Article
Physiology
Qingshan Zhang, Baptiste Morel, Robin Trama, Christophe A. Hautier
Summary: This study examined the effects of fatigue on knee extensor and flexor muscles in professional soccer players. Fatigue resulted in a significant decrease in T-peak, RTD, and RER, without changes in RMSmean. The impact of fatigue on muscle activation was more prominent in the first 100 ms of movement, influencing injury risk more than any changes in H/Q ratios.
FRONTIERS IN PHYSIOLOGY
(2021)
Article
Sport Sciences
Anasthase Massamba, Elyse Hucteau, Joris Mallard, Guillaume P. P. Ducrocq, Fabrice Favret, Thomas J. J. Hureau
Summary: This study investigated the mechanisms of neuromuscular fatigue in quadriceps and hamstring muscles and its impact on the torque-duration relationship. The results showed that quadriceps and hamstring muscles exhibit different etiology and magnitude of neuromuscular fatigue, with no correlation observed between the two muscle groups. This highlights the importance of specifically studying hamstring muscle fatigue.
MEDICINE & SCIENCE IN SPORTS & EXERCISE
(2022)
Article
Chemistry, Multidisciplinary
Ricardo Pimenta, Tomas Lopes, Paula Bruno, Antonio Veloso
Summary: The aim of this study is to compare the effects of previous hamstring strain injury on sprint performance, hamstrings shear modulus pattern, and neuromuscular parameters between players with and without injury. The results suggest that there are no differences between previously injured and healthy control players, except for the early rate of torque development in the biceps femoris long head muscle. These findings indicate that the differences between injured and control groups may recover over time.
APPLIED SCIENCES-BASEL
(2023)
Article
Orthopedics
Keith A. Knurr, Daniel G. Cobian, Stephanie A. Kliethermes, Mikel R. Stiffler-Joachim, Bryan C. Heiderscheit
Summary: This study assessed the influence of recovery in quadriceps peak torque (PT) and rate of torque development (RTD) symmetry on knee kinematic and kinetic symmetry during running over the initial 2 years after anterior cruciate ligament reconstruction (ACLR). The results showed that quadriceps RTD was more strongly associated with knee biomechanics symmetry during running compared to PT or time.
AMERICAN JOURNAL OF SPORTS MEDICINE
(2023)
Article
Rehabilitation
Ginji Nara, Mina Samukawa, Kensuke Oba, Yuta Koshino, Tomoya Ishida, Satoshi Kasahara, Harukazu Tohyama
Summary: The knee flexion angle has an impact on torque and rate of torque development in athletes with hamstring strain injury, particularly at 30 degrees of flexion where the injured limb shows significant torque deficits.
PHYSICAL THERAPY IN SPORT
(2022)
Article
Orthopedics
Argell T. San Jose, Nirav Maniar, Ryan G. Timmins, Kate Beerworth, Chris Hampel, Natalie Tyson, Morgan D. Williams, David A. Opar
Summary: There are differences in maximal and explosive strength symmetry between males and females during rehabilitation after ACLR. Maximal concentric hamstring and quadriceps asymmetry decreased from early to late rehabilitation, but explosive quadriceps asymmetry did not improve. Females had larger quadriceps strength asymmetry than males throughout rehabilitation.
KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY
(2023)
Article
Multidisciplinary Sciences
Kushla Nand Sharma, Nishat Quddus, Unaise Abdul Hameed, Sohrab Ahmad Khan, Anita Kumari, Ahmad H. Alghadir, Masood Khan
Summary: This study found that 6 weeks of eccentric and concentric isokinetic training of the hamstring increased PTecc and PTecc/PTcon, while decreasing AThams and ATquad. The effects of eccentric and concentric isokinetic training on PTecc, PTecc/PTcon, AThams, and ATquad were not mode specific.
Article
Orthopedics
Benjamin D. Brightwell, Joshua J. Van Wyngaarden, Michael A. Samaan, Paul E. Matuszewski, Cale A. Jacobs, Brian Noehren
Summary: Quadriceps performance is impaired 12 months after surgical repair of a lower extremity fracture, particularly in female participants, in cases requiring external fixation, and in those with higher kinesiophobia 12 months after surgery.
Article
Neurosciences
Amy R. Sibley, Siobhan Strike, Sarah C. Moudy, Neale A. Tillin
Summary: The study found that quadriceps strength asymmetry is more apparent in gait asymmetry during fast walking, and there is a close association between strength and gait asymmetry in habitual and fast walking speeds.
Article
Sport Sciences
Erik Wilmes, Cornelis J. De Ruiter, Bram J. C. Bastiaansen, Edwin A. Goedhart, Michel S. Brink, Frans C. T. Van der Helm, Geert J. P. Savelsbergh
Summary: During a football match simulation, hamstring maximal voluntary torque declines, which is associated with increased peak knee extension and peak combined angle during sprinting, indicating a reduced capacity of the muscles to decelerate the lower leg with fatigue.
MEDICINE & SCIENCE IN SPORTS & EXERCISE
(2021)
Article
Rehabilitation
Gulcan Harput, Volga B. Tunay, Matthew P. Ithurburn
Summary: The study found that quadriceps and hamstring strength of the involved limb consistently increased over the first 6 months following ACLR, while the uninvolved limb strength remained stable. However, only approximately 16% of participants achieved a limb symmetry index greater than 90% for both quadriceps and hamstring strength at 6 months post-ACLR, which is the typically recommended cutoff value for return to sport.
JOURNAL OF SPORT REHABILITATION
(2021)
Article
Engineering, Biomedical
Derrick Lim, Mikael Del Castillo, Austin J. Bergquist, Matija Milosevic, Kei Masani
Summary: This study systematically investigated the contribution of individual motor points of the quadriceps femoris muscle to knee joint torque during paired electrical stimuli. The results showed significant differences in torque contributions among the motor points, demonstrating the potential for selective activation of muscle groups using NMES. These findings provide valuable information for designing rehabilitation protocols utilizing NMES on the quadriceps femoris muscles.
IEEE TRANSACTIONS ON NEURAL SYSTEMS AND REHABILITATION ENGINEERING
(2021)
Article
Environmental Sciences
Gurkan Diker, Artur Struzik, Sadi On, Raif Zileli
Summary: The correct torque ratio between the knee joint extensor and flexor muscle groups is important for preventing injuries. However, the relationship between the hamstring-to-quadriceps ratio and sport performance is unclear. This study found a significant relationship between the H/Q ratio and sprint times, suggesting the importance of knee joint extensors in sprinting.
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
(2022)
Article
Sport Sciences
Padraig Spillane, Theo M. Bampouras
Summary: Environmental temperature changes within the examined range do not affect the ability to generate maximum torque or any of the RTD parameters in maximum voluntary isometric contractions. However, increased heat results in higher RTD in electrically stimulated contractions, most likely due to reduced contraction time.
EUROPEAN JOURNAL OF SPORT SCIENCE
(2021)
Article
Orthopedics
M. T. Murphy, N. Wang, D. T. Felson, M. C. Nevitt, C. E. Lewis, L. Frey-Law, A. Guermazi, N. A. Segal
Summary: This study found that women had higher levels of knee flexor coactivation than men, and in men, knee flexor coactivation was more strongly associated with worsening cartilage morphology.
OSTEOARTHRITIS AND CARTILAGE
(2022)
Article
Rehabilitation
Kamiar Ghoseiri, Mohammad Yusuf Rastkhadiv, Mostafa Allami, Phillip Page, Lars L. Andersen, Duane C. Button
Summary: This study aimed to investigate pain sensitivity and its association with prosthesis use in veterans with transtibial amputation. The findings showed significant differences in pain sensitivity among different anatomical locations and participants, and longer prosthesis use was associated with increased pain sensitivity.
ASSISTIVE TECHNOLOGY
(2023)
Article
Rehabilitation
Linda Fernandes, Allan Villadsen, Christina Enciso Holm, Michala Skovlund Sorensen, Mette Kreutzfeldt Zebis, Lars Louis Andersen, Michael Mork Petersen
Summary: The aim of this study was to evaluate work ability, activity limitations and physical activity in adults who had undergone major bone sarcoma resection and reconstruction surgery. The results showed that, despite similar levels of physical activity, patients exhibited poorer work ability and severe activity limitations.
DISABILITY AND REHABILITATION
(2023)
Article
Orthopedics
Bo Bregenhof, Per Aagaard, Nis Nissen, Mark W. Creaby, Jonas Bloch Thorlund, Carsten Jensen, Trine Torfing, Anders Holsgaard-Larsen
Summary: For patients with persistent hamstring strength deficits after ACL reconstruction, 12 weeks of supervised progressive strength training was found to be more effective than low-intensity home-based exercises for improving maximal knee flexor muscle strength and some patient-reported outcomes.
JOURNAL OF ORTHOPAEDIC & SPORTS PHYSICAL THERAPY
(2023)
Article
Hematology
Joaquin Calatayud, Daniel C. Ogrezeanu, Juan J. Carrasco, Eduardo Martinez-Valdes, Sofia Perez-Alenda, Carlos Cruz-Montecinos, Lars L. Andersen, Per Aagaard, Luis Suso-Marti, Jose Casana
Summary: This study aimed to compare the safety, feasibility, and neuromuscular activity of low-load resistance exercise with/without blood flow restriction (BFR) in people with severe hemophilia. The results showed that BFR did not cause pain increases or adverse events, and there were no significant changes in neuromuscular activity. Therefore, it is safe and feasible for these patients to perform exercise with low load and appropriate BFR.
EUROPEAN JOURNAL OF HAEMATOLOGY
(2023)
Article
Public, Environmental & Occupational Health
Lars Louis Andersen, Jonas Vinstrup, Joaquin Calatayud, Ruben Lopez-Bueno, Thomas Clausen, Claus Manniche
Summary: This study examines the association between the use of analgesics and anxiolytic/sedative/hypnotic (ASH) medication and the risk of disability pension and mortality. The results show that frequent use of these medications increases the risk of disability pension and early death among workers. Better management of musculoskeletal and mental health conditions, without excessive medication use, is necessary.
EUROPEAN JOURNAL OF PUBLIC HEALTH
(2023)
Article
Public, Environmental & Occupational Health
Sebastian Venge Skovlund, Jonas Vinstrup, Emil Sundstrup, Lars Louis Andersen
Summary: The study investigates the association between self-reported work limitations due to musculoskeletal pain and loss of paid employment among senior workers in Denmark. The results show that work-limiting pain progressively increases the risk of loss of paid employment. Preventive efforts at both policy and workplace levels should be implemented for senior workers with physically demanding work.
EUROPEAN JOURNAL OF PUBLIC HEALTH
(2023)
Article
Physiology
Tobias Goetschi, Victoria Held, Gianna Klucker, Barbara Niederoest, Per Aagaard, Joerg Spoerri, Fabian S. Passini, Jess G. Snedeker
Summary: Prolonged periods of increased physical demands can cause both positive and negative adaptations in tendons, depending on the underlying mechanisms. The PIEZO1 ion channel has been implicated in tendon mechanotransduction and the E756del gain-of-function variant has been linked to improved jumping performance. This study found that carrying the E756del gene variant was associated with increased patellar tendon stiffness in humans, but there was no correlation between tendon stiffness and jumping performance.
JOURNAL OF APPLIED PHYSIOLOGY
(2023)
Article
Physiology
Christopher T. A. Lewis, Lee Tabrizian, Joachim Nielsen, Jenni Laitila, Thomas N. Beck, Mathilde S. Olsen, Marija M. Ognjanovic, Per Aagaard, Rune Hokken, Simon Laugesen, Arthur Ingersen, Jesper L. Andersen, Casper Soendenbroe, Jorn W. Helge, Flemming Dela, Steen Larsen, Ronni E. Sahl, Tue Romer, Mikkel T. Hansen, Jacob Frandsen, Charlotte Suetta, Julien Ochala
Summary: Lewis et al. investigated the influence of training status on relaxed myosin conformations and found that moderate physical activity leads to a shift in relaxed myosin conformation, resulting in reduced ATP consumption. Their study revealed that physical activity level and training type can influence resting skeletal muscle myosin dynamics, suggesting that environmental stimuli such as exercise can rewire the molecular metabolism of human skeletal muscle through myosin.
JOURNAL OF GENERAL PHYSIOLOGY
(2023)
Article
Neurosciences
Javier Botella, Camilla T. Schytz, Thomas F. Pehrson, Rune Hokken, Simon Laugesen, Per Aagaard, Charlotte Suetta, Britt Christensen, Niels Ortenblad, Joachim Nielsen
Summary: This study investigated the mitochondrial structural characteristics in skeletal muscle of strength athletes compared to untrained controls. The results showed that strength athletes had increased mitochondrial cristae density, decreased mitochondrial size, and increased surface-to-volume ratio in their mitochondrial pool, despite similar mitochondrial volume density. In addition, resistance exercise led to mild mitochondrial stress but did not increase the number of damaged mitochondria. Moreover, the study found that acute resistance exercise increased the expression of markers of mitochondrial biogenesis, fission, and mitochondrial unfolded protein responses (UPRmt), and strength-trained individuals showed an enrichment of the UPRmt in their basal transcriptome. These findings suggest that strength athletes have a unique mitochondrial remodeling that minimizes the space required for mitochondria.
JOURNAL OF PHYSIOLOGY-LONDON
(2023)
Review
Physiology
M. H. Hjortshoej, P. Aagaard, C. D. Storgaard, H. Juneja, J. Lundbye-Jensen, S. P. Magnusson, C. Couppe
Summary: This study evaluated the hormonal, immune, and oxidative stress responses in healthy adults following low-load blood-flow restricted resistance exercise (LL-BFRRE) and conventional free-flow resistance exercise (FFRE). The results showed that LL-BFRRE induced higher hormone and immune responses compared to FFRE, and had attenuated oxidative stress responses compared to HL-FFRE.
Article
Public, Environmental & Occupational Health
Jonas Christian Lunen, Reiner Rugulies, Jeppe K. Sorensen, Lars L. Andersen, Thomas Clausen
Summary: This study found a significant correlation between cumulative exposure to multiple psychosocial work factors and the onset of depressive disorder and long-term sickness absence.
EUROPEAN JOURNAL OF PUBLIC HEALTH
(2023)
Article
Sport Sciences
M. J. Johansen, P. Aagaard, K. D. Gejl, T. Kvorning, J. Bojsen-Moller
Summary: This study examined the relationship between maximal club head speed (CHS) and physiological and anthropometric factors in 21 national-level male golfers. The study found that CHS was positively correlated with measures of strength, power, and trunk rotation. Participants with high CHS demonstrated greater strength, power, and trunk rotation compared to those with low CHS. Improving neuromuscular strength and power may be important for golfers to increase CHS and driving distance.
JOURNAL OF SPORTS SCIENCES
(2023)
Article
Biophysics
Jon Skovgaard Jensen, Anders Holsgaard-Larsen, Anders Stengaard Sorensen, Per Aagaard, Jens Bojsen-Moller
Summary: This study investigates the biomechanical effects of robot-assisted body weight unloading (BWU) on gait patterns in healthy young adults. The results show that dynamic robot-assisted BWU enables reduced kinetic requirements without distorting biomechanically normal gait patterns during overground walking.
JOURNAL OF BIOMECHANICS
(2024)
Article
Psychology, Clinical
Rodrigo Nunez-Cortes, Ander Espin, Joaquin Calatayud, Sofia Perez-Alenda, Carlos Cruz-Montecinos, Ruben Lopez-Bueno, Jonas Vinstrup, Markus D. Jakobsen, Lars Louis Andersen
Summary: This study examined the association between vitality, mental health, and increased upper extremity pain intensity among female hospital nurses. The results showed significant associations between low vitality levels and the odds of shoulder pain and hand/wrist pain. Additionally, moderate levels of mental health were associated with increased odds of shoulder pain at follow-up.
EUROPEAN JOURNAL OF INVESTIGATION IN HEALTH PSYCHOLOGY AND EDUCATION
(2023)