Objective: Existing isokinetic contractions are characterized using standardized angular velocities, which can induce differing adaptations. Here, we characterized the variation in the isokinetic parameters of knee extensors according to individualized angular velocity (IAV).
Methods: We performed a cross-sectional study of 19 young, healthy men. We measured the maximum angular velocity (MAV) of concentric knee extension using the isotonic mode of an isokinetic dynamometer. Isometric and isokinetic (at angular velocities corresponding to 100%, 70%, 40%, and 10% of each individual's MAV) knee extensor contractions were performed, and the peak torque and mean power were recorded.
Results: Peak torque significantly decreased with increasing IAV (129.42 ± 25.04, 84.37 ± 20.97, and 56.42 ± 16.18 Nm at 40%, 70%, and 100%, respectively), except for isometric contraction (233.36 ± 47.85) and at 10% of MAV (208 ± 48.55). At the mean power, 10% of MAV (74.52 ± 20.84 W) was significantly lower than the faster IAV (176.32 ± 49.64, 161.53 ± 56.55, and 145.95 ± 50.64 W at 40%, 70%, and 100%, respectively), and 100% was significantly lower than 40%.
Conclusion: The optimized IAV for isokinetic contraction to improve power output while maintaining torque is 10% to 40% of MAV. IAV may reflect both the velocity and force components of power because individuals do not have the same angular velocity.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11283666 | PMC |
http://dx.doi.org/10.1177/03000605241262186 | DOI Listing |
J Electromyogr Kinesiol
January 2025
Centro Polifunzionale di Scienze Motorie, Università degli Studi di Genova, Genoa, Italy; Department of Experimental Medicine, Section of Human Physiology, Università degli Studi di Genova, Genoa, Italy.
This study investigated proprioceptive acuity using the conventional joint position reproduction (JPR) task and a modified version, the Dynamic JPR task (D-JPR), during Concentric and Eccentric muscle contractions. Seventeen participants were recruited and received a tactile stimulus indicating the position cue at Initial (INI), Intermediate (INT), and Final (FIN) phases of movements, during either the concentric or eccentric phases. After the movement, they replicated the position where they received the stimulus.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra, Mexico City 14389, Mexico.
Portable monitoring devices based on Inertial Measurement Units (IMUs) have the potential to serve as quantitative assessments of human movement. This article proposes a new method to identify the optimal placements of the IMUs and quantify the smoothness of the gait. First, it identifies gait events: foot-strike (FS) and foot-off (FO).
View Article and Find Full Text PDFJ Clin Med
January 2025
Balance & Dizziness Center, Department of Otorhinolaryngology, Head & Neck Surgery and Audiology, Aalborg University Hospital, 9000 Aalborg, Denmark.
Accurate head positioning is essential for diagnostics of benign paroxysmal positional vertigo (BPPV). This study aimed to quantify the head angles and angular velocities during traditional manual BPPV diagnostics in patients with positional vertigo. : A prospective, observational cohort study was conducted at a tertiary university hospital outpatient clinic.
View Article and Find Full Text PDFJ Orthop Surg Res
January 2025
Medical College, Tibet University, Lhasa, Tibet, 850000, China.
Background: Knee osteoarthritis (KOA) is a prevalent degenerative joint disease. The primary pathological manifestations of KOA include articular cartilage degeneration, joint space narrowing, and osteophyte formation, leading to a spectrum of symptoms, including joint pain, stiffness, reduced mobility, diminished muscle strength, and severe disability. We aimed to utilize a meta-analysis to evaluate the efficacy of isokinetic muscle strengthening training (IMST) as a rehabilitation treatment for KOA in lowland areas.
View Article and Find Full Text PDFBioengineering (Basel)
January 2025
Department of Intelligent Robotics, Sungkyunkwan University, Suwon 16419, Republic of Korea.
Rehabilitation of gait function in post-stroke hemiplegic patients is critical for improving mobility and quality of life, requiring a comprehensive understanding of individual gait patterns. Previous studies on gait analysis using unsupervised clustering often involve manual feature extraction, which introduces limitations such as low accuracy, low consistency, and potential bias due to human intervention. This cross-sectional study aimed to identify and cluster gait patterns using an end-to-end deep learning approach that autonomously extracts features from joint angle trajectories for a gait cycle, minimizing human intervention.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!