title: Shear-Wave Elastography Assessments of Quadriceps Stiffness Changes prior to, during and after Prolonged Exercise: A Longitudinal Study during an Extreme Mountain Ultra-Marathon.
abstract: In sports medicine, there is increasing interest in quantifying the elastic properties of skeletal muscle, especially during extreme muscular stimulation, to improve our understanding of the impact of alterations in skeletal muscle stiffness on resulting pain or injuries, as well as the mechanisms underlying the relationships between these parameters. Our main objective was to determine whether real-time shear-wave elastography (SWE) can monitor changes in quadriceps muscle elasticity during an extreme mountain ultra-marathon, a powerful mechanical stress model. Our study involved 50 volunteers participating in an extreme mountain marathon (distance: 330 km, elevation: +24,000 m). Quantitative SWE velocity and shear modulus measurements were performed in most superficial quadriceps muscle heads at the following 4 time points: before the race, halfway through the race, upon finishing the race and after recovery (+48 h). Blood biomarker levels were also measured. A significant decrease in the quadriceps shear modulus was observed upon finishing the race (3.31±0.61 kPa) (p<0.001) compared to baseline (3.56±0.63 kPa), followed by a partial recovery +48 h after the race (3.45±0.6 kPa) (p = 0.002) across all muscle heads, as well as for each of the following three muscle heads: the rectus femoris (p = 0.003), the vastus medialis (p = 0.033) and the vastus lateralis (p = 0.001). Our study is the first to assess changes in muscle stiffness during prolonged extreme physical endurance exercises based on shear modulus measurements using non-invasive SWE. We concluded that decreases in stiffness, which may have resulted from quadriceps overuse in the setting of supra-physiological stress caused by the extreme distance and unique elevation of the race, may have been responsible for the development of inflammation and muscle swelling. SWE may hence represent a promising tool for monitoring physiologic or pathological variations in muscle stiffness and may be useful for diagnosing and monitoring muscle changes.
authors: Department of Radiology, CHU Saint-Etienne, Université Jean-Monnet, Saint-Étienne, France.
authors: Pierre
authors: P
authors: Andonian
authors: Department of Radiology, CHU Saint-Etienne, Université Jean-Monnet, Saint-Étienne, France.|Univ Lyon, UJM-Saint-Etienne, INSA, CNRS UMR 5520, INSERM U1206, CREATIS, F-42023, Saint-Etienne, France.
authors: Magalie
authors: M
authors: Viallon
authors: EuSpLM, Department of Clinical Chemistry, University of Liège, CHU Sart-Tilman, Liège, Belgium.
authors: Caroline
authors: C
authors: Le Goff
authors: Department of Radiology, CHU Saint-Etienne, Université Jean-Monnet, Saint-Étienne, France.
authors: Charles
authors: C
authors: de Bourguignon
authors: Department of Intensive Care, CHU Saint-Etienne, Saint-Etienne, France.
authors: Charline
authors: C
authors: Tourel
authors: Department of Intensive Care, CHU Saint-Etienne, Saint-Etienne, France.
authors: Jérome
authors: J
authors: Morel
authors: Department of Neurology and Neurophysiology, Mountain Medicine Center, Valle d'Aosta Regional Hospital, Aosta, Italy.
authors: Guido
authors: G
authors: Giardini
authors: Department of Intensive Care, CHU Saint-Etienne, Saint-Etienne, France.
authors: Laurent
authors: L
authors: Gergelé
authors: Institute of Sport Sciences of the University of Lausanne (ISSUL), Lausanne, Switzerland.
authors: Grégoire P
authors: GP
authors: Millet
authors: Department of Radiology, CHU Saint-Etienne, Université Jean-Monnet, Saint-Étienne, France.|Univ Lyon, UJM-Saint-Etienne, INSA, CNRS UMR 5520, INSERM U1206, CREATIS, F-42023, Saint-Etienne, France.
authors: Pierre
authors: P
authors: Croisille
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D052097:Quadriceps Muscle / Q000000981:diagnostic imaging / Q000502:physiology*; D012420:Running / Q000502:physiology*; D033081:Shear Strength; D013314:Stress, Mechanical
chemical_list: D015415:Biomarkers