Physical frailty in old age largely stems from sarcopenia – the loss of skeletal muscle strength and mass – but a new series of clinical studies has shed light on its causation, and led to recommendations to help combat it. The research will be presented today [26 July 2013] as part of the 37th International Union of Physiological Sciences (IUPS) congress, in Birmingham.
In older age, protein malnutrition becomes more common while at the same time muscles can become ‘desensitized’ to the benefits of dietary protein and activity. Sedentary behaviour, as a result of sarcopenia, can lead to health problems (as muscles play a role in blood sugar levels and other key metabolic functions), social isolation, depression and generally a poorer quality-of-life. Therefore finding ways to enhance the effects of nutrition and exercise in old age is paramount.
Research undertaken over the past few years at The University of Nottingham has uncovered novel features of ageing muscle, which form the basis for determining potential strategies by which to mitigate sarcopenia.
Dr Philip Atherton, University of Nottingham, explains a few basic recommendations that address improving health outcomes in the face of our increasingly ageing demographic, “Firstly, it is important to ensure sufficient habitual activity since immobility and even reducing the number of steps we walk each day can cause adverse metabolic changes and muscle loss.
“Secondly, resistance exercise (for example, lifting weights) is particularly useful for maintaining muscle, especially when coupled to strategies aimed at heightening exercise-associated “metabolic stress” i.e., increasing exercise volume.
“Finally, small amounts of protein should be consumed regularly (every ~4-6 h) and alongside bouts of activity. In particular, dietary proteins rich in the amino acid leucine (amino acids form the building blocks of protein) are very effective for maximizing the beneficial effects of exercise, in older age.”
The clinical studies in humans used new research tools and specialized approaches involving blood sampling, muscle biopsies and the trickling of amino acid ‘tracers’ into volunteer’s veins to measure the processes involved in the building-up and breaking-down of skeletal muscle.
Dr Atherton explains the wider economic and social importance of tackling this issue: “Our society has an increasingly ageing population due to the ‘baby boom’ of the 1960’s and increased lifespan, courtesy of improved healthcare and better nutrition. Unfortunately though, maintaining good-health into older age has not kept pace with increases in longevity. This has had major economical and social implications. The cost to the NHS for retired households is twice that of non-retired households and for those aged >85 y, the cost is three-fold higher.
“This research is essential to generate targeted interventions aimed at reducing the socio-economic consequences associated with physical frailty in human older age.”
Dr Atherton explains the next steps in the field: “We intend to use a new tracer called ‘heavy water’ to determine how ageing impacts on the muscle’s own ‘stem cells’ (satellite cells) that are necessary to maintain mass, and also to monitor how and why muscles get more fatty with age and what we might be able to do about it.”
Notes for Editors
1. Dr Atherton’s lecture at the IUPS Congress in Birmingham (The ICC):
Metabolic and molecular regulation of skeletal muscle in older age
Friday 26 July 2013, 10.00 – 10.15, Hall 1
2. Congress of the International Union of Physiological Sciences (IUPS), 22-26 July, Birmingham
The congress will bring together over 3000 physiologists from all corners of the globe to attend over 100 symposia and 30 keynote lectures. The congress has been running since 1889 and was started in an effort to promote physiology, encourage the interchange of ideas, and afford physiologists the opportunity to know one another personally. www.iups2013.org
Dr Phil Atherton, University of Nottingham
Tel (office): +44 (0) 1332 724725
Tel (mobile): +44 (0) 7590 724410
Ms. Tanya Fletcher, Divisional PA
Tel: +44 (0) 1332 724668
Fax: +44 (0) 1332 724697
The Physiological Society (hosts of IUPS 2013):
Lucy Holmes, Media and Communications Officer
+44 (0)20 7269 5727, +44 (0)7917 610 731, email@example.com