Isometric knee extension test: A practical, repeatable, and suitable tool for lower-limb screening among institutionalized older adults

Ramp isometric contractions determine peak torque (PT) and neuromuscular activation (NA), and ballistic contractions can be used to evaluate rate of torque development (RTD) and electrical mechanical delay (EMD). The purposes of this study were to assess the number of sessions required to stabilize ramp and ballistic PT and to compare PT and NA between contractions in older adults. Thirty-five older men and women (age 63.7 ± 3.7 yr, body mass 64.3 ± 10.7 kg, height 159.2 ± 6.6 cm) performed 4 sessions of unilateral ramp and ballistic isometric knee extension, 48 hr apart. PT significantly increased (main time effectp< .05) from the first to the third session, with no further improvements thereafter. There was a trend toward higher PT in ballistic than in ramp contractions. No difference between contraction types on EMG values was observed. Therefore, the authors suggest that 3 familiarization sessions be performed to correctly assess PT. In addition, PT, NA, RTD, and EMD can be assessed with ballistic contraction in older adults.

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Impact of home-based squat training with two-depths on lower limb muscle parameters and physical functional tests in older adults

Scientific Reports ◽

10.1038/s41598-021-86030-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Akito Yoshiko ◽

Kohei Watanabe

Keyword(s):

Older Adults ◽

Physical Function ◽

Lower Limb ◽

Muscle Thickness ◽

Peak Torque ◽

Knee Extension ◽

Functional Tests ◽

Leg Press ◽

Home Based ◽

Deep Squat

AbstractThis study investigated the effect of home-based shallow and deep squat trainings on knee extension peak torque, muscle thickness, one-repetition maximum (1RM) leg press, and physical function in older individuals. Sixteen participants were randomly assigned to the shallow squat group (SS group; age, 71.0 ± 4.0 years) or deep squat group (DS group, age; 68.6 ± 3.6 years). Chairs of 40-cm height and chairs with a cushion of 20-cm height (60-cm in total) were used as the depth targets for squats, with participants instructed to sink until their hip touched the chair and cushion. Participants performed four sets of squats per day (35 repetitions per set), three days per week, for 12 weeks at their home. Knee extension peak torque, muscle thickness of quadriceps femoris (e.g., vastus lateralis, rectus femoris, and vastus intermedius), and physical function were measured at weeks 0 (baseline), 4, 8, and 12. Maximal isometric knee extension peak torque, muscle thickness, and walking speed did not change significantly over the 12-week training period in either group (P > 0.05). However, compared with the baseline, there was significant improvement in the results of 30-s sit-to-stand repetition tests after weeks 8 and 12 in both groups (P < 0.05). Additionally, 1RM leg press results were significantly improved after weeks 4 and 12 in the DS group, and weeks 4, 8, and 12 in the SS group (P < 0.05). Results indicate that home-based weight-bearing squat training improves lower limb function in older adults, as well as performance in physical functional tests related to activities of daily living. Moreover, such training benefits older adults regardless of whether squats are shallow or deep.

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Fish Protein Ingestion Induces Neural, but Not Muscular Adaptations, Following Resistance Training in Young Adults

Frontiers in Nutrition ◽

10.3389/fnut.2021.645747 ◽

2021 ◽

Vol 8 ◽

Author(s):

Kohei Watanabe ◽

Aleš Holobar ◽

Kenji Uchida ◽

Yukiko Mita

Keyword(s):

Older Adults ◽

Young Adults ◽

Resistance Training ◽

Motor Unit ◽

Muscle Mass ◽

Knee Extension ◽

Fish Protein ◽

Motor Unit Firing ◽

Isometric Knee Extension ◽

Protein Ingestion

Purpose: Nutritional supplementation in conjunction with exercise is of interest for the prevention or improvement of declines in motor performances in older adults. An understanding of the effects on both young and older adults contributes to its effective application. We investigated the effect of fish protein ingestion with resistance training on neural and muscular adaptations in young adults using interventions and assessments that have already been tested in older adults.Methods: Eighteen young adults underwent 8 weeks of isometric knee extension training. During the intervention, nine participants ingested 5 g of fish protein (n = 9, Alaska pollack protein, APP), and the other nine participants ingested casein as a control (n = 9, CAS) in addition to daily meals. Before, during, and after the intervention, the isometric knee extension force, lower extremity muscle mass, and motor unit firing pattern of knee extensor muscles were measured.Results: Maximum voluntary contraction (MVC) was significantly increased in both APP and CAS groups from 0 weeks to 4, 6, and 8 weeks of intervention (p < 0.001), but there were no significant differences between the groups (p = 0.546–0.931). Muscle mass was not significantly changed during the intervention in either group (p = 0.250–0.698). Significant changes in motor unit firing rates (p = 0.02 and 0.029 for motor units recruited at 20–40% of MVC and at 40–60%) were observed following the intervention in the APP but not CAS (p = 0.120–0.751) group.Conclusions: These results suggest that dietary fish protein ingestion changes motor unit adaptations following resistance training in young adults.

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Reliability of a New Portable Dynamometer for Assessing Hip and Lower Limb Strength

Applied Sciences ◽

10.3390/app11083391 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3391

Author(s):

Jan Marušič ◽

Goran Marković ◽

Nejc Šarabon

Keyword(s):

Lower Limb ◽

External Rotation ◽

Peak Torque ◽

Knee Extension ◽

Lower Limb Muscles ◽

Lower Limb Strength ◽

Flexion Extension ◽

Strength Tests ◽

Hip Abduction ◽

Maximal Peak

The purpose of this study was to evaluate intra- and inter-session reliability of the new, portable, and externally fixated dynamometer called MuscleBoard® for assessing the strength of hip and lower limb muscles. Hip abduction, adduction, flexion, extension, internal and external rotation, knee extension, ankle plantarflexion, and Nordic hamstring exercise strength were measured in three sessions (three sets of three repetitions for each test) on 24 healthy and recreationally active participants. Average and maximal value of normalized peak torque (Nm/kg) from three repetitions in each set and agonist:antagonist ratios (%) were statistically analyzed; the coefficient of variation and intra-class correlation coefficient (ICC2,k) were calculated to assess absolute and relative reliability, respectively. Overall, the results display high to excellent intra- and inter-session reliability with low to acceptable within-individual variation for average and maximal peak torques in all bilateral strength tests, while the reliability of unilateral strength tests was moderate to good. Our findings indicate that using the MuscleBoard® dynamometer can be a reliable device for assessing and monitoring bilateral and certain unilateral hip and lower limb muscle strength, while some unilateral strength tests require some refinement and more extensive familiarization.

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The effect of lower limb muscle fatigue on obstacle negotiation during walking in older adults

Gait & Posture ◽

10.1016/j.gaitpost.2012.09.004 ◽

2013 ◽

Vol 37 (4) ◽

pp. 506-510 ◽

Cited By ~ 16

Author(s):

Anna L. Hatton ◽

Jasmine C. Menant ◽

Stephen R. Lord ◽

Joanne C.M. Lo ◽

Daina L. Sturnieks

Keyword(s):

Older Adults ◽

Muscle Fatigue ◽

Lower Limb ◽

Lower Limb Muscle ◽

Limb Muscle

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Losing touch: age-related changes in plantar skin sensitivity, lower limb cutaneous reflex strength, and postural stability in older adults

Journal of Neurophysiology ◽

10.1152/jn.00339.2016 ◽

2016 ◽

Vol 116 (4) ◽

pp. 1848-1858 ◽

Cited By ~ 17

Author(s):

Ryan M. Peters ◽

Monica D. McKeown ◽

Mark G. Carpenter ◽

J. Timothy Inglis

Keyword(s):

Older Adults ◽

Lower Limb ◽

Postural Stability ◽

Tibialis Anterior ◽

Tibialis Anterior Muscle ◽

Quiet Standing ◽

Detection Thresholds ◽

Cutaneous Reflex ◽

Age Related ◽

Age Related Changes

Age-related changes in the density, morphology, and physiology of plantar cutaneous receptors negatively impact the quality and quantity of balance-relevant information arising from the foot soles. Plantar perceptual sensitivity declines with age and may predict postural instability; however, alteration in lower limb cutaneous reflex strength may also explain greater instability in older adults and has yet to be investigated. We replicated the age-related decline in sensitivity by assessing monofilament and vibrotactile (30 and 250 Hz) detection thresholds near the first metatarsal head bilaterally in healthy young and older adults. We additionally applied continuous 30- and 250-Hz vibration to drive mechanically evoked reflex responses in the tibialis anterior muscle, measured via surface electromyography. To investigate potential relationships between plantar sensitivity, cutaneous reflex strength, and postural stability, we performed posturography in subjects during quiet standing without vision. Anteroposterior and mediolateral postural stability decreased with age, and increases in postural sway amplitude and frequency were significantly correlated with increases in plantar detection thresholds. With 30-Hz vibration, cutaneous reflexes were observed in 95% of young adults but in only 53% of older adults, and reflex gain, coherence, and cumulant density at 30 Hz were lower in older adults. Reflexes were not observed with 250-Hz vibration, suggesting this high-frequency cutaneous input is filtered out by motoneurons innervating tibialis anterior. Our findings have important implications for assessing the risk of balance impairment in older adults.

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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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