By Elizabeth Kimani-Murage, Associate Research Scientist, APHRC
The goal of public health is that “people die young as late as possible,” someone reminded me. But wait a minute, what does that mean? This should mean living for as long as possible while still being strong, energetic and healthy i.e. with the highest quality of life. To put it in a positive tone, “the goal of public health is that people stay young for as long as possible in spite of their age”
Aging, quality of life and longevity
Did you know that you could improve your quality of life and longevity by preventing skeletal muscle loss and weakening as you age? Did you also know that you could do this by staying physically active, eating and drinking right and sleeping adequately?
From birth to around halfway in the third decade of life, one’s muscles grow larger and stronger. From the second half of the third decade, one begins to lose muscle mass and function, a condition known as age-related sarcopenia, associated with loss of muscle (in Greek it means “poverty of flesh”), strength and mobility hence frailty and impairment in the ability to do activities of daily living. Sarcopenia is associated with aging, sedentary lifestyle and a sub-optimal diet. The rate of sarcopenia increases with age and sedentariness. By age 50 years, one can lose up to 0.4 pounds (or 0.2kg) of muscle mass per year. Physical inactivity can lead to a loss in muscle mass of up to 5% per decade after the third decade of life. Physically active people still lose their muscle mass, but at a much lower rate.
The basal metabolic rate (the rate at which the human body expends energy when at rest) decreases substantially after the third decade of life, hence a lower basal metabolic rate as one ages. A lower basal metabolic rate combined with an unhealthy diet, physical inactivity and age-related sarcopenia could lead to excess body fat which may have a negative impact on quality of life. Evidence indicates that preservation of muscle mass and prevention of sarcopenia can lead to prevention of the decrease in metabolic rate. Skeletal muscle loss may also contribute to age-related changes including reduction in insulin sensitivity (which may lead to diabetes and other related metabolic diseases), bone density (which may lead to osteoporosis, hence higher risk of bone fractures), aerobic capacity i.e. “the maximal amount of physiologic work that an individual can do as measured by oxygen consumption” and poor balance and falls resulting in fractures.
The importance of sleep in muscle relaxation and building cannot be overemphasized! During sleep, growth hormones are released and protein synthesis occurs (in the relaxed state particularly during deep sleep) to rebuild broken down muscles. Lack of adequate sleep has been found to decrease the rate at which the body builds and repairs muscles.
Exercise is for everybody; “lean” people too! Physical inactivity is the fourth leading risk factor for global mortality as it is implicated in many non-communicable diseases. It is estimated to be the chief cause for approximately 21–25% of breast and colon cancer burden, 27% of diabetes and approximately 30% of ischaemic heart disease burden. For adults aged 18-64 years (of course if you are reading this article you are most likely in this group), the World Health Organization recommends:
At least 150 minutes of moderate-intensity aerobic physical activity throughout the week, or do at least 75 minutes of vigorous-intensity aerobic physical activity throughout the week, or an equivalent combination of moderate- and vigorous-intensity activity. (ii) Aerobic activity should be performed in bouts of at least 10 minutes duration. (iii) For additional health benefits, adults should increase their moderate-intensity aerobic physical activity to 300 minutes per week, or engage in 150 minutes of vigorous-intensity aerobic physical activity per week, or an equivalent combination of moderate- and vigorous-intensity activity. (iv) Muscle-strengthening activities should be done involving major muscle groups on 2 or more days a week.
Eat a balanced diet to ensure that muscles get the amino acids, vitamins, and minerals they need to repair, build and stay strong. A healthy diet should include adequate fruits and vegetables, complex carbohydrates, milk and dairy products, and limited high fat or high sugar foods. Use the “eatwell plate” to guide your choice of a balanced diet: See picture below for details or go to http://www.nhs.uk/Livewell/Goodfood/Pages/eatwell-plate.aspx.
The eat well plate is based on the food groups that are critical for your health: (i) Fruits and vegetables (eat at least five portions) per day for vitamins, minerals and fibre; (ii) Complex Carbohydrates (should form a third of your meals per day for energy); (iii) Milk and dairy foods (Eat about 2-3 portions a day for protein, calcium, minerals and vitamins). See more on the importance of milk and milk products at http://aphrc.org/blogs/its-got-to-be-milk/; (iv) Meat, fish, eggs, beans and other sources of protein (Eat about 2-3 portions a day for protein, calcium and minerals).
The fifth group on the eatwell plate is “Foods and drinks high in fat and/or sugar” that should be only eaten occasionally and in small portions. Studies in rats have indicated that reducing the amount of calories in one’s diet may result in improved protein synthesis (hence muscle building) and muscle activity. Studies have also found that undernourishment can lead to sacorpenia.
Additionally, take lots of water. Water is important for re-hydration of your body cells, flushing toxins out of vital organs, and carrying nutrients to your body cells. It also increases metabolism. About two liters of water is recommended per day, but men may need more.
Muscles are repaired and made in bed! Your body needs at least eight hours of sleep for optimal recovery… don’t just go to the gym! At least eight hours of sleep will ensure you go through all the stages of sleep, hence you reach the deep sleep stage when most of muscle building occurs.
Laugh and smile more to boost your immunity, reduce stress and pain. Try to remain mentally active because you treat your brain muscles that need to be kept fit.
You may think that you are still young, and sarcopenia does not apply to you, but evidence indicates that the earlier we start, the better. And even if you are an older person it’s never too late to start, though getting a check-up by a doctor is advised before you start any rigorous physical exercise regimen.
Overall, we could all restrict our level of muscle mass loss and weakening and hence avoid the brunt of the effects of sarcopenia. The time to start, if you are not already on track, is today, now!
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