Abstract:
:The interrelationship between muscle strength, motor unit (MU) number, and age is poorly understood, and in this study we sought to determine whether age-related differences in muscle strength are moderated by estimates of functioning MU number and size. Eighteen older adults (OA; 67 ± 1.20 years) and 24 young adults (YA; 22 ± 0.74 years) participated in this study. Maximum voluntary pinch-grip strength of the nondominant hand was determined and estimates of MU number were obtained from the abductor pollicis brevis muscle using the noninvasive motor unit number index (MUNIX) technique. The MUNIX technique was also utilized to derive a motor unit size index (MUSIX). An analysis of covariance (Age Group × MUNIX or MUSIX) was used to test heterogeneity of regression slopes, with body mass and gender serving as covariates. We observed that the slope of pinch-grip strength on the estimated number of MUs between YA and OA differed, indicated by an Age Group × MUNIX interaction (p = 0.04). Specifically, after controlling for the effect of body mass and gender, the slope in OA was significantly positive (0.14 ± 0.06 N/MUs, p = 0.03), whereas no such relationship was found in YA (-0.08 ± 0.09 N/MUs, p = 0.35). A significant Age Group × MUSIX interaction was also observed for strength (p < 0.01). In contrast to MUNIX, the slope in younger adults was significantly positive (0.48 ± 0.11 N/μV, p < 0.01), whereas no such relationship was found in older adults (-0.30 ± 0.22 N/μV, p = 0.18). These findings indicate that there is an interrelationship between muscle strength, MU numbers, and aging, which suggests that a portion of muscle weakness in seniors may be attributable to the loss of functioning motor units.
journal_name
Exp Gerontoljournal_title
Experimental gerontologyauthors
Kaya RD,Nakazawa M,Hoffman RL,Clark BCdoi
10.1016/j.exger.2013.06.008subject
Has Abstractpub_date
2013-09-01 00:00:00pages
920-5issue
9eissn
0531-5565issn
1873-6815pii
S0531-5565(13)00209-Xjournal_volume
48pub_type
杂志文章abstract::Telomeres are specialised structures located at the end of eukaryotic chromosomes, that get short during progressive cell divisions. Therefore, telomere may be an indicator of the mitotic history of a cell and it is also a determining factor for the residual cell life span. One mechanism, compensating for the telomere...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(03)00058-5
更新日期:2003-06-01 00:00:00
abstract::Long-lived recombinant inbred lines, some of which have mean and maximum life spans up to 70% longer than wild type, were used in these analyses. Longer life results from a slower exponential rate of increase in mortality. General motor activity decreases with chronological age in all genotypes; this decay in general ...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/0531-5565(88)90031-9
更新日期:1988-01-01 00:00:00
abstract::Heat shock proteins (HSP's) closely interact with 20S proteasome and have been shown to maintain catalytic activity, responsible for the prevention of protein aggregation. A decrease in both proteasome activity and heat shock proteins (HSP's) has been observed with age. We investigated whether life-long calorie restri...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2004.08.012
更新日期:2005-01-01 00:00:00
abstract::Aging-related changes to biological structures such as cardiovascular and musculoskeletal systems contribute to the development of comorbid conditions including cardiovascular disease and frailty, and ultimately lead to premature death. Although, frail older adults often demonstrate both cardiovascular and musculoskel...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/j.exger.2020.111220
更新日期:2021-03-01 00:00:00
abstract:BACKGROUND:Oxidative stress and inflammation may contribute to anabolic resistance in response to protein and exercise in older adults. We investigated whether consumption of montmorency cherry concentrate (MCC) increased anabolic sensitivity to protein ingestion and resistance exercise in healthy older men. METHODS:S...
journal_title:Experimental gerontology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.exger.2018.06.007
更新日期:2018-09-01 00:00:00
abstract:BACKGROUND:Several studies reported an association between concentrations of serum uric acid and cognitive function, but the evidence is contradictory. It is known that uric acid is associated with cardiovascular diseases, especially among women. Stratifying by sex and history of cardiovascular disease may clarify whet...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2016.04.017
更新日期:2016-08-01 00:00:00
abstract::Alzheimer's disease (AD) is a progressive neurodegenerative disorder with characteristic neuropathological features that are accompanied by inflammatory processes and release of pro-inflammatory cytokines. There is evidence that microglial cells are a key mediator of damage in AD. The microglial compartment may arise ...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2009.10.005
更新日期:2010-01-01 00:00:00
abstract::Neuroblastoma cells (N1E-115) were used as models of transient (T) and long-lasting (L) Ca++ channels. The whole cell version of the patch clamp technique was used to measure inward Ca++ currents, and the fluorescent indicator, Fura-2, was used to measure changes in intracellular Ca++. Cells were cultured and selected...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/0531-5565(90)90059-b
更新日期:1990-01-01 00:00:00
abstract:BACKGROUND:An intermission in the training routine, in which older adults refrain from regular structured exercise, may have deleterious effects on muscle performance and bioelectric phase angle (PhA), which is a predictive marker for cellular integrity. PURPOSE:To determine the effects of a 2-week detraining period o...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2020.111175
更新日期:2021-02-01 00:00:00
abstract::Osteoporosis is extremely frequent in post-menopausal women; nevertheless, osteoporosis in men is also a severe and frequently occurring but often underestimated disease. Increasing evidence links bone loss in male idiopathic osteoporosis and age related osteoporosis to osteoblast dysfunction rather than increased ost...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2014.05.014
更新日期:2014-09-01 00:00:00
abstract:OBJECTIVE:The contribution of the A3243G mutation in mitochondria DNA (mtDNA) to diabetes mellitus (DM) in Werner's syndrome (WS) was studied. PATIENTS AND METHOD:DNA samples from peripheral white blood cells (WBCs) originating from 24 Japanese WS patients aged 30-56 were used. For control, 239 subjects aged 15-95 wer...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(02)002090-7
更新日期:2003-03-01 00:00:00
abstract::Alterations in the hypothalamic-pituitary-gonadal axis in females determine the transition from regular to irregular reproductive cycles, with loss of fertility. Stimulation of noradrenergic neurons of the anteroventral periventricular neurons (AVPV) is essential for regular reproductive cycles. Therefore, we examined...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2015.10.003
更新日期:2015-12-01 00:00:00
abstract::We have isolated a senescence-specific clone (pSEN) from a cDNA library constructed from late passage WI-38 human diploid fibroblast that accounts for approximately 1% of the recombinants. Nucleotide sequence analysis of the partial cDNA clone has led to the identification of pSEN as elongation factor I alpha. Norther...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/0531-5565(89)90056-9
更新日期:1989-01-01 00:00:00
abstract::The effects of long-term treatment with both antioxidants and a program of behavioral enrichment were studied as part of a longitudinal investigation of cognitive aging in beagle dogs. Baseline performance on a battery of cognitive tests was used to assign 48 aged dogs (9-12 years) into four cognitively equivalent gro...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2004.01.007
更新日期:2004-05-01 00:00:00
abstract::A number of recent studies of aging in Drosophila, mice and dogs have shown an association between reduced body size and increased lifespan. It is unclear (a) whether such an association is a general feature of animal species; and (b) whether the association reflects an effect of body size on aging, or pleiotropic eff...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(02)00147-x
更新日期:2003-01-01 00:00:00
abstract::Using data from Germany, we examine if month of birth influences survival up to age 105. Since age reporting at the highest ages is notoriously unreliable we draw on age-validated information from a huge age validation project of 1487 alleged German semi-supercentenarians aged 105+. We use month of birth as an exogeno...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2005.07.012
更新日期:2005-10-01 00:00:00
abstract::Every organism must adapt and respond appropriately to the source of nutrients available in its environment. Different mechanisms and pathways are involved in detecting the intracellular and extracellular levels of macronutrients including amino acids. Detection of amino acids in food sources is provided by taste cell...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/j.exger.2018.11.021
更新日期:2019-01-01 00:00:00
abstract::The dependent elderly are widely considered to be at higher risk of nutritional problems. Suboptimal micronutrient intake might put the elderly, especially those living in nursing homes, at high risk of morbidity. So far, no public authority, except for the Israel Ministry of Health, has issued particular recommendati...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2016.09.009
更新日期:2016-11-01 00:00:00
abstract::In aging tissues the oxidative stress increases due to decreased activity of antioxidant enzymes and proteolysis increases due to decreased activity of aminotransferases, which can be modified by hormonal replacement therapy (HRT). The aim of the present study was to determine the effect of HRT on the activities of an...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2005.01.004
更新日期:2005-04-01 00:00:00
abstract::Ageing is highly complex, involving multiple mechanisms at different levels. Nevertheless, recent evidence suggests that several of the most important mechanisms are linked via endogenous stress-induced DNA damage caused by reactive oxygen species (ROS). Understanding how such damage contributes to age-related changes...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/s0531-5565(01)00111-5
更新日期:2001-07-01 00:00:00
abstract:OBJECTIVE:The aim of this study was to compare the effects of 12 weeks of traditional resistance training (TRT) or resistance training using Cluster-set (CS) on functional performance and physical fitness of postmenopausal and elderly women. METHODS:Participants (61.1 ± 4.9 years, body mass 64.5 ± 1.8 kg, height 155.7...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2020.111011
更新日期:2020-09-01 00:00:00
abstract::The long life spans and slow aging rates of birds relative to mammals are paradoxical in view of birds' high metabolic rates, body temperatures and blood glucose levels, all of which are predicted to be liabilities by current biochemical theories of aging. Available avian life-table data show that most birds undergo r...
journal_title:Experimental gerontology
pub_type: 杂志文章,评审
doi:10.1016/s0531-5565(00)00247-3
更新日期:2001-04-01 00:00:00
abstract::Aging is one of the most basic properties of living organisms. Abundant evidence supports the idea that cell senescence underlies organismal aging in higher mammals. Therefore, examining the molecular mechanisms that control cell and replicative senescence is of great interest for biology and medicine. Several discove...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2010.01.009
更新日期:2010-03-01 00:00:00
abstract::Dystrophin-deficiency causes cardiomyopathies and shortens the life expectancy of Duchenne and Becker muscular dystrophy patients. Restoring Dystrophin expression in the heart by gene transfer is a promising avenue to explore as a therapy. Truncated Dystrophin gene constructs have been engineered and shown to alleviat...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2013.10.015
更新日期:2014-01-01 00:00:00
abstract:OBJECTIVES:We explored the male-female health-survival paradox in the context of health expectancy (HE) at age 65 and thereafter, using three different morbidity measures and different severity cut-offs with and without adjustments for the share of nursing home residents. METHODS:HE at ages 65, 70, 75, 80, and 85 was ...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2020.111196
更新日期:2021-03-01 00:00:00
abstract::There is growing concern over the increasing instances of decline in cognitive abilities with aging in humans. The present study evaluated the benefits of the natural antioxidant, grape seed proanthocyanidin extract (GSPE) in treating the effects of age-related oxidative stress (OS) and accumulation of lipofuscin (LF)...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2011.08.006
更新日期:2011-11-01 00:00:00
abstract::To determine whether age-related differences in body weight loss in hyperthyroidism could be related to caloric intake, the body weight and food consumption of Fischer 344 male rats were monitored every other day for four weeks. Six-month-old (young) rats were compared to 16-month-old rats (intermediate age) and 25-mo...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/0531-5565(90)90006-n
更新日期:1990-01-01 00:00:00
abstract::Impaired tolerance to ischemia-reperfusion in older hearts may stem in part from alterations in purine catabolism, impacting on maintenance of energy state and protective signaling via extracellular adenosine. We characterized effects of aging on normoxic and post-ischemic purine metabolism in hearts from young (2-4 m...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2003.08.003
更新日期:2003-10-01 00:00:00
abstract::Long-term caloric restriction (CR) has been shown to extend maximum life span in laboratory rodents. We investigated the activities of gluconeogenic and transaminase enzymes in the livers of old and young mice fed either control or calorie-restricted diets. Livers were sampled 48 h after the last scheduled feeding tim...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/s0531-5565(02)00202-4
更新日期:2003-03-01 00:00:00
abstract::Changes associated with the age-related decline of physiological functions, and their relation with mortality rates, are thoroughly being investigated in the aging research field. We used the Mediterranean fruit fly Ceratitis capitata, largely studied by biodemographers, as a model for functional senescence studies. T...
journal_title:Experimental gerontology
pub_type: 杂志文章
doi:10.1016/j.exger.2012.04.001
更新日期:2012-06-01 00:00:00