials at 80% of the anaerobic threshold (AT).

Figure 3

Mean and individual running economy values (mL kg⁻¹ min⁻¹) of the 10 athletes running in traditional training shoes (grey column) and in grounding shoes (black column).

Figure 4

Blood lactate (A), whole-body rate of perceived exertion (RPE; B), and legs-only RPE (C) during the recovery period after running in the traditional training shoe (TTS, gray solid line) or grounding shoe (GS, black solid line). Heart rate during the running economy trial in both TTS and GS trials (D). Dashed lines represent overlapping mean values between shoes.