Interrupting prolonged sitting with periodic “activity snacks” may help maintain muscle mass and quality, according to a new study by researchers at the University of Toronto.
Daniel Moore, an associate professor of muscle physiology at the Faculty of Kinesiology & Physical Eduction (KPE) who led the study, found that short bouts of activity, such as two minutes of walking or body weight sit-to-stand squats, allow the body to use more amino acids from meals to build muscle proteins.
The research was recently published in the Journal of Applied Physiology.
“We know that prolonged sedentary periods impair the body’s ability to filter sugar from the blood following a meal,” says Moore, who heads the Iovate/Muscletech Metabolism & Sports Science Lab at KPE.
“However, breaking up this sedentary period with brief bouts of activity such as two minutes of moderate intensity walking or rising and lowering 15 times from a chair (i.e. body weight squats), can improve the way our body clears sugar from our meals.”
Measuring handgrip strength is one of the main ways of detecting sarcopenia, a syndrome characterized by loss of muscle mass, force and function.
Sarcopenia, a clinical syndrome characterized by progressive and extensive decline in skeletal muscle mass, force and function, is widely considered part of aging. Early diagnosis is extremely important and begins with handgrip measurement using a dynamometer.
A recent study by researchers at the Federal University of São Carlos (UFSCar) in São Paulo state, Brazil, collaborating with colleagues at University College London (UCL) in the United Kingdom, concluded that the diagnosis protocol should be changed by raising the handgrip strength cutoff point used to detect muscle weakness. They say new criteria proposed in their paper would be better predictors of mortality risk in older adults, enabling healthcare professionals to detect the onset of sarcopenia earlier and more accurately.
A new large scale genetic analysis has found biological mechanisms that contribute to making people more susceptible to muscle weakness in later life, finding that diseases such as osteoarthritis and diabetes may play a large role in susceptibility.
As we get older we lose muscle strength, and in some people this severe weakness impacts their ability to live everyday lives, a condition called sarcopenia. Around 10 per cent of people over 50 experience sarcopenia. Many causes thought to impact likelihood of developing this weakness, which is linked to higher death rates.
In a genetic analysis of over 250,000 people aged over 60 from UK Biobank and 21 other cohorts, an international team led by researchers at the University of Exeter looked at hand grip strength, using thresholds of loss of muscle function derived from international definitions of sarcopenia.
The team, including collaborators from the USA and the Netherlands, then conducted a genetic analysis, and found specific biological mechanisms push some people towards sarcopenia, while protecting others. The study, published in Nature Communications identified 15 areas of the genome, or loci, associated with muscle weakness, including 12 loci not implicated in previous analyses of continuous measures of grip strength.
Biomarkers in the blood including red blood cells and inflammation may also share causal pathways with sarcopenia. Together, these results highlight specific areas for intervention or for identifying those at most risk.
Lead author Garan Jones said: “The strongest associations we found were close to regions of the genome regulating the immune system, and growth and development of the muscloskeletal system. However, we also discovered associations with regions not previously known to be linked to muscloskeletal traits.
“We found that our analysis of muscle weakness in older people shared common genetic pathways with metabolic diseases such as type-2 diabetes, and auto-immune conditions such as osteoarthritis and rheumatoid arthritis. In subgroups of people with increased risk of these conditions, sarcopenia may be a key outcome to look out for and prevent.
“We hope that by understanding the genetic contributions to muscle weakness with age, we will be able to highlight possible therapeutic interventions earlier in life, which would lead to a happier and healthier old age.”
The saying goes there are two certainties in life: death and taxes. But men should also add loss of muscle mass to the list.
Age-related muscle loss, called sarcopenia, is a natural part of aging. After age 30, you begin to lose as much as 3% to 5% per decade. Most men will lose about 30% of their muscle mass during their lifetimes.
Less muscle means greater weakness and less mobility, both of which may increase your risk of falls and fractures. A 2015 report from the American Society for Bone and Mineral Research found that people with sarcopenia had 2.3 times the risk of having a low-trauma fracture from a fall, such as a broken hip, collarbone, leg, arm, or wrist.
But just because you lose muscle mass does not mean it is gone forever. “Older men can indeed increase muscle mass lost as a consequence of aging,” says Dr. Thomas W. Storer, director of the exercise physiology and physical function lab at Harvard-affiliated Brigham and Women’s Hospital. “It takes work, dedication, and a plan, but it is never too late to rebuild muscle and maintain it.”
The hormone factor
One possible contributor to sarcopenia is the natural decline of testosterone, the hormone that stimulates protein synthesis and muscle growth. Think of testosterone as the fuel for your muscle-building fire. Continue reading →
I think the best thing about counting calories is that it demystifies weight management. It is a very useful tool in managing your weight. There is no longer a conundrum about how much to eat, or did I eat too much? When you get into calories, it becomes simple arithmetic. If you can add and subtract, you can lose weight by counting calories. Of course, you need to exercise discipline, too. So, weight-management becomes a character-building process.
In the old days you had to write everything down. These days, you can use your computer, or cell phone to get calorie counts and track your intake.
There are 3500 calories in apound.
A 165 lb man has a daily budget of 2200 calories a day to maintain his weight.
To lose weight, e.g. a pound a week, (This is a healthy rate. Much more than this is not healthy or recommended. Remember, it took you months/years to put those pounds on, don’t expect them to evaporate overnight.) you need to take in 500 calories per day less than the 2200 you need to maintain your weight, or 1700 calories.
There is more than one way to do skin a cat, or to get to be a skinny cat. You can eat 500 less calories, or you can burn off 500 more calories, or any combination thereof. A compromise would to be eat 250 calories less and do 250 calories worth of exercise, maybe 40 minutes on the treadmill. That kind of practice pays aerobic dividends and allows you to eat more.
Another avenue to weight loss is to increase your lean muscle mass through a weight training regimen. Muscles burn calories, fat does not.
In the beginning of weight training you may slow your rate of weight loss. Don’t fret, you are reducing your waistline at the same time and reshaping your body in ways that you will like. You will find your clothes fitting better even while your weight remains steady. That is a very nice feeling. Muscle is also slimmer than fat and so are you.
When you increase your lean muscle mass, you are making yourself into a fat burning machine. How good is that?
Tony
Wellness Secrets of a SuperAger 