Muscle mass, quality, and the menopause: sex-specific strategies to mitigate sarcopenia in aging populations
Lead Research Organisation:
University of Nottingham
Department Name: School of Life Sciences
Abstract
As we grow older, our muscles become smaller and weaker (sarcopenia), which can make it more difficult to complete daily activities and can increase our reliance on healthcare systems. The UK has a growing ageing population, and, therefore, sarcopenia represents a major healthcare concern, (for example, its estimated cost to the UK healthcare system in 2016 was £2.5 billion). There is an urgent need to develop strategies to prevent sarcopenia. However, these strategies need to be targeted, with evidence suggesting that older men and women develop sarcopenia differently. For instance, sarcopenia develops earlier in women, resulting in greater levels of physical disability compared with men. The underlying sex differences with ageing are unclear, yet the earlier prevalence of sarcopenia in women coincides with the menopause. The menopause is a change in the sex hormone environment that is a part of normal female ageing and is associated with changes in body composition including muscle loss and increased body fat. This increase in body fat can become located within muscle, further accelerating the loss of muscle strength and poor health.
There is a lack of understanding of how these changes in body composition occur. However, for muscle to decrease in size, there must be an imbalance between how quickly we remove muscle proteins and how quickly we make new muscle proteins. We have recently developed advanced biochemistry techniques to measure how quickly we make and remove muscle proteins. By applying these techniques to pre- and post-menopausal women, we will be able to better understand muscle protein balance during ageing for the first time. By combining these techniques with magnetic resonance imaging (MRI), we will develop new methods to locate where, and how quickly, new fat is deposited in the body. Combined, these approaches will provide vital insights on how best to target future interventions against sarcopenia in women.
Resistance exercise therapy (RET) currently offers the most effective strategy to promote muscle mass and strength in ageing. However, responses to resistance exercise are blunted in older women compared to younger women. We will measure whether the menopause has an impact on how quickly new muscle proteins are made in response to exercise, and, using our MRI imaging techniques, we will monitor whether RET alters the rate of fat deposition in the body. Together, these measures will determine the effectiveness of RET at slowing sarcopenia and improving body composition in post-menopausal women. Using our results, we will create evidence-based resources and information, and implement these recommendations into menopause intervention programmes through existing connections with Sport England Active Partnerships (Active Together in Leicestershire and Sport Notts), Sports Exercise Medicine departments at the Universities of Nottingham and Leicester and the National Centre for Sport and Exercise Medicine in Loughborough, as well as the national "Moving Medicine" website for doctors, the Exercise Medicine clinic at Leicester General Hospital, and menopause clinics in Leicester and Nottingham.
There is a lack of understanding of how these changes in body composition occur. However, for muscle to decrease in size, there must be an imbalance between how quickly we remove muscle proteins and how quickly we make new muscle proteins. We have recently developed advanced biochemistry techniques to measure how quickly we make and remove muscle proteins. By applying these techniques to pre- and post-menopausal women, we will be able to better understand muscle protein balance during ageing for the first time. By combining these techniques with magnetic resonance imaging (MRI), we will develop new methods to locate where, and how quickly, new fat is deposited in the body. Combined, these approaches will provide vital insights on how best to target future interventions against sarcopenia in women.
Resistance exercise therapy (RET) currently offers the most effective strategy to promote muscle mass and strength in ageing. However, responses to resistance exercise are blunted in older women compared to younger women. We will measure whether the menopause has an impact on how quickly new muscle proteins are made in response to exercise, and, using our MRI imaging techniques, we will monitor whether RET alters the rate of fat deposition in the body. Together, these measures will determine the effectiveness of RET at slowing sarcopenia and improving body composition in post-menopausal women. Using our results, we will create evidence-based resources and information, and implement these recommendations into menopause intervention programmes through existing connections with Sport England Active Partnerships (Active Together in Leicestershire and Sport Notts), Sports Exercise Medicine departments at the Universities of Nottingham and Leicester and the National Centre for Sport and Exercise Medicine in Loughborough, as well as the national "Moving Medicine" website for doctors, the Exercise Medicine clinic at Leicester General Hospital, and menopause clinics in Leicester and Nottingham.
Technical Summary
Sarcopenia results in physical frailty and functional impairments. With a growing aged population, sarcopenia represents one of the largest problems facing our health care services. Sarcopenia develops earlier in women and coincides with the menopause, resulting in greater levels of physical disability compared with men. Loss of muscle mass coincides with increased adiposity and ectopic fat infiltration into muscle, which is associated with decreased muscle performance, insulin resistance and greater metabolic dysfunction. The mechanistic sex differences with ageing are unclear. Strategies to combat sarcopenia are lacking, with resistance exercise therapy currently offering the most effective tool. Yet, we do not know how the menopause affects responses to exercise, and there is a lack of evidence-based guidance on how much and what type of exercise should be performed.
The main aim of this project is bring together interdisciplinary techniques to understand how the menopause accelerates sarcopenia, influences changes in body composition and affects responses to exercise, using groups of age-matched pre- and post-menopausal women. We will use advanced non-invasive oral tracer techniques to measure 'free-living' muscle protein synthesis, breakdown and whole-body muscle mass, and map the distribution of newly created fat using deuterium magnetic resonance, providing a holistic view of muscle protein balance in age-matched pre- and post-menopausal women. We will also assess the acceptability and effectiveness of resistance exercise therapy to determine whether standard approaches remain effective after the menopause.
Successful delivery will provide new knowledge of how the menopause affects muscle protein turnover, rates of adiposity and responses to resistance exercise therapy in post-menopausal women. We will integrate participant interview responses with our physiological findings such that potential RET regimes are optimal and feasible.
The main aim of this project is bring together interdisciplinary techniques to understand how the menopause accelerates sarcopenia, influences changes in body composition and affects responses to exercise, using groups of age-matched pre- and post-menopausal women. We will use advanced non-invasive oral tracer techniques to measure 'free-living' muscle protein synthesis, breakdown and whole-body muscle mass, and map the distribution of newly created fat using deuterium magnetic resonance, providing a holistic view of muscle protein balance in age-matched pre- and post-menopausal women. We will also assess the acceptability and effectiveness of resistance exercise therapy to determine whether standard approaches remain effective after the menopause.
Successful delivery will provide new knowledge of how the menopause affects muscle protein turnover, rates of adiposity and responses to resistance exercise therapy in post-menopausal women. We will integrate participant interview responses with our physiological findings such that potential RET regimes are optimal and feasible.
