Effect of stride frequency on thermoregulatory responses during endurance running in distance runners

Tatsuro Amano; Masaki Ishitobi; Yukio Ogura; Yoshimitsu Inoue; Shunsaku Koga; Takeshi Nishiyasu; Narihiko Kondo

doi:10.1016/j.jtherbio.2016.08.005

Effect of stride frequency on thermoregulatory responses during endurance running in distance runners

J Therm Biol. 2016 Oct:61:61-66. doi: 10.1016/j.jtherbio.2016.08.005. Epub 2016 Aug 23.

Authors

Tatsuro Amano¹, Masaki Ishitobi², Yukio Ogura³, Yoshimitsu Inoue³, Shunsaku Koga⁴, Takeshi Nishiyasu⁵, Narihiko Kondo⁶

Affiliations

¹ Laboratory for Applied Human Physiology, Graduate School of Human Development and Environment, Kobe University, 3-11 Tsurukabuto, Nada-ku, Kobe, Japan; Laboratory for Exercise and Environmental Physiology, Faculty of Education, Niigata University, Niigata, Japan.
² Laboratory for Applied Human Physiology, Graduate School of Human Development and Environment, Kobe University, 3-11 Tsurukabuto, Nada-ku, Kobe, Japan.
³ Laboratory for Human Performance Research, Osaka International University, Osaka, Japan.
⁴ Applied Physiology Laboratory, Kobe Design University, Kobe, Japan.
⁵ Institute of Health and Sports Science, University of Tsukuba, Tsukuba, Japan.
⁶ Laboratory for Applied Human Physiology, Graduate School of Human Development and Environment, Kobe University, 3-11 Tsurukabuto, Nada-ku, Kobe, Japan. Electronic address: kondo@kobe-u.ac.jp.

PMID: 27712662
DOI: 10.1016/j.jtherbio.2016.08.005

Abstract

Changing stride frequency may influence oxygen uptake and heart rate during running as a function of running economy and central command. This study investigated the influence of stride frequency manipulation on thermoregulatory responses during endurance running. Seven healthy endurance runners ran on a treadmill at a velocity of 15km/h for 60min in a controlled environmental chamber (ambient temperature 27°C and relative humidity 50%), and stride frequency was manipulated. Stride frequency was intermittently manipulated by increasing and decreasing frequency by 10% from the pre-determined preferred frequency. These periods of increase or decrease were separated by free frequency running in the order of free stride frequency, stride frequency manipulation (increase or decrease), free stride frequency, and stride frequency manipulation (increase or decrease) for 15min each. The increased and decreased stride frequencies were 110% and 91% of the free running frequency, respectively (196±6, 162±5, and 178±5steps/min, respectively, P<0.01). Compared to the control, stride frequency manipulation did not affect rectal temperature, heart rate, or the rate of perceived exhaustion during running. Whole-body sweat loss increased significantly when stride frequency was manipulated (1.48±0.11 and 1.57±0.11kg for control and manipulated stride frequencies, respectively, P<0.05), but stride frequency had a small effect on sweat loss overall (Cohen's d=0.31). A higher mean skin temperature was also observed under mixed frequency conditions compared to that in the control (P<0.05). While the precise mechanisms underlying these changes remain unknown (e.g. running economy or central command), our results suggest that manipulation of stride frequency does not have a large effect on sweat loss or other physiological variables, but does increase mean skin temperature during endurance running.

Keywords: Coaching; Marathon; Non-thermal sweating; Running economy; Thermoregulation.

MeSH terms

Adult
Body Temperature
Body Temperature Regulation*
Humans
Male
Physical Endurance*
Running*
Skin Temperature
Sweating
Young Adult