ArticleEuropean journal of applied physiology2021
Fatigue-induced changes in knee-extensor torque complexity and muscle metabolic rate are dependent on joint angle.
Article in European journal of applied physiology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 2 of them syntheses that pooled it.
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Who cites it
15 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Pooled it
- The use of non-linear tools to analyze the variability of force production as an index of fatigue: A systematic review.Frontiers in physiology · 2022Pooled it
- Article
- Quadriceps Muscle Length Differentially Affects Exercise Capacity, the Torque-Duration Relationship, and Neuromuscular Fatigue.Scandinavian journal of medicine & science in sports · 2026Article
- Effects of Knee Joint Angle on Intramuscular Blood Flow and Muscle Deoxygenation During Fatiguing Isometric Contractions.Scandinavian journal of medicine & science in sports · 2026Article
- Force fluctuations regulation and the role of neurophysiological mechanisms throughout different isometric contraction intensities.Scientific reports · 2025Article
- Changes in torque complexity with fatigue are related to motor unit behaviour.Scientific reports · 2025Article
- Reduced rate of force development under fatigued conditions is associated to the decline in force complexity in adult males.European journal of applied physiology · 2024Article
- The interaction of post-activation potentiation and fatigue on skeletal muscle twitch torque and displacement.Frontiers in physiology · 2024Article
- Torque Regulation Is Influenced by the Nature of the Isometric Contraction.Sensors (Basel, Switzerland) · 2023Article
- Prolonged static stretching increases the magnitude and decreases the complexity of knee extensor muscle force fluctuations.PloS one · 2023Article
- The Effect of Breaking Up Sedentary Time with Calisthenics on Neuromuscular Function: A Preliminary Study.International journal of environmental research and public health · 2022Article
- Aging and skeletal muscle force control: Current perspectives and future directions.Scandinavian journal of medicine & science in sports · 2022Review
- Hip and Knee Joint Angles Determine Fatigue Onset during Quadriceps Neuromuscular Electrical Stimulation.Applied bionics and biomechanics · 2022Article
- Men exhibit faster skeletal muscle tissue desaturation than women before and after a fatiguing handgrip.European journal of applied physiology · 2021Article
Corrections and comments
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Authors and funding
3 authors.
Funding
Abstract
purposeJoint angle is a significant determinant of neuromuscular and metabolic function. We tested the hypothesis that previously reported correlations between knee-extensor torque complexity and metabolic rate ([Formula: see text]) would be conserved at reduced joint angles (i.e. shorter muscle lengths).
methodsEleven participants performed intermittent isometric knee-extensor contractions at 50% maximum voluntary torque for 30 min or until task failure (whichever occurred sooner) at joint angles of 30º, 60º and 90º of flexion (0º = extension). Torque and surface EMG were sampled continuously. Complexity and fractal scaling of torque were quantified using approximate entropy (ApEn) and detrended fluctuation analysis (DFA) α. [Formula: see text] was determined using near-infrared spectroscopy.
resultsTime to task failure/end increased as joint angle decreased (P < 0.001). Over time, complexity decreased at 90º and 60º (decreased ApEn, increased DFA α, both P < 0.001), but not 30º. [Formula: see text] increased at all joint angles (P < 0.001), though the magnitude of this increase was lower at 30º compared to 60º and 90º (both P < 0.01). There were significant correlations between torque complexity and [Formula: see text] at 90º (ApEn, r = - 0.60, P = 0.049) and 60º (ApEn, r = - 0.64, P = 0.035; DFA α, ρ = 0.68, P = 0.015).
conclusionThe lack of correlation between [Formula: see text] and complexity at 30º was likely due to low relative task demands, given the similar kinetics of [Formula: see text] and torque complexity. An inverse correlation between [Formula: see text] and knee-extensor torque complexity occurs during high-intensity contractions at intermediate, but not short, muscle lengths.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.