Effects of Self-Selected Step Length and Trunk Position on Joint Kinetics in Highly Physically Fit Older Adults

2020 ◽  
Vol 36 (3) ◽  
pp. 156-162
Author(s):  
Rebecca L. Krupenevich ◽  
Ross H. Miller

The causes of age-related differences in lower-extremity joint moments and powers are unknown. The purpose of this study was to determine the effects of highly physically active older adults walking with (1) a step length similar to young adults and (2) an upright trunk posture, on hip and ankle joint kinetics. The authors hypothesized that, compared with their self-selected walking mechanics, older adults would exhibit decreased hip kinetics and increased ankle kinetics when prescribed a young adult step length, and would exhibit decreased hip extension moments when maintaining an upright trunk posture during walking. A total of 12 active older adults (67 [5] y) and 13 active young adults (21 [3] y) walked at 1.3 m/s. The older adults also walked at 1.3 m/s with step lengths prescribed from height-matched young adults and, in a separate condition, walked with an upright trunk. The older adults did not display larger ankle kinetics or smaller hip kinetics in either condition compared to walking with a self-selected step length. These findings indicate that step length and trunk position do not primarily contribute to age-related differences in kinetics in highly active older adults and should serve as a starting point for investigating alternative explanations.

Author(s):  
Dennis E. Anderson ◽  
Michael L. Madigan

Significant age differences in self-selected gait kinetics have been reported in the literature. These include reduced torque and power at the ankle and increased work at the hip in older adults as compared to young adults [1, 2]. The reasons for these differences are complex and not fully understood. It is possible older adults adapt their gait to a safer, more stable gait pattern [3]. However, differences in gait may also be due to age-related neuromuscular changes such as reduced muscle strength in older adults [4].


2014 ◽  
Vol 28 (3) ◽  
pp. 148-161 ◽  
Author(s):  
David Friedman ◽  
Ray Johnson

A cardinal feature of aging is a decline in episodic memory (EM). Nevertheless, there is evidence that some older adults may be able to “compensate” for failures in recollection-based processing by recruiting brain regions and cognitive processes not normally recruited by the young. We review the evidence suggesting that age-related declines in EM performance and recollection-related brain activity (left-parietal EM effect; LPEM) are due to altered processing at encoding. We describe results from our laboratory on differences in encoding- and retrieval-related activity between young and older adults. We then show that, relative to the young, in older adults brain activity at encoding is reduced over a brain region believed to be crucial for successful semantic elaboration in a 400–1,400-ms interval (left inferior prefrontal cortex, LIPFC; Johnson, Nessler, & Friedman, 2013 ; Nessler, Friedman, Johnson, & Bersick, 2007 ; Nessler, Johnson, Bersick, & Friedman, 2006 ). This reduced brain activity is associated with diminished subsequent recognition-memory performance and the LPEM at retrieval. We provide evidence for this premise by demonstrating that disrupting encoding-related processes during this 400–1,400-ms interval in young adults affords causal support for the hypothesis that the reduction over LIPFC during encoding produces the hallmarks of an age-related EM deficit: normal semantic retrieval at encoding, reduced subsequent episodic recognition accuracy, free recall, and the LPEM. Finally, we show that the reduced LPEM in young adults is associated with “additional” brain activity over similar brain areas as those activated when older adults show deficient retrieval. Hence, rather than supporting the compensation hypothesis, these data are more consistent with the scaffolding hypothesis, in which the recruitment of additional cognitive processes is an adaptive response across the life span in the face of momentary increases in task demand due to poorly-encoded episodic memories.


2004 ◽  
Vol 47 (1) ◽  
pp. 33-45 ◽  
Author(s):  
Stephanie K. Daniels ◽  
David M. Corey ◽  
Leslie D. Hadskey ◽  
Calli Legendre ◽  
Daniel H. Priestly ◽  
...  

Recent research has revealed differences between isolated and sequential swallowing in healthy young adults; however, the influence of normal aging on sequential swallowing has not been studied. Thus, the purpose of this investigation was to examine the effects of normal aging on deglutition during sequential straw drinking. Videofluoroscopic samples of two 10-s straw drinking trials were obtained for 20 healthy young men (age 29±3 years) and 18 healthy older men (age 69±7 years). Hyolaryngeal complex (HLC) movement patterns, leading edge of the bolus location at swallow onset, and occurrences of airway invasion were determined. Two HLC patterns were identified: (a) HLC lowering with the epiglottis returned to upright between swallows and (b) partially maintained HLC elevation with the epiglottis inverted between swallows. The bolus was frequently in the hypopharynx at swallow onset. Strong associations were identified between age and HLC pattern, age and leading edge of the bolus location, and HLC pattern and leading edge location. Laryngeal penetration was uncommon overall; however, it occurred more frequently in the older adults than in the young adults. A significant relation was identified between age and the average Penetration-Aspiration Scale score. Laryngeal penetration was associated with both HLC movement patterns and hypopharyngeal bolus location, particularly in older adults. Results indicate that subtle age-related differences are evident in healthy young and older adults with sequential straw drinking. These data suggest that specific inherent swallowing patterns may increase the risk of laryngeal penetration with normal aging.


2019 ◽  
Vol 5 (s2) ◽  
Author(s):  
Daniel Müller-Feldmeth ◽  
Katharina Ahnefeld ◽  
Adriana Hanulíková

AbstractWe used self-paced reading to examine whether stereotypical associations of verbs with women or men as prototypical agents (e.g. the craftsman knits a sweater) are activated during sentence processing in dementia patients and healthy older adults. Effects of stereotypical knowledge on language processing have frequently been observed in young adults, but little is known about age-related changes in the activation and integration of stereotypical information. While syntactic processing may remain intact, semantic capacities are often affected in dementia. Since inferences based on gender stereotypes draw on social and world knowledge, access to stereotype information may also be affected in dementia patients. Results from dementia patients (n = 9, average age 86.6) and healthy older adults (n = 14, average age 79.5) showed slower reading times and less accuracy in comprehension scores for dementia patients compared to the control group. While activation of stereotypical associations of verbs was visible in both groups, they differed with respect to the time-course of processing. The effect of stereotypes on comprehension accuracy was visible for healthy adults only. The evidence from reading times suggests that older adults with and without dementia engage stereotypical inferences during reading, which is in line with research on young adults.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e6051 ◽  
Author(s):  
Brooke Brady ◽  
Ian I. Kneebone ◽  
Nida Denson ◽  
Phoebe E. Bailey

The process model of emotion regulation (ER) is based on stages in the emotion generative process at which regulation may occur. This meta-analysis examines age-related differences in the subjective, behavioral, and physiological outcomes of instructed ER strategies that may be initiated after an emotional event has occurred; attentional deployment, cognitive change, and response modulation. Within-process strategy, stimulus type, and valence were also tested as potential moderators of the effect of age on ER. A systematic search of the literature identified 156 relevant comparisons from 11 studies. Few age-related differences were found. In our analysis of the subjective outcome of response modulation strategies, young adults used expressive enhancement successfully (g = 0.48), but not expressive suppression (g = 0.04). Response modulation strategies had a small positive effect among older adults, and enhancement vs suppression did not moderate this success (g = 0.31 and g = 0.10, respectively). Young adults effectively used response modulation to regulate subjective emotion in response to pictures (g = 0.41) but not films (g = 0.01). Older adults were able to regulate in response to both pictures (g = 0.26) and films (g = 0.11). Interestingly, both age groups effectively used detached reappraisal, but not positive reappraisal to regulate emotional behavior. We conclude that, in line with well-established theories of socioemotional aging, there is a lack of evidence for age differences in the effects of instructed ER strategies, with some moderators suggesting more consistent effectiveness for older compared to younger adults.


2017 ◽  
Author(s):  
Shruti Dave ◽  
Trevor A. Brothers ◽  
Matthew J. Traxler ◽  
Fernanda Ferreira ◽  
John M. Henderson ◽  
...  

Young adults show consistent neural benefits of predictable contexts when processing upcoming words, but these benefits are less clear-cut in older adults. Here we conduct two ERP experiments to examine whether aging uniquely affects neural correlates of prediction accuracy, as compared to contextual support independent of accuracy. In Experiment 1, readers were asked to predict sentence-final words and self-report prediction accuracy, allowing for separation of ERP effects of accurate prediction and contextual support. While N250 and N400 effects of accurate prediction were reduced in older readers, both temporal primacy and relative amplitudes of predictive compared to contextual processing were similar across age. In Experiment 2, participants read for comprehension without an overt prediction task and showed similar age-related declines in N400 amplitude across experiments. In both studies, older adults showed relatively larger frontal post-N400 positivities (PNPs) than young adults, suggesting age-graded differences in revision following unexpected items. Previous research suggests the production system may be linked to lexical prediction, but here we found that verbal fluency modulated PNP effects of contextual support, but not predictive accuracy. Taken together, our findings suggest that normative aging does not result in specific declines or boosts of lexical prediction.


2014 ◽  
Vol 30 (4) ◽  
pp. 542-546 ◽  
Author(s):  
Dennis E. Anderson ◽  
Christopher T. Franck ◽  
Michael L. Madigan

The effects of gait speed and step length on the required coefficient of friction (COF) confound the investigation of age-related differences in required COF. The goals of this study were to investigate whether age differences in required COF during self-selected gait persist when experimentally-controlling speed and step length, and to determine the independent effects of speed and step length on required COF. Ten young and 10 older healthy adults performed gait trials under five gait conditions: self-selected, slow and fast speeds without controlling step length, and slow and fast speeds while controlling step length. During self-selected gait, older adults walked with shorter step lengths and exhibited a lower required COF. Older adults also exhibited a lower required COF when walking at a controlled speed without controlling step length. When both age groups walked with the same speed and step length, no age difference in required COF was found. Thus, speed and step length can have a large influence on studies investigating age-related differences in required COF. It was also found that speed and step length have independent and opposite effects on required COF, with step length having a strong positive effect on required COF, and speed having a weaker negative effect.


2016 ◽  
Vol 5 (1) ◽  
pp. 30-38 ◽  
Author(s):  
Jennifer J. Heisz ◽  
Ana Kovacevic

Age-related changes in the brain can compromise cognitive function. However, in some cases, the brain is able to functionally reorganize to compensate for some of this loss. The present paper reviews the benefits of exercise on executive functions in older adults and discusses a potential mechanism through which exercise may change the way the brain processes information for better cognitive outcomes. Specifically, older adults who are more physically active demonstrate a shift toward local neural processing that is associated with better executive functions. We discuss the use of neural complexity as a sensitive measure of the neural network plasticity that is enhanced through exercise. We conclude by highlighting the future work needed to improve exercise prescriptions that help older adults maintain their cognitive and physical functions for longer into their lifespan.


2019 ◽  
Author(s):  
Meaghan Elizabeth Spedden ◽  
Mikkel Malling Beck ◽  
Mark Schram Christensen ◽  
Martin Jensen Dietz ◽  
Anke Ninija Karabanov ◽  
...  

AbstractThe control of ankle muscle force is an integral component of walking and postural control. Aging impairs the ability to produce force steadily and accurately, which can compromise functional capacity and quality of life. Here, we hypothesized that reduced force control in older adults would be associated with altered cortico-cortical communication within a network comprising the primary motor area (M1), the premotor cortex (PMC), parietal, and prefrontal regions. We examined electroencephalographic (EEG) responses from fifteen younger (20-26 yr) and fifteen older (65-73 yr) participants during a unilateral dorsiflexion force-tracing task. Dynamic Causal Modelling (DCM) and Parametric Empirical Bayes (PEB) were used to investigate how directed connectivity between contralateral M1, PMC, parietal, and prefrontal regions was related to age group and precision in force production. DCM and PEB analyses revealed that the strength of connections between PMC and M1 were related to ankle force precision and differed by age group. For young adults, bidirectional PMC-M1 coupling was negatively related to task performance: stronger backward M1-PMC and forward PMC-M1 coupling was associated with worse force precision. The older group exhibited deviations from this pattern. For the PMC to M1 coupling, there were no age-group differences in coupling strength; however, within the older group, stronger coupling was associated with better performance. For the M1 to PMC coupling, older adults followed the same pattern as young adults - with stronger coupling accompanied by worse performance - but coupling strength was lower than in the young group. Our results suggest that bidirectional M1-PMC communication is related to precision in ankle force production and that this relationship changes with aging. We argue that the observed age-related differences reflect compensatory mechanisms whereby older adults maintain performance in the face of declines in the sensorimotor system.


Author(s):  
Ernest K. Ofori ◽  
Savitha Subramaniam ◽  
Shuaijie Wang ◽  
Tanvi Bhatt

Background: Recent studies demonstrate improvements in both postural stability and mobility among aging populations and those with stroke who are exposed to dance-based exergaming (DBExG). However, age-related deficits and aging with cortical pathology may lead to distinct movement adaptation patterns during DBExG, which could impact therapeutic outcomes.Aim: The aim of this study was to examine the movement kinematics (postural stability and mobility) of healthy older adults, older adults with stroke, and young adults for different paces of dance during DBExG. Method: The study included 33 particpants (11 participant from each group of healthy older adults, older adults with chronic stroke, and healthy young adults) who performed the DBExG using slow- (SP), medium- (MP), and fast-paced (FP) songs with movements in the anteroposterior (AP) and mediolateral (ML) directions. Center of mass (CoM) sway area, excursion (Ex), and peaks as well as hip, knee, and ankle joint excursions were computed. Results: Results of the study revealed that CoM sway areas and Exs were greater for healthy young adults than for older adults with stroke for the SP dance (p < 0.05) and that there were significantly more AP CoM peaks for young adults than for healthy older adults and those with stroke for the FP dance (p < 0.05). Young adults also exhibited greater hip and ankle Exs than older adults with stroke (p < 0.05) for all song paces. Similarly, knee and ankle Exs were greater for healthy older adults than for older adults with stroke for all song paces (p < 0.05). Conclusion: The quantitative evaluation and comparison of the movement patterns presented for the three groups could provide a foundation for both assessing and designing therapeutic DBExG protocols for these populations.


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