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Suprasinal Fatigue Impedes Recovery From A Low-Intensity Sustained Contraction In Old Adults, Tejin Yoon, Bonnie Schlinder-Delap, Manda Keller, Sandra Hunter
Suprasinal Fatigue Impedes Recovery From A Low-Intensity Sustained Contraction In Old Adults, Tejin Yoon, Bonnie Schlinder-Delap, Manda Keller, Sandra Hunter
Bonnie A Schlinder-Delap Mrs.
This study determined the contribution of supraspinal fatigue and contractile properties to the age difference in neuromuscular fatigue during and recovery from a low-intensity sustained contraction. Cortical stimulation was used to evoke measures of voluntary activation and muscle relaxation during and after a contraction sustained at 20% of maximal voluntary contraction (MVC) until task failure with elbow flexor muscles in 14 young adults (20.9 ± 3.6 years, 7 men) and 14 old adults (71.6 ± 5.4 years, 7 men). Old adults exhibited a longer time to task failure than the young adults (23.8 ± 9.0 min vs. 11.5 ± 3.9 …
Fatigability And Recovery Of Arm Muscles With Advanced Age For Dynamic And Isometric Contractions, Tejin Yoon, Bonnie Schlinder-Delap, Sandra K. Hunter
Fatigability And Recovery Of Arm Muscles With Advanced Age For Dynamic And Isometric Contractions, Tejin Yoon, Bonnie Schlinder-Delap, Sandra K. Hunter
Bonnie A Schlinder-Delap Mrs.
This study determined whether age-related mechanisms can increase fatigue of arm muscles during maximal velocity dynamic contractions, as it occurs in the lower limb. We compared elbow flexor fatigue of young (n = 10, 20.8 ± 2.7 years) and old men (n = 16, 73.8 ± 6.1 years) during and in recovery from a dynamic and an isometric postural fatiguing task. Each task was maintained until failure while supporting a load equivalent to 20% of maximal voluntary isometric contraction (MVIC) torque. Transcranial magnetic stimulation (TMS) was used to assess supraspinal fatigue (superimposed twitch, SIT) and muscle relaxation. Time to failure …
Supraspinal Fatigue Impedes Recovery From A Low-Intensity Sustained Contraction In Old Adults, Tejin Yoon, Bonnie Schlinder-Delap, Manda Keller, Sandra Hunter
Supraspinal Fatigue Impedes Recovery From A Low-Intensity Sustained Contraction In Old Adults, Tejin Yoon, Bonnie Schlinder-Delap, Manda Keller, Sandra Hunter
Bonnie A Schlinder-Delap Mrs.
This study determined the contribution of supraspinal fatigue and contractile properties to the age difference in neuromuscular fatigue during and recovery from a low-intensity sustained contraction. Cortical stimulation was used to evoke measures of voluntary activation and muscle relaxation during and after a contraction sustained at 20% of maximal voluntary contraction (MVC) until task failure with elbow flexor muscles in 14 young adults (20.9 ± 3.6 yr, 7 men) and 14 old adults (71.6 ± 5.4 yr, 7 men). Old adults exhibited a longer time to task failure than the young adults (23.8 ± 9.0 vs. 11.5 ± 3.9 min, …
Validity Of Boston Marathon Qualifying Times, Paul M. Vanderburgh
Validity Of Boston Marathon Qualifying Times, Paul M. Vanderburgh
Paul M. Vanderburgh
Purpose: To assess the validity of Boston Marathon qualifying (BMQ) standards for men and women. Methods: Percent differences between BMQ and current world records (WR) by sex and age group were computed. WR was chosen as the criterion comparison because it is not confounded by intensity, body composition, lifestyle, or environmental factors. A consistent difference across age groups would indicate an appropriate slope of the age-vs-BMQ curve. Inconsistent differences were corrected by adjusting BMQ standards to achieve a uniform percentage difference from WR. Results: BMQ standards for men were consistently ~50% slower than WR (mean 51.5% ± 1.4%, range 49.6–54.4%), …
Development Of A Clinical Multiple-Lunge Test To Predict Falls In Older Adults, Ruth Wagenaar, Justin W. Keogh, Denise Taylor
Development Of A Clinical Multiple-Lunge Test To Predict Falls In Older Adults, Ruth Wagenaar, Justin W. Keogh, Denise Taylor
Justin Keogh
Objective: To develop a new Multiple-Lunge Test to distinguish between fallers and nonfallers in community-dwelling older adults.Design: A cross-sectional design was used to establish the sensitivity and specificity of the test to predict faller status based on retrospective self-reported fall history. Setting: Local retirement villages.Participants: Community-dwelling older adults (N 130; mean age SD, 77 7y) with (n 40) and without (n 90) a history of falls.Interventions: The Multiple-Lunge Test required individuals to lunge forward to a step length determined as 60% of their leg length, and return to start, for 5 consecutive repetitions. Interday and intraday test-retest reliability of the …
Strength And Coordination Training Are Both Effective In Reducing The Postural Tremor Amplitude Of Older Adults, Justin W.L. Keogh, Steve Morrison, Rod Barrett
Strength And Coordination Training Are Both Effective In Reducing The Postural Tremor Amplitude Of Older Adults, Justin W.L. Keogh, Steve Morrison, Rod Barrett
Justin Keogh
The current study investigated the effect of 2 different types of unilateral resistance training on the postural tremor output of 19 neurologically healthy men age 70–80 yr. The strength- (n = 7) and coordination-training (n = 7) groups trained twice a week for 6 wk, performing dumbbell biceps curls, wrist flexions, and wrist extensions, while the control group (n = 5) maintained their normal activities. Changes in index-finger tremor (RMS amplitude, peak, and proportional power) and upper limb muscle coactivation were assessed during 4 postural conditions that were performed separately with the trained and untrained limbs. The 2 training groups …