Cited by 110Spaceflight effects on biologyTendon Structure and TreatmentUltrasound Imaging and Elastography

Effects of 20 days of bed rest on the viscoelastic properties of tendon structures in lower limb muscles

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Kubo, K, Akima, H, Ushiyama, J, Tabata, I, Fukuoka, H, Kanehisa, H, Fukunaga, T·2004·British Journal of Sports Medicine

Abstract

Objectives:The purpose of this study was to investigate the effects of 20 days’ bed rest on the viscoelastic properties of human tendon structures in knee extensor and plantar flexor muscles in vivo. Methods:Eight healthy men (age: 24±4 years, height: 172±9 m, body mass: 69±13 kg) carried out a 6° head-down bed rest for 20 days. Before and after bed rest, elongation (L) of the tendon and aponeurosis of vastus lateralis (VL) and medial gastrocnemius muscles (MG) during isometric knee extension and plantar flexion, respectively, were determined using real-time ultrasonic apparatus, while the subjects performed ramp isometric contraction up to the voluntary maximum, followed by ramp relaxation. The relationship between estimated muscle force (Fm) and tendon elongation (L) was fitted to a linear regression, the slope of which was defined as stiffness. The hysteresis was calculated as the ratio of the area within the Fm-L loop to the area beneath the load portion of the curve. Results:L values above 100 N were significantly greater after bed rest for VL, while there were no significant differences in L values between before and after for MG. The stiffness decreased after bed rest for VL (70.3±27.4 v 50.1±24.8 N/mm, before and after bed rest, respectively; p = 0.003) and MG (29.4±7.5 v 25.6±7.8 N/mm, before and after bed rest, respectively; p = 0.054). In addition, hysteresis increased after bed rest for VL (16.5±7.1%v 28.2±12.9%, before and after bed rest, respectively; p = 0.017), but not for MG (17.4±4.4%v 17.7±6.1%, before and after bed rest, respectively; p = 0.925). Conclusions:These results suggested that bed rest decreased the stiffness of human tendon structures and increased their hysteresis, and that these changes were found in knee extensors, but not the plantar flexors.

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  • Prolonged periods of bed rest result in significant atrophy of musculoskeletal mass and volume in the weight-bearing leg musculature such as the quadriceps femoris.

    “Prolonged periods of bed rest result in a significant atrophy of musculoskeletal mass and volume in the weight-bearing leg musculature such as the quadriceps femoris (5–8).”
  • This systematic review is in general agreement with the majority of other bed rest trials, which report that muscle strength is compromised to a greater extent than muscle size following bed rest.

    “Our systematic review is in general agreement with the majority of other bed rest trials, which report that muscle strength is compromised to a greater extent than muscle size following bed rest (6, 7, 10, 18, 19, 21–23, 56, 58).”

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Research works printed but not linked: 2

  1. Amiel D, Woo SLY, Harwood FL, et al. The effect of immobilization on collagen turnover in connective tissue: a biochemical-biomechanical correlation. Acta Orthop Scand 1982;53:325-32.
  2. Rollhauser H. Funktionelle Anpassung der Sehnenfaser im submikroskopischen Bereich. Z Anat Anzeig 1954;51:318-22.

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Authors
Kubo, K., Akima, H., Ushiyama, J., Tabata, I., Fukuoka, H., Kanehisa, H., & Fukunaga, T.
Affiliations
  • The University of Tokyo (JP)
  • Research Center of Health, Physical Fitness and Sports, Nagoya University (JP)
  • National Institute of Health and Nutrition (JP)
  • Waseda University (JP)
Corresponding author
Kubo, K
Venue
British Journal of Sports Medicine
Publisher
BMJ
Published
2004-05-21
Volume
38
Issue
3
Pages
324-330
ISSN
  • 0306-3674 (ISSN-L)
  • 1473-0480
OpenAlex
W2094400902
Cited by
110
References
30
Citations by year
2026: 4 · 2025: 5 · 2024: 6 · 2023: 9 · 2022: 3 · 2021: 8 · 2020: 4 · 2019: 5 · 2018: 7 · 2017: 1 · 2016: 4 · 2015: 1 · 2014: 3 · 2013: 7 · 2012: 6
FWCI
2.47
Type
journal article
Language
en
Open access
Licence
public-domain
Locations
  • British Journal of Sports Medicine (publishedVersion, public-domain)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Physiology › Spaceflight effects on biology
  • Health Sciences › Medicine › Orthopedics and Sports Medicine › Tendon Structure and Treatment
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Ultrasound Imaging and Elastography
Keywords
bed rest, tendon stiffness, hysteresis, vastus lateralis, medial gastrocnemius, knee extensors, plantar flexors
MeSH terms
Adult, Bed Rest, Elasticity, Electromyography, Foot, Humans, Isometric Contraction, Knee, Male, Tendons, Ultrasonography, Viscosity, Muscle, Skeletal

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