Acute effects of sustained isometric knee extension on cerebral and muscle oxygenation responses

This study aimed to examine the acute effects of fast-paced walking on isometric peak torque and rate of torque development (RTD) in regular exercising and inactive older women. Ten regular exercising (67 ± 4 years) and 10 inactive (68 ± 4 years) older women performed three isometric knee extension contractions before and after a control condition (quiet resting) and an experimental condition of fast-paced walking for 6 min. Peak torque and early (RTD100), late (RTD200), and maximum (peak RTD) RTD measurements were obtained from each contraction. Results showed no significant changes in peak torque, peak RTD, or RTD200 after walking for either group (p > .050). A significant decrease in RTD100 was observed after walking for the inactive group (p = .005) but not for the regular exercisers (p = .909). These findings highlight the importance of physical activity and suggest that a task as simple as walking may impair the rapid strength capacities of inactive older women.

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Running versus strength-based warm-up: acute effects on isometric knee extension function

European Journal of Applied Physiology ◽

10.1007/s00421-009-1047-0 ◽

2009 ◽

Vol 106 (4) ◽

pp. 573-581 ◽

Cited By ~ 14

Author(s):

Olivier Girard ◽

Yvan Carbonnel ◽

Robin Candau ◽

Grégoire Millet

Keyword(s):

Knee Extension ◽

Acute Effects ◽

Warm Up ◽

Strength Based ◽

Isometric Knee Extension

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Relationship between Muscle Oxygenation Kinetics and Tolerance to Fatigue on Short-term Isometric Knee Extension Exercise

The Journal of Japanese College of Angiology ◽

10.7133/jca.12-00014 ◽

2013 ◽

Vol 53 (July) ◽

pp. 93-98

Author(s):

Kaori Mitsuoka ◽

Ryotaro Kime ◽

Takuya Osada ◽

Norio Murase ◽

Toshihito Katsumura

Keyword(s):

Knee Extension ◽

Muscle Oxygenation ◽

Short Term ◽

Isometric Knee Extension ◽

Knee Extension Exercise

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A comparative study of the acute effects of knee brace vs. kinesiotape on selected isokinetic strength variables of the knee muscles

Isokinetics and Exercise Science ◽

10.3233/ies-200175 ◽

2021 ◽

pp. 1-6

Author(s):

Ali Kerim Yilmaz ◽

Mehmet Vural ◽

Mustafa Özdal ◽

Menderes Kabadayi

Keyword(s):

Knee Injuries ◽

Knee Extension ◽

Acute Effects ◽

Post Injury ◽

Kinesio Tape ◽

Knee Strength ◽

Significant Difference ◽

S Peak ◽

Male Subjects ◽

Methods Of Treatment

BACKGROUND: Different methods of treatment for preventing knee injuries, enhancing knee strength and minimising post-injury risks have been explored. Among these methods, Kinesio tape (KT) and knee braces (KB) are commonly used. OBJECTIVE : To investigate the acute effects of KT and KB on isokinetic knee strength parameters. METHODS: A total of 15 healthy sedentary male subjects voluntarily participated in the study. Concentric isokinetic knee extension (EX) and flexion (FLX) strength were measured at three sessions: 1. Baseline 2. with KT (’KT’) 3. with KB (’KB’). Tests were performed at 60, 180 and 240∘/s. Peak moment (PM), Hamstring/Quadriceps ratio (HQR), and joint angle at peak moment (JAPM) were measured. RESULTS: ‘KT’ and ‘KB’ were associated with increase in PMEX, PMFLX, HQR at 60 and 240∘/s (p< 0.05) and increased JAPMEX. No significant difference was observed at 180∘/s (p> 0.05). CONCLUSION: In healthy individuals, ‘I’ shape KT and KB positively affect EX and FLX strengths and HQR, especially at low angular velocity.

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EARLY STRENGTH TESTING AFTER ACL RECONSTRUCTION IMPACTS ISOKINETIC STRENGTH PERFORMANCE AT TIME OF RETURN TO SPORT

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121s00119 ◽

2021 ◽

Vol 9 (7_suppl3) ◽

pp. 2325967121S0011

Author(s):

Adam Weaver ◽

Dylan Roman ◽

Maua Mosha ◽

Nicholas Giampetruzzi

Keyword(s):

Test Performance ◽

Knee Extension ◽

Strength Test ◽

Strength Testing ◽

Isokinetic Strength ◽

Rehabilitation Process ◽

Strength Performance ◽

Knee Extension Strength ◽

Isometric Knee Extension ◽

Strength Tests

Background: The standard of care in ACL reconstruction (ACLR) typically involves standardized strength testing at 6 months or later to assess a patient’s readiness to return to play (RTP) using isokinetic and isometric testing, and functional strength testing. Recent literature suggests that isokinetic knee extension strength should demonstrate 89% limb symmetry index (LSI) or greater prior to returning to sport. However, there is little known on the effects of strength testing early in the rehabilitation process and the relationship to strength test performance at time of RTP. Purpose: The purpose of this study was to examine how early post-operative strength test performance impacts isokinetic strength outcomes at RTP testing in adolescents. Methods: The retrospective cohort study included patients undergoing primary ACLR between 12 and 18 years of age, early post-operative strength measures, and isokinetic dynamometer strength at RTP from July 2017 and April 2019. Data was dichotomized into desired outcomes at 3 months: >70% isometric knee extension LSI, > 20 repetitions on anterior stepdown test (AST), > 90% LSI Y Balance. At RTP testing, isokinetic knee extension strength data was categorized into >89% LSI at 3 speeds (300, 180, 60°/sec). Chi square testing and odds ratio statistics were used to examine association and its magnitude. Results: 63 patients met inclusion criteria (38 females; 15.37±1.66 years old). >70% LSI isometric knee extension strength at 3 months showed a significant association (Table 2) and demonstrated the strongest odds of having >89% LSI on isokinetic strength tests at all 3 speeds at RTP with 180°/sec being the highest (OR=14.5; 95% CI=4.25,49.43; p= <0.001). Performance on AST showed a significant association (χ2 (1, n=63) = 17.00, p <0.001), and highest odds at 180°/sec (OR=4.61; 95% CI = 1.59, 13.39, p=<0.001) and 60°/sec (OR= 3.07; 95% CI = 1.10, 8.63, p= 0.04). Combination of performance on isometric strength tests and AST showed a significant association to isokinetic strength at all three speeds, but less predictive then isometrics in isolation. (Table 2). There was no significant relationship between YBR LSI at 3 months and isokinetic strength at 6 months. Conclusion: Standardized strength testing early in rehabilitation can help identify patients that will successfully complete RTP testing. Our results suggest that isometric knee extension strength and timed anterior stepdown test provide meaningful clinical information early in the rehabilitation process. This data also suggests that the use of YBAL for predicting isokinetic strength performance is limited. [Table: see text][Table: see text]

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A Study on the Nonlinearity Relationship between Quadriceps Thickness and Torque Output during Isometric Knee Extension

Health Information Science - Lecture Notes in Computer Science ◽

10.1007/978-3-319-06269-3_6 ◽

2014 ◽

pp. 47-54

Author(s):

Xing Chen ◽

Xin Chen ◽

Jizhou Li ◽

Yongjin Zhou

Keyword(s):

Knee Extension ◽

Isometric Knee Extension

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Muscles Recruited During an Isometric Knee Extension is Defined by Proprioceptive Feedback

10.1101/802736 ◽

2019 ◽

Author(s):

Gareth York ◽

Hugh Osborne ◽

Piyanee Sriya ◽

Sarah Astill ◽

Marc de Kamps ◽

...

Keyword(s):

Spinal Cord ◽

Conflict Of Interest ◽

Rectus Femoris ◽

Knee Extension ◽

Proprioceptive Feedback ◽

Muscle Synergy ◽

Knee Angle ◽

Potential Conflict ◽

Dynamic Task ◽

Isometric Knee Extension

AbstractProprioceptive feedback and its role in control of isometric tasks is often overlooked. In this study recordings were made from upper leg muscles during an isometric knee extension task. Internal knee angle was fixed and subjects were asked to voluntarily activate their rectus femoris muscle. Muscle synergy analysis of these recordings identified canonical temporal patterns in the data. These synergies were found to encode two separate features: one concerning the coordinated contraction of the recorded muscles and the other indicating agonistic/antagonistic interactions between these muscles. The second synergy changed with internal knee angle reflecting the influence of afferent activity. This is in contrast to previous studies of dynamic task experiments which have indicated that proprioception has a negligible effect on synergy expression. Using the MIIND neural simulation platform, we developed a spinal population model with an adjustable input representing proprioceptive feedback. The model is based on existing spinal population circuits used for dynamic tasks. When the same synergy analysis was performed on the output from the model, qualitatively similar muscle synergy patterns were observed. These results suggest proprioceptive feedback is integrated in the spinal cord to control isometric tasks via muscle synergies.Significance statementSensory feedback from muscles is a significant factor in normal motor control. It is often assumed that instantaneous muscle stretch does not influence experiments where limbs are held in a fixed position. Here, we identified patterns of muscle activity during such tasks showing that this assumption should be revisited. We also developed a computational model to propose a possible mechanism, based on a network of populations of neurons, that could explain this phenomenon. The model is based on well established neural circuits in the spinal cord and fits closely other models used to simulate more dynamic tasks like locomotion in vertebrates.Conflict of interest statementThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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