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Sarcopenia, a skeletal muscle disorder that is characterised by loss of muscle strength and mass, is common in older populations and associated with poorer health outcomes. Although the individual and economic costs of sarcopenia are widely recognised, current understanding of its pathophysiology is incomplete, limiting efforts to translate research evidence into effective preventive and treatment strategies. While nutrition is a key field of sarcopenia research, the role of differences in habitual diets, and the effectiveness of dietary change as a prevention or treatment strategy, is uncertain. There is a growing evidence base that links low micronutrient intakes to sarcopenia risk and/or its components (low muscle strength and mass, impaired physical performance), although there remain many gaps in understanding. There is some consistency in findings across studies highlighting potential roles for antioxidant nutrients, B vitamins and magnesium; however, the evidence is largely observational and from cross-sectional studies, often describing associations with different muscle outcomes. As low intakes of some micronutrients are common in older populations, there is a need for new research, particularly from well-characterised prospective cohorts, to improve the understanding of their role and importance in the aetiology of sarcopenia and to generate the evidence needed to inform dietary guidelines to promote muscle health. [ABSTRACT FROM AUTHOR]

Sarcopenia is a progressive and generalized disease, more common in older adults, which manifests as a loss of muscle strength and mass. The pathophysiology of sarcopenia is still poorly understood with many mechanisms suggested. Age associated changes to the neuromuscular architecture, including motor units and their constituent muscle fibres, represent one such mechanism. Electromyography can be used to distinguish between different myopathies and produce counts of motor units. Evidence from electromyography studies suggests that with age, there is a loss of motor units, increases to the sizes of remaining units, and changes to their activity patterns. However, electromyography is invasive, can be uncomfortable, does not reveal the exact spatial position of motor units within muscle and is difficult to perform in deep muscles. We present a novel diffusion‐weighted magnetic resonance imaging technique called 'motor unit magnetic resonance imaging (MUMRI)'. MUMRI aims to improve our understanding of the changes to the neuromuscular system associated with ageing, sarcopenia and other neuromuscular diseases. To date, we have demonstrated that MUMRI can be used to detect statistically significant differences in fasciculation rate of motor units between (n = 4) patients with amyotrophic lateral sclerosis (mean age ± SD: 53 ± 15) and a group of (n = 4) healthy controls (38 ± 7). Patients had significantly higher rates of fasciculation compared with healthy controls (mean = 99.1/min, range = 25.7–161.0 in patients vs. 7.7/min, range = 4.3–9.7 in controls; P < 0.05. MUMRI has detected differences in size, shape, and distribution of single human motor units between (n = 5) young healthy volunteers (29 ± 2.2) and (n = 5) healthy older volunteers (65.6 ± 14.8). The maximum size of motor unit territories in the older group was 12.4 ± 3.3 mm and 9.7 ± 2.7 mm in the young group; P < 0.05. MUMRI is an entirely non‐invasive tool, which can be used to detect physiological and pathological changes to motor units in neuromuscular diseases. MUMRI also has the potential to be used as an intermediate outcome measure in sarcopenia trials. [ABSTRACT FROM AUTHOR]

Objective: To explore influences on diet in a group of community-dwelling older adults in the UK.Design: Data were collected through focus group discussions with older people; discussions were audio-recorded, transcribed verbatim and transcripts analysed thematically.Setting: Hertfordshire, UK.Subjects: Participants were sampled purposively from the Hertfordshire Cohort Study, focusing on those whose diets had been assessed at two time points: 1998-2001 and 2011.Results: Ninety-two adults participated (47 % women; 74-83 years) and eleven focus groups were held. A number of age-related factors were identified that were linked to food choices, including lifelong food experiences, retirement, bereavement and medical conditions, as well as environmental factors (such as transport). There appeared to be variability in how individuals responded to these influences, indicating that other underlying factors may mediate the effects of age-related factors on diet. Discussions about 'keeping going', being motivated to 'not give up', not wanting to be perceived as 'old', as well as examples of resilience and coping strategies, suggest the importance of mediating psychological factors. In addition, discussion about social activities and isolation, community spirit and loneliness, indicated the importance of social engagement as an influence on diet.Conclusions: Interventions to promote healthier diets in older age should take account of underlying psychological and social factors that influence diet, which may mediate the effects of age-related factors. [ABSTRACT FROM AUTHOR]

Background: poor diet quality is common among older people, but little is known about influences on food choice, including the role of psychosocial factors at this age. Objective: to identify psychosocial correlates of diet quality in a community-dwelling population of men and women aged 59-73 years; to describe relationships with change in diet quality over 10 years. Design: Longitudinal cohort, Hertfordshire Cohort Study (HCS). Subjects: HCS participants assessed at baseline (1998-2003: 1,048 men, 862 women); 183 men and 189 women re-assessed in 2011. Methods: diet was assessed by administered food frequency questionnaire; diet scores were calculated to describe diet quality at baseline and follow-up. A range of psychosocial factors (social support, social network, participation in leisure activities, depression and anxiety, sense of control) were assessed by questionnaire. Results: at baseline, better diet quality was related to a range of social factors, including increased confiding/emotional social support (men and women), practical support (men) and a larger social network (women) (all P < 0.05). For both men and women, greater participation in social and cognitive leisure activities was related to better diet quality (P < 0.005). There were few associations between measured psychosocial factors at baseline and change in diet score over 10 years, in the follow-up sub-group. However, greater participation in leisure activities, especially cognitive activities, at baseline was associated with smaller declines in diet quality over the 10-year follow-up period for both men (P = 0.017) and women (P = 0.014). Conclusions: in community-dwelling older adults, a range of social factors, that includes greater participation in leisure activities, were associated with diets of better quality. [ABSTRACT FROM AUTHOR]

Sarcopenia and frailty are important conditions that become increasingly prevalent with age. Sarcopenia is the loss of muscle mass and function, and frailty can be defined as multi-system impairment associated with increased vulnerability to stressors. There is overlap between the two conditions, especially in terms of the physical aspects of the frailty phenotype: low grip strength, gait speed and muscle mass. These measures have been associated with a wide range of ageing outcomes and can be assessed in the clinical setting. In terms of intervention, there is evidence for the benefit of resistance exercise programmes, although these may not always be feasible. Considerable research into the use of medicines, both existing and new, as well as dietary supplements is ongoing. Finally in order to prevent or delay the development of these conditions, an additional approach is to consider aetiological factors operating across the life course. [ABSTRACT FROM AUTHOR]

Sarcopenia and frailty are important conditions that become increasingly prevalent with age. Sarcopenia is the loss of muscle mass and function, and frailty can be defined as multi-system impairment associated with increased vulnerability to stressors. There is overlap between the two conditions, especially in terms of the physical aspects of the frailty phenotype: low grip strength, gait speed and muscle mass. These measures have been associated with a wide range of ageing outcomes and can be assessed in the clinical setting. In terms of intervention, there is evidence for the benefit of resistance exercise programmes, although these may not always be feasible. Considerable research into the use of medicines, both existing and new, as well as dietary supplements is ongoing. Finally in order to prevent or delay the development of these conditions, an additional approach is to consider aetiological factors operating across the life course. [ABSTRACT FROM AUTHOR]

Proprioception, the sense of where one is in space, is essential for effective interaction with the environment. A lack of or reduction in proprioceptive acuity has been directly correlated with falls and with reduced functional independence in older people [1]. Proprioceptive losses have also been shown to negatively correlate with functional recovery post stroke [2] and play a significant role in other conditions such as Parkinson's disease [3]. However, despite its central importance to many geriatric syndromes, the clinical assessment of proprioception has remained remarkably static [4]. We look at approaches to the clinical assessment of proprioception, changes in proprioception across the life course, functional implications of proprioception in health and disease and the potential for targeted interventions in the future such as joint taping, and proprioception-specific rehabilitation and footwear. [ABSTRACT FROM AUTHOR]

Sarcopenia is the age-related loss of skeletal muscle mass and function. It is now recognised as a major clinical problem for older people and research in the area is expanding exponentially. One of the most important recent developments has been convergence in the operational definition of sarcopenia combining measures of muscle mass and strength or physical performance. This has been accompanied by considerable progress in understanding of pathogenesis from animal models of sarcopenia. Well-described risk factors include age, gender and levels of physical activity and this knowledge is now being translated into effective management strategies including resistance exercise with recent interest in the additional role of nutritional intervention. Sarcopenia is currently a major focus for drug discovery and development although there remains debate about the best primary outcome measure for trials, and various promising avenues to date have proved unsatisfactory. The concept of ‘new tricks for old drugs’ is, however, promising, for example, there is some evidence that the angiotensin-converting enzyme inhibitors may improve physical performance. Future directions will include a deeper understanding of the molecular and cellular mechanisms of sarcopenia and the application of a lifecourse approach to understanding aetiology as well as to informing the optimal timing of interventions. [ABSTRACT FROM PUBLISHER]

Background: chronological age is widely used as a marker of frailty in clinical practice. However there can be wide variation in frailty between individuals of a similar age. Grip strength is a powerful predictor of disability, morbidity and mortality which has been used in a number of frailty scores but not as a single marker of frailty. Objective: to investigate the potential of grip strength as a single marker of frailty in older people of similar chronological age. Design: cross-sectional study with prospective collection of mortality data. Setting: North Hertfordshire, UK. Subjects: 717 men and women, aged 64-74, born and still living in North Hertfordshire, who took part in a previous study to investigate the relationship between size at birth and ageing processes in later life. Methods: the number of significant associations between grip strength and the ageing markers was compared with numbers between chronological age and the ageing markers. Results: in men, lower grip strength correlated significantly with ten ageing markers compared to chronological age which was significantly associated with seven. In women, there were six significant relationships for grip compared to three for age. The greater number of relationships between grip strength and ageing markers was not explained by the association between grip strength and age, and remained after adjustment for adult size. Conclusions: grip strength was associated with more markers of frailty than chronological age within the narrow age range studied. Grip strength may prove a more useful single marker of frailty for older people of similar age than chronological age alone. Its validity in a clinical setting needs to be tested. [ABSTRACT FROM AUTHOR]

Ageing may be simply defined but is yet to be well understood. Research in this area is considered a priority, with the population growing older and increasing disability, morbidity and mortality predicted. There are many theories and ageing has been described from changes at the molecular level to characteristics of ageing populations. However, distinguishing cause from effect has proved problematic largely because the underlying reasons for ageing have not been understood. Progress has now been made and the central role for repair processes is increasingly accepted. A number of approaches to modifying ageing have been explored but the only reliable method to alter the rate remains diet restriction. Instituted after weaning, diet restriction slows ageing in a number of species and has an opposite effect when started in earlier life. There is now preliminary evidence that poor early growth is associated with increased human ageing and this is an important area for future research. [ABSTRACT FROM AUTHOR]

Much has been achieved by recent research to increase understanding of the links between nutrition and muscle health. Focusing on muscle strength as the key component of sarcopenia, the aim of this overview was to evaluate its links to nutrition, both to variation in habitual diets in older populations, as well as considering supplementation effects in trials. A main message from the reviewed studies is that while many provide suggestive evidence of benefits of higher nutrient intakes and diets of higher quality, findings are inconsistent, and data on muscle strength are often lacking. To assess the potential of optimising diets as a strategy to promote and maintain muscle strength, gaps in current evidence need to be addressed. These include the need for (i) better understanding of individual differences in responsiveness to dietary change, and the need for targeted nutritional support; (ii) clearer distinction between protective and therapeutic actions of diet; and (iii) definition of the role of dietary patterns and their influence on muscle strength, to allow effects of changes in food consumption to be evaluated—particularly when combined with physical activity. Development of this evidence is needed to enable translation into appropriate dietary recommendations for older populations. [ABSTRACT FROM AUTHOR]