Peak torque and rate of torque development in elderly with and without fall history

In explosive contractions, neural activation is a major factor in determining the rate of torque development, while the latter is an important determinant of jump performance. However, the contribution of neuromuscular activation and rate of torque development to jump performance in children and youth is unclear. The purpose of this study was to examine the relationships between the rate of neuromuscular activation, peak torque, rate of torque development, and jump performance in young male athletes. Forty-one 12.5 ± 0.5-year-old male soccer players completed explosive, unilateral isometric and dynamic (240°/s) knee extensions (Biodex System III), as well as countermovement-, squat-, and drop-jumps. Peak torque (pT), peak rate of torque development (pRTD), and rate of vastus lateralis activation (Q30) during the isometric and dynamic contractions were examined in relation to attained jump heights. Isometric pT and pRTD were strongly correlated (r = 0.71) but not related to jump performance. Dynamic pT and pRTD, normalized to body mass, were significantly related to jump height in all 3 jumps (r = 0.38–0.66, p < 0.05). Dynamic normalized, but not absolute pRTD, was significantly related to Q30 (r = 0.35, p < 0.05). In young soccer players, neuromuscular activation and rate of torque development in dynamic contractions are related to jump performance, while isometric contractions are not. These findings have implications in the choice of training and assessment methods for young athletes.

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Child–adult differences in muscle strength and activation pattern during isometric elbow flexion and extension

Applied Physiology Nutrition and Metabolism ◽

10.1139/h09-020 ◽

2009 ◽

Vol 34 (4) ◽

pp. 609-615 ◽

Cited By ~ 42

Author(s):

Bareket Falk ◽

Charlotte Usselman ◽

Raffy Dotan ◽

Laura Brunton ◽

Panagiota Klentrou ◽

...

Keyword(s):

Muscle Strength ◽

Muscle Activation ◽

Motor Units ◽

Elbow Flexion ◽

Peak Torque ◽

Electromechanical Delay ◽

Cross Sectional ◽

Rate Of Torque Development ◽

Torque Development ◽

Flexion And Extension

Muscle strength and activation were compared in boys and men during maximal voluntary elbow flexion and extension contractions. Peak torque, peak rate of torque development (dτ/dτmax), rate of muscle activation, and electromechanical delay (EMD) were measured in 15 boys (aged 9.7 ± 1.6 years) and 16 men (aged 22.1 ± 2.8 years). During flexion, peak torque was significantly lower in boys than in men (19.5 ± 5.8 vs. 68.5 ± 11.0 Nm, respectively; p < 0.05), even when controlling for upper-arm cross-sectional area (CSA), and peak electromyography activity. Boys also exhibited a lower normalized dτ/dτmax (7.2 ± 1.7 vs. 9.5 ± 1.6 (Nm·s–1)·(Nm–1), respectively; p < 0.05) and a significantly longer EMD (75.5 ± 28.4 vs. 47.6 ± 17.5 ms, respectively). The pattern was similar for extension, except that group differences in peak torque were no longer significant when normalized for CSA. These results suggest that children may be less able to recruit or fully utilize their higher-threshold motor units, resulting in lower dimensionally normalized maximal torque and rate of torque development.

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Effect of Aging on Trunk Muscle Function and Its Influence on Falls Among Older Adults

Journal of Aging and Physical Activity ◽

10.1123/japa.2019-0194 ◽

2020 ◽

Vol 28 (5) ◽

pp. 699-706

Author(s):

Jaqueline M. Porto ◽

Sállua B. Spilla ◽

Luciana M. Cangussu-Oliveira ◽

Renato C. Freire Júnior ◽

Ana Paula M. Nakaishi ◽

...

Keyword(s):

Older Adults ◽

Muscle Function ◽

Peak Torque ◽

Young Group ◽

Trunk Muscle ◽

Tukey Test ◽

Rate Of Torque Development ◽

Extensor Torque ◽

Post Hoc ◽

Torque Development

The objective was to determine whether trunk muscle function is influenced by the aging process and to identify if the trunk can be an important factor in older people’s falls over a period of 1 year. The peak torque, rate of torque development, and torque steadiness of the trunk extensors and flexors were compared between a young group, older group (older adults with no episodes of falls), and older faller group (older adults who had suffered at least one fall episode over a period of 1 year) by one-way analysis of variance, followed by the post hoc Tukey test. The adjusted multivariate linear regression was applied to verify the association between the number of falls and the trunk parameters in older adults. The young group showed higher extensors and flexors peak torque and rate of torque development, and lower extensor torque steadiness at 10% when compared with older groups. Only trunk flexor peak torque showed a negative association with the number of future falls (p = .042), but there was no difference in trunk muscle function between the older group and the older faller group.

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Passive Stiffness and Maximal and Explosive Strength Responses After an Acute Bout of Constant-Tension Stretching

Journal of Athletic Training ◽

10.4085/1062-6050-62-18 ◽

2019 ◽

Vol 54 (5) ◽

pp. 519-526 ◽

Cited By ~ 1

Author(s):

Ty B. Palmer ◽

Ryan M. Thiele

Keyword(s):

Time Course ◽

Outcome Measurement ◽

Peak Torque ◽

Passive Stiffness ◽

Explosive Strength ◽

Rate Of Torque Development ◽

Short Bout ◽

Constant Tension ◽

Before And After ◽

Torque Development

Context Constant-tension (CT) stretching has been used to reduce hamstrings passive stiffness; however, the time course of hamstrings stiffness responses during a short bout of this type of stretching and the effects on maximal and explosive strength remain unclear. Objective To examine the time course of hamstrings passive-stiffness responses during a short, practical bout of manual straight-legged–raise (SLR) CT passive stretches and their effects on maximal and explosive strength in healthy young women. Design Descriptive laboratory study. Setting Research laboratory. Patients or Other Participants Eleven healthy women (age = 24 ± 4 years, height = 167 ± 4 cm, mass = 65 ± 8 kg) participated. Intervention(s) Participants underwent four 15-second SLR CT passive stretches of the hamstrings. Main Outcome Measurement(s) Hamstrings passive stiffness was calculated from the slopes of the initial (phase 1) and final (phase 2) portions of the angle-torque curves generated before and after the stretching intervention and at the beginning of each 15-second stretch. Hamstrings peak torque and rate of torque development were derived from maximal voluntary isometric contractions performed before and after the stretching intervention. Results The slope coefficients (collapsed across phase) for the third and fourth stretches and the poststretching assessment were lower than the prestretching assessment (P range = .004–.04), but they were not different from each other (P > .99). In addition, no differences in peak torque (t10 = −0.375, P = .72) or rate of torque development (t10 = −0.423, P = .68) were observed between prestretching and poststretching. Conclusions A short bout of SLR CT passive stretching may effectively reduce hamstrings stiffness without negatively influencing maximal and explosive strength.

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Effects of Warm-up on Peak Torque, Rate of Torque Development, and Electromyographic and Mechanomyographic Signals

The Journal of Strength and Conditioning Research ◽

10.1519/jsc.0b013e31822e7a85 ◽

2012 ◽

Vol 26 (5) ◽

pp. 1296-1301 ◽

Cited By ~ 5

Author(s):

Kristianna M. Altamirano ◽

Jared W. Coburn ◽

Lee E. Brown ◽

Daniel A. Judelson

Keyword(s):

Peak Torque ◽

Warm Up ◽

Rate Of Torque Development ◽

Torque Development

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Muscle Strength and Contractile Kinetics of Isometric Elbow Flexion in Girls and Women

Pediatric Exercise Science ◽

10.1123/pes.21.3.354 ◽

2009 ◽

Vol 21 (3) ◽

pp. 354-364 ◽

Cited By ~ 13

Author(s):

Bareket Falk ◽

Laura Brunton ◽

Raffy Dotan ◽

Charlotte Usselman ◽

Panagiota Klentrou ◽

...

Keyword(s):

Statistical Significance ◽

Elbow Flexion ◽

Peak Torque ◽

Muscle Size ◽

Cross Sectional ◽

Time To Peak ◽

Peak Rate ◽

Rate Of Torque Development ◽

Age Related ◽

Torque Development

Ten prepubertal girls and 15 young women were tested for maximal torque, peak rate of torque development, electro-mechanical delay (EMD), and time to peak rate of torque development during isometric elbow flexion. Absolute peak torque (17.0 ± 7.7 vs. 40.5 ± 8.3 Nm) and peak rate of torque development (105.9 ± 58.6 vs. 297.2 ± 113.0 Nm·s−1) were lower in the girls (p < .05). Normalized to muscle cross sectional area, torque was similar (8.27 ± 2.74 vs. 8.44 ± 1.65 Nm·cm−2), as was peak rate of torque development, normalized to peak torque (6.21 ± 1.94 vs. 7.30 ± 2.26 Nm·s−1/Nm). Both, time to peak rate of torque development (123.8 ± 36.0 vs. 110.5 ± 52.6 ms) and EMD (73.2 ± 28.6 vs. 51.9 ± 25.6 ms), were longer in the girls, although EMD’s difference only approached statistical significance (p = .06). Age-related isometric strength differences in females appear to be mainly muscle-size dependent. However, the time to peak torque and EMD findings suggest differential motor-unit activation which may functionally manifest itself in fast dynamic contractions.

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