Attenuated activation of knee extensor muscles during fast contractions in older men and women

Fatiguing exercise is the basis of exercise training and a cornerstone of management of type 2 diabetes mellitus (T2D); however, little is known about the fatigability of limb muscles and the involved mechanisms in people with T2D. The purpose of this study was to compare fatigability of knee extensor muscles between people with T2D and controls without diabetes and determine the neural and muscular mechanisms for a dynamic fatiguing task. Seventeen people with T2D [ten men and seven women: 59.6 (9.0) yr] and twenty-one age-, body mass index-, and physical activity-matched controls [eleven men and ten women: 59.5 (9.6) yr] performed one hundred twenty high-velocity concentric contractions (one contraction/3 s) with a load equivalent to 20% maximal voluntary isometric contraction (MVIC) torque with the knee extensors. Transcranial magnetic stimulation (TMS) and electrical stimulation of the quadriceps were used to assess voluntary activation and contractile properties. People with T2D had larger reductions than controls in power during the fatiguing task [42.8 (24.2) vs. 26.4 (15.0)%; P < 0.001] and MVIC torque after the fatiguing task [37.6 (18.2) vs. 26.4 (12.1)%; P = 0.04]. People with T2D had greater reductions than controls in the electrically evoked twitch amplitude after the fatiguing task [44.0 (20.4) vs. 35.4 (12.1)%, respectively; P = 0.01]. However, the decrease in voluntary activation was similar between groups when assessed with electrical stimulation [12.1 (2.6) vs. 12.4 (4.4)% decrease; P = 0.84] and TMS ( P = 0.995). A greater decline in MVIC torque was associated with larger reductions of twitch amplitude ( r2 = 0.364, P = 0.002). Although neural mechanisms contributed to fatigability, contractile mechanisms were responsible for the greater knee extensor fatigability in men and women with T2D compared with healthy controls. NEW & NOTEWORTHY Transcranial magnetic stimulation and percutaneous muscle stimulation were used to determine the contributions of neural and contractile mechanisms of fatigability of the knee extensor muscles after a dynamic fatiguing task in men and women with type 2 diabetes (T2D) and healthy age-, body mass index-, and physical activity-matched controls. Although neural and contractile mechanisms contributed to greater fatigability of people with T2D, fatigability was primarily associated with impaired contractile mechanisms and glycemic control.

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Alpha-Actinin-3 (ACTN3) R577X Polymorphism Influences Knee Extensor Peak Power Response to Strength Training in Older Men and Women

The Journals of Gerontology Series A ◽

10.1093/gerona/62.2.206 ◽

2007 ◽

Vol 62 (2) ◽

pp. 206-212 ◽

Cited By ~ 91

Author(s):

M. J. Delmonico ◽

M. C. Kostek ◽

N. A. Doldo ◽

B. D. Hand ◽

S. Walsh ◽

...

Keyword(s):

Strength Training ◽

Peak Power ◽

Knee Extensor ◽

Older Men ◽

Men And Women ◽

Power Response ◽

Older Men And Women

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Activation Of Knee Extensor Muscles During Rapid Force Development In Men And Women

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000517363.98226.cd ◽

2017 ◽

Vol 49 (5S) ◽

pp. 192

Author(s):

Minhyuk Kwon ◽

Jose D. Delgadillo ◽

Jonathon W. Senefeld ◽

Christopher W. Sundberg ◽

Sandra K. Hunter

Keyword(s):

Knee Extensor ◽

Men And Women ◽

Force Development ◽

Extensor Muscles ◽

Knee Extensor Muscles

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Knee extensor fatigue resistance of young and older men and women performing sustained and brief intermittent isometric contractions

Muscle & Nerve ◽

10.1002/mus.24174 ◽

2014 ◽

Vol 50 (3) ◽

pp. 393-400 ◽

Cited By ~ 14

Author(s):

Jamie S. Mcphee ◽

Thomas M. Maden-Wilkinson ◽

Marco V. Narici ◽

David A. Jones ◽

Hans Degens

Keyword(s):

Fatigue Resistance ◽

Knee Extensor ◽

Older Men ◽

Isometric Contractions ◽

Men And Women ◽

Older Men And Women

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The Case of Thematic Tests Adapted to Older Adults

Rorschachiana Journal of the International Society for the Rorschach ◽

10.1027/1192-5604/a000015 ◽

2011 ◽

Vol 32 (1) ◽

pp. 46-71 ◽

Cited By ~ 6

Author(s):

Benoît Verdon

Keyword(s):

Older Adults ◽

Older Persons ◽

Older Men ◽

Elderly Persons ◽

Mental Processes ◽

Men And Women ◽

Projective Tests ◽

New Material ◽

Older Men And Women ◽

Latent Content

Since the 1950s, the growing interest of clinicians in using projective tests to study normal or pathological aging processes has led to the creation of several thematic tests for older adults. This development reflects their authors’ belief that the TAT is not suitable to the concerns and anxieties of elderly persons. The new material thus refers explicitly to situations related to age; it aims to enable older persons to express needs they cannot verbalize during consultations. The psychodynamic approach to thematic testing is based on the differentiation between the pictures’ manifest and latent content, eliciting responses linked to mental processes and issues the respondent is unaware of. The cards do not necessarily have to show aging characters to elicit identification: The situations shown in the pictures are linked to loss, rivalry, helplessness, and renunciation, all issues elderly respondents can identify with and that lead them to express their mental fragilities and resources. The article first explains the principles underlying four of these thematic tests, then develops several examples of stories told for card 3BM of the TAT, thus showing the effectiveness of this tool for the understanding and differentiation of loss-related issues facing older men and women.

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Clyde Warrior, 1939–1968

Kalfou A Journal of Comparative and Relational Ethnic Studies ◽

10.15367/kf.v2i1.63 ◽

2015 ◽

Vol 2 (1) ◽

Author(s):

Tiffany Hale

Keyword(s):

Native Americans ◽

Older Men ◽

The United States ◽

Men And Women ◽

Student Nonviolent Coordinating Committee ◽

Political Struggles ◽

Poor People's Campaign ◽

Organizational Leader ◽

Martin Luther King ◽

Older Men And Women

To identify Clyde Warrior as an intellectual subverts prevailing notions of intellectualism. We often think of intellectuals as older men and women whose major contributions are revealed late in life, once the passions of youth have been tempered by experience. Warrior was not this. People frequently imagine intellectuals as existing in isolation, insulated from the demands of regular folk. Warrior was not this either. He was a Ponca, born on the reservation and raised with the influence of his grandparents and community. He was also a renowned singer and powwow fancy dancer, as well as a college student, an organizational leader, a husband, and father of two daughters. Warrior’s political consciousness grew out of the deep connections he maintained to his rural Ponca roots, but he took care to educate himself about the problems affecting Native Americans across the United States as well as colonized peoples globally. As an Oklahoman, he was attuned to race relations in the South and empathized with the struggles of Africans and African Americans. His approach to indigenous political struggles was shaped and informed, for example, by his early and active participation with the Student Nonviolent Coordinating Committee (SNCC) and Martin Luther King Jr.’s Poor People’s Campaign.

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