Localization of damage in the human leg muscles induced by downhill running

Sumiaki Maeo, Yukino Ando, Hiroaki Kanehisa, Yasuo Kawakami

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

We investigated localization of damage within the knee extensors (KEs) and plantar flexors (PFs) induced by downhill running (DR) by using transverse relaxation time (T2)-weighted magnetic resonance imaging (MRI). Fourteen young adults performed 45-min DR (-15% slope) at their maximal tolerable velocity. At pre-and 24, 48, and 72 h post-exercise, T2-MRI was scanned and T2 values for each muscle composing KEs and PFs at proximal, middle, and distal sites were calculated. Maximal isometric torque and rate of torque development (RTD: 0-30, 0-50, 0-100, 0-200 ms) were also measured. Maximal torque significantly decreased in KEs (14-17%) and PFs (6-8%) at 24-48 h post-exercise, with greater reductions for KEs. RTD in all phases, except for 0-200 ms in PFs, significantly decreased in KEs (11-42%) and PFs (13-23%) at least at one time point post-exercise. T2 significantly increased at several sites (3-5%) in both muscle groups at 24 and/or 48 h post-exercise. Among the T2-increased sites, the peak effect size (Cohen's d) regarding T2 change was pronounced at proximal (1.05) and middle (1.64) vastus intermedius compared to the other sites (0.72-0.77). These results suggest that DR induces damage in both KEs and PFs, and especially affects proximal-middle sites of the vastus intermedius.

Original languageEnglish
Article number5769
JournalScientific Reports
Volume7
Issue number1
DOIs
Publication statusPublished - 2017 Dec 1

Fingerprint

Running
Leg
Knee
Muscles
Torque
Exercise
Quadriceps Muscle
Magnetic Resonance Imaging
Young Adult

ASJC Scopus subject areas

  • General

Cite this

Localization of damage in the human leg muscles induced by downhill running. / Maeo, Sumiaki; Ando, Yukino; Kanehisa, Hiroaki; Kawakami, Yasuo.

In: Scientific Reports, Vol. 7, No. 1, 5769, 01.12.2017.

Research output: Contribution to journalArticle

Maeo, Sumiaki ; Ando, Yukino ; Kanehisa, Hiroaki ; Kawakami, Yasuo. / Localization of damage in the human leg muscles induced by downhill running. In: Scientific Reports. 2017 ; Vol. 7, No. 1.
@article{ccb86e35c54144dc881e3580fcf0a40a,
title = "Localization of damage in the human leg muscles induced by downhill running",
abstract = "We investigated localization of damage within the knee extensors (KEs) and plantar flexors (PFs) induced by downhill running (DR) by using transverse relaxation time (T2)-weighted magnetic resonance imaging (MRI). Fourteen young adults performed 45-min DR (-15{\%} slope) at their maximal tolerable velocity. At pre-and 24, 48, and 72 h post-exercise, T2-MRI was scanned and T2 values for each muscle composing KEs and PFs at proximal, middle, and distal sites were calculated. Maximal isometric torque and rate of torque development (RTD: 0-30, 0-50, 0-100, 0-200 ms) were also measured. Maximal torque significantly decreased in KEs (14-17{\%}) and PFs (6-8{\%}) at 24-48 h post-exercise, with greater reductions for KEs. RTD in all phases, except for 0-200 ms in PFs, significantly decreased in KEs (11-42{\%}) and PFs (13-23{\%}) at least at one time point post-exercise. T2 significantly increased at several sites (3-5{\%}) in both muscle groups at 24 and/or 48 h post-exercise. Among the T2-increased sites, the peak effect size (Cohen's d) regarding T2 change was pronounced at proximal (1.05) and middle (1.64) vastus intermedius compared to the other sites (0.72-0.77). These results suggest that DR induces damage in both KEs and PFs, and especially affects proximal-middle sites of the vastus intermedius.",
author = "Sumiaki Maeo and Yukino Ando and Hiroaki Kanehisa and Yasuo Kawakami",
year = "2017",
month = "12",
day = "1",
doi = "10.1038/s41598-017-06129-8",
language = "English",
volume = "7",
journal = "Scientific Reports",
issn = "2045-2322",
publisher = "Nature Publishing Group",
number = "1",

}

TY - JOUR

T1 - Localization of damage in the human leg muscles induced by downhill running

AU - Maeo, Sumiaki

AU - Ando, Yukino

AU - Kanehisa, Hiroaki

AU - Kawakami, Yasuo

PY - 2017/12/1

Y1 - 2017/12/1

N2 - We investigated localization of damage within the knee extensors (KEs) and plantar flexors (PFs) induced by downhill running (DR) by using transverse relaxation time (T2)-weighted magnetic resonance imaging (MRI). Fourteen young adults performed 45-min DR (-15% slope) at their maximal tolerable velocity. At pre-and 24, 48, and 72 h post-exercise, T2-MRI was scanned and T2 values for each muscle composing KEs and PFs at proximal, middle, and distal sites were calculated. Maximal isometric torque and rate of torque development (RTD: 0-30, 0-50, 0-100, 0-200 ms) were also measured. Maximal torque significantly decreased in KEs (14-17%) and PFs (6-8%) at 24-48 h post-exercise, with greater reductions for KEs. RTD in all phases, except for 0-200 ms in PFs, significantly decreased in KEs (11-42%) and PFs (13-23%) at least at one time point post-exercise. T2 significantly increased at several sites (3-5%) in both muscle groups at 24 and/or 48 h post-exercise. Among the T2-increased sites, the peak effect size (Cohen's d) regarding T2 change was pronounced at proximal (1.05) and middle (1.64) vastus intermedius compared to the other sites (0.72-0.77). These results suggest that DR induces damage in both KEs and PFs, and especially affects proximal-middle sites of the vastus intermedius.

AB - We investigated localization of damage within the knee extensors (KEs) and plantar flexors (PFs) induced by downhill running (DR) by using transverse relaxation time (T2)-weighted magnetic resonance imaging (MRI). Fourteen young adults performed 45-min DR (-15% slope) at their maximal tolerable velocity. At pre-and 24, 48, and 72 h post-exercise, T2-MRI was scanned and T2 values for each muscle composing KEs and PFs at proximal, middle, and distal sites were calculated. Maximal isometric torque and rate of torque development (RTD: 0-30, 0-50, 0-100, 0-200 ms) were also measured. Maximal torque significantly decreased in KEs (14-17%) and PFs (6-8%) at 24-48 h post-exercise, with greater reductions for KEs. RTD in all phases, except for 0-200 ms in PFs, significantly decreased in KEs (11-42%) and PFs (13-23%) at least at one time point post-exercise. T2 significantly increased at several sites (3-5%) in both muscle groups at 24 and/or 48 h post-exercise. Among the T2-increased sites, the peak effect size (Cohen's d) regarding T2 change was pronounced at proximal (1.05) and middle (1.64) vastus intermedius compared to the other sites (0.72-0.77). These results suggest that DR induces damage in both KEs and PFs, and especially affects proximal-middle sites of the vastus intermedius.

UR - http://www.scopus.com/inward/record.url?scp=85024894599&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85024894599&partnerID=8YFLogxK

U2 - 10.1038/s41598-017-06129-8

DO - 10.1038/s41598-017-06129-8

M3 - Article

VL - 7

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

IS - 1

M1 - 5769

ER -