Muscle matters: Dr Brendan Egan at TEDxUCD

as you sit there in your chair you expend in a rough amount of energy somewhere around a calorie per minute when we exercise we can increase this by about 20 or 30 fold as you sit there your muscle country's about 30 percent of your energy during exercise a contributor of 90 percent of your energy so it becomes the major site where we burn carbohydrate and fat and when we eat a meal about 80 percent of the energy that's ingested in that meal is distributed to the muscle in other words when muscle begins to fail or when we develop problems with a muscle is it's not surprising then that we develop a range of diseases associated with that there's two things that have happened in modern science that have unintended consequences in terms of the way that muscle functions the first is automation so in modern life now we're predisposed to being physically inactive we spend a large amount of our time in a sitting position so even if we do or half-hour of purposeful exercise first thing in the morning we spend it about 90 percent of the next 15 and a half hours of waking we spend our time in a seated position so one of the problems with sitting is that it's an independent risk factor for a majority of diseases in other words even if you do exercise first thing in the morning or last thing at night or whenever you exercise you're in the day if you do in a single bout and you spend the rest of your day sitting you might be called what's classified as an act active couch potato so potatoes are much used for muscles and so if you look at someone like this and we tend to associate inactivity and inappropriate diet with that with the increase in size in actual fact the muscles of individuals such as this guy on the couch are actually getting smaller and smaller and working less and less the second major thing that modern science has delivered us is medication and as a result we're living longer and longer so we have a worldwide aging or grain population and if you look at the yellow segment on those pie charts that represents the numbers of people who are over 65 so a current projections sometime after the year 2050 the numbers of people who are greater than 65 years of age will exceed the numbers of people who are less than 15 years of age for the first time in human history however with the aging and with extended lifespans due to this improvements in our medication unfortunately that's associated with chronic diseases so in data from the US adults aged over 65 years the current numbers would suggest that ninety two point two percent of those individuals have one or more chronic diseases so although we're living longer we might not necessarily be living healthier in this case chronic diseases were defined as the usual ones we tend to hear about hypertension coronary heart disease stroke cancer and so forth but as one disease that's not mentioned here that I want to talk a bit more about today in that sarcopenia so sarcopenia is defined as the edge related wasting of muscle and the in the word comes from greek which means a poverty of flesh but it also means a poverty of strength so we lose muscle mass and we lose strength as we age and there's no way it's inescapable it's a fact that happens after about the age of 30 we lose it 3 to 8% of our muscle every decade keep that number in mind because I'm going to come back to it so every decade we lose somewhere between 3 and 8 percent of our muscle on the right hand side and in the second figure there you see the appearance of the time muscle of an individual cross section of their tie and what you can see there is at an elderly individual they've lost a large proportion of the muscle mass so the white color there indicates adipose tissue or fat so muscle is shrunk we've lost muscle as we age beneath that is a 74 year old athlete who has trained their whole life and it's managed maintained their muscle mass and despite what I said was the inescapable fact we would lose muscle throughout our life so you might wonder what is the prevalence of sarcopenia is it just some disease that this guy is really interested you know it's not really that relevant well at the moment in over 65s it's about twenty verse this is data from the US it's about twenty percent prevalence in people over the age of 85 greater than half of the individuals have sarcopenia now when you lose strength and you lose power in your muscles you lose these are these are things that are greatly associated with balance if you lose your capacity to balance you're more predisposed to Falls and fractures so this loss of muscle mass is a is a strong risk factor for frailty syndromes for loss of Independence and for general ill health as we age we don't have any figures for Ireland but what we do know in Ireland is that this there's another pair to this story which is disease related malnutrition and this might surprise you but in Ireland at any one time there's 140,000 people who are suffering from disease related malnutrition that cost about indirect costs about 1.5 billion euro to the Exchequer and you might think well how much does that mean you know is what kind of disease is this again that's more than the direct cost of obesity so this is a this is a an invisible type of disease disease related malnutrition very strongly associated with age-related muscle wasting so why is strength important I mentioned the incidence of frailty and loss of Independence if we look at individuals who are either over 60 or under 60 and we look at their strength so their whole body strikes three colors here represent weak individuals the average individuals to strong individuals if you look at the two red bars what you see there is that as we age so the over-60s day over four and four times elevated death rate compared to the under 60s so that makes sense if we're a little older we're more likely to die however on the right-hand side if you compare the green to the red the stronger that you are so the strongest heart of the population have half the death rate of those who are weakest in other words if you preserve your muscle mass you have a greater chance of living that little bit longer now why would that effect be so obvious and why would it be of relevance to something like cancer so are there are other diseases that that sarcopenia or muscle-wasting relate to and there are so all of these diseases listed on this slide and cone coincide with muscle wasting so in each one of those when the disease manifests itself it's also associated with the loss of muscle mass and therefore a loss of Independence what I want to focus on is a mobilization and bed rest so if you take young healthy males in the twenties student aged student population and you've probably heard of this ten thousand steps that you need to do in any given day in order to be to be healthy if you take people who were making those ten thousand steps and you reduce their activity by making them take elevators and make them take escalators pushing around in wheelchairs making them sit a lot more we reduce their number of steps to two thousand they lose about five percent of the muscle mass in the space of 14 days so I said that usually we lose about three to eight percent per decade over the age of thirty these guys lose 5% of their muscle mass within 14 days if an elderly person over the age of 70 is bedridden for ten days they lose 10% to the most of us in other words depending on the situation in as little as two weeks you can lose the equivalent muscle mass of what would take a decade to lose so we want to avoid these things we want to avoid mobilization we want to stay active we want to avoid bed rest where possible so how should we do this and typically what we're told is that we need to get out and walk more we need to do half an hour of activity accumulated on five different days of the week well I'm going to tell you that that's probably not enough so the principle of specificity in terms of exercise training is that the body adapts specifically to the the imposed demands so if we want to get bigger if we want to improve our strength and improve our muscles we have to lift weight going out for a walk isn't going to make you stronger and in fact there's some evidence to say that like people who are lifelong in aerobic or querida sports to losing muscle mass compared to those individuals who do strength training the other interesting thing is that when it comes to diseases like diabetes and obesity the most recent evidence would suggest that it's combined endurance and robic exercise that works you shouldn't just be doing one or the other there should be a combination within there a second principle in an exercise training is the principle of progressive overload and this is Milo the wrestler two and a half thousand years ago famous Greek wrestler and the story goes that in order to develop his strength as he as he grew he used to carry a bull a calf around from a young age so he carried it every day and as the bull got bigger he got stronger I don't know if this is true but the point is that each day he pushed himself a little bit harder and his body adapted accordingly and that's what an important principle of the way we exercise so then the question is if an adult is old around this case they're over there over 85 years of age if we exercise train them can they actually make improvements so on the left hand side what you're seeing there it's pre-imposed too much you're looking at the cross-section area and in this particular individual that person's muscle in the quad again they're in their time muscle has increased by about 44% on the right hand side you're looking at their improvement in strength it's improved by about 50% that was after 12 weeks of training that focused on anti-partisan muscles in 85 year old individuals so in this case the muscle wasting could be reversed in other words we've reversed the aging process so how should we exercise then does it have to have to go to a gym do we have to do to have to invest in expensive equipment something we're excited about aucd at the moment is using bodyweight exercises so these are exercises that you use your own bodyweight in space to provide a resistance against your against your against your muscles so I'll give you two little studies that we've done right now we took young college age males again obese and overweight and we trained them for six weeks three days a week half an hour each day and all they did were these body which type exercises no equipment after six weeks we saw about a three percent improvement in muscle mass particularly in the legs and we have that holy grail that lasts a small bit of fat as well there were young individuals in older adults starting at the age of 55 would have a mean age of about 63 we see the same thing after 12 weeks body weight on the exercises three times a week we see about a three percent improvement in in their muscle mass so improving muscle mass is one thing but these exercises are very similar to things that we do and not in everyday activities so we lift things above our head we get up off the ground we get up out of chairs so these are what we call activities of daily living and one of the major predictors of loss of Independence is when an older adult can no longer do these activities of daily living so we're excited now to begin to look at these bodyweight exercises and how they might improve the overall health and function functional capacity of older adults so I suppose the last thing I'll say is that in the case of sarcopenia or muscle wasting you don't just wake up one day and have this situation it's a continuum progresses over time and so I was talking about those bodyweight exercises being able to increase muscle mass but if we can just delay the aging process so if we if we just maintain muscle mass rather than actually having to improve it in that in itself would have benefits to their overall health so my simple message is this we need to prescribe exercise like we prescribed medicine so we shouldn't just give everyone to say a medicine we should treat the individual and we should treat the condition so going out and doing 30 minutes of walking every day might not call it when it comes to people who have age related muscle wasting so in other words what I'd say is usage or lose it because muscle matters and only the strong survive thank you you you

Channel: TEDx Talks

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Keywords: Muscle Matters, Nutrition, Sarcopenia, ted talks, Football, TEDx, UCD, GAA, tedx talks, Sport, tedx talk, Sligo, ted, Sports Science, ted talk, Ageing, Health, Ireland, tedx, Exercise, University College Dublin (College/University), ted x, Muscle

Id: LkXwfTsqQgQ

Length: 13min 58sec (838 seconds)

Published: Fri Jun 27 2014