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Full-Text Articles in Recreational Therapy
Mechanisms For The Age-Related Increase In Fatigability Of The Elbow Flexor Muscles In Healthy Adults, Blaine E. Arney, Andrew Kuplic, Mitchell D. Adam, Christopher W. Sundberg, Sandra Hunter
Mechanisms For The Age-Related Increase In Fatigability Of The Elbow Flexor Muscles In Healthy Adults, Blaine E. Arney, Andrew Kuplic, Mitchell D. Adam, Christopher W. Sundberg, Sandra Hunter
Exercise Science Faculty Research and Publications
The mechanisms for the age-related increase in fatigability of the elbow flexor muscles during dynamic contractions are unknown. The purpose of this study was to determine the contribution of supraspinal and contractile mechanisms for the age-related increase in fatigability of the elbow flexor muscles. Twenty-eight young (23.2 ± 2.6 years; 14 females) and 32 older adults (72.6 ± 5.6 years; 15 females) performed 80 maximal velocity contractions at 20% of maximal isometric strength. Voluntary activation and muscle contractile properties were assessed before and immediately following the fatiguing exercise using transcranial magnetic stimulation (TMS) and electrical stimulation. Fatigability (% reduction in …
Differential Effects Of Aging And Physical Activity On Corticospinal Excitability Of Upper And Lower Limb Muscles, Vianney Rozand, Jonathon William Senefeld, Christopher W. Sundberg, Ashleigh E. Smith, Sandra K. Hunter
Differential Effects Of Aging And Physical Activity On Corticospinal Excitability Of Upper And Lower Limb Muscles, Vianney Rozand, Jonathon William Senefeld, Christopher W. Sundberg, Ashleigh E. Smith, Sandra K. Hunter
Exercise Science Faculty Research and Publications
Corticospinal tract excitability can be altered by age, physical activity (PA), and possibly sex, but whether these effects differ between upper and lower limb muscles is unknown. We determined the influence of age, PA, and sex on corticospinal excitability of an upper limb and a lower limb muscle during submaximal contractions by comparing stimulus-response curves of motor evoked potentials (MEPs). Transcranial magnetic stimulation (TMS) was used to evoke stimulus-response curves in active muscles by incrementally increasing the stimulator intensity from below the active motor threshold (AMT) until a plateau in MEP amplitudes was achieved. Stimulus-response curves were analyzed from the …
Force Steadiness During A Cognitively Challenging Motor Task Is Predicted By Executive Function In Older Adults, Hugo M. Pereira, Bonnie A. Schlinder-Delap Mrs., Kristy A. Nielson, Sandra K. Hunter
Force Steadiness During A Cognitively Challenging Motor Task Is Predicted By Executive Function In Older Adults, Hugo M. Pereira, Bonnie A. Schlinder-Delap Mrs., Kristy A. Nielson, Sandra K. Hunter
Exercise Science Faculty Research and Publications
Motor performance and cognitive function both decline with aging. Older adults for example are usually less steady for a constant-force task than young adults when performing low-intensity contractions with limb muscles. Healthy older adults can also show varying degrees of cognitive decline, particularly in executive function skills. It is not known, however, whether age-related changes in steadiness of low-force tasks and cognitive function are independent of one another. In this study, we determined if executive function skills in aging are associated with the steadiness during a low-force muscle contraction performed with and without the imposition of a cognitive challenge. We …
Mechanisms For The Increased Fatigability Of The Lower Limb In People With Type 2 Diabetes, Jonathon Senefeld, Steven B. Magill, April L. Harkins, Alison R. Harmer, Sandra K. Hunter
Mechanisms For The Increased Fatigability Of The Lower Limb In People With Type 2 Diabetes, Jonathon Senefeld, Steven B. Magill, April L. Harkins, Alison R. Harmer, Sandra K. Hunter
Exercise Science Faculty Research and Publications
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 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 (10 men, 7 women: 59.6{plus minus}9.0 years) and 21 age-, BMI- and physical activity-matched controls (11 men, 10 women: 59.5{plus minus}9.6 years) performed 120 high-velocity concentric contractions (1 contraction/3 …
Contraction Intensity And Sex Differences In Knee-Extensor Fatigability, Paul Ansdell, Kevin Thomas, Glyn Howatson, Sandra K. Hunter, Stuart Goodall
Contraction Intensity And Sex Differences In Knee-Extensor Fatigability, Paul Ansdell, Kevin Thomas, Glyn Howatson, Sandra K. Hunter, Stuart Goodall
Exercise Science Faculty Research and Publications
Females are less fatigable than males during isometric contractions across various muscles and intensities. However, sex differences in knee-extensor fatigability remain relatively unexplored. Purpose: To determine the sex difference in performance fatigability for intermittent, isometric contractions of the knee-extensor muscles. Methods: Eighteen participants (10 males, 8 females) performed intermittent, isometric, knee-extensor contractions at 30% of their maximal voluntary force (MVC) for 30 min and in a separate session at 50% MVC until task-failure. During both fatiguing protocols a MVC was performed every 60 s and electromyography (EMG) was recorded during all contractions. Results: At task completion males had a larger …
Physical Activity Modulates Corticospinal Excitability Of The Lower Limb In Young And Old Adults, Hamidollah Hassanlouei, Christopher W. Sundberg, Ashleigh E. Smith, Andrew Kuplic, Sandra K. Hunter
Physical Activity Modulates Corticospinal Excitability Of The Lower Limb In Young And Old Adults, Hamidollah Hassanlouei, Christopher W. Sundberg, Ashleigh E. Smith, Andrew Kuplic, Sandra K. Hunter
Exercise Science Faculty Research and Publications
Aging is associated with reduced neuromuscular function, which may be due in part to altered corticospinal excitability. Regular physical activity (PA) may ameliorate these age-related declines, but the influence of PA on corticospinal excitability is unknown. The purpose of this study was to determine the influence of age, sex, and PA on corticospinal excitability by comparing the stimulus-response curves of motor evoked potentials (MEP) in 28 young (22.4 ± 2.2 yr; 14 women and 14 men) and 50 old adults (70.2 ± 6.1 yr; 22 women and 28 men) who varied in activity levels. Transcranial magnetic stimulation was used to …