There’s an old joke that if you give up smoking it’s not that you live longer it just seems that way - or drinking, the same applies. Now, it seems, the real way to keep yourself living longer is to keep your body shape lean. OK, it’s a statistic not a guarantee, but if you do keep yourself lean then statistically you give yourself the best chance of living longer according to some recently published research. On top of that, another piece of research asserts that if you lift weights - twice a week, say - that’s another way to extend your life-expectancy. And with particular relevance to SGSC, when it comes to the weight-lifting research it’s based on results from the observation of weight-lifting among older adults.
The two reports are as follows.
Research Fellow Dr Mingyang Song of Harvard University and colleagues wanted to study how the way that people’s body shape changed over time, especially when leading to obesity, influenced the likelihood of early death. They had as their subjects 80,000 women and 36,000 men and divided them into groupings according to the subjects’ starting body-shape plus any self-reported change in their Body Mass Index over the course of their lives from age 5-50. They then classified them accordingly. One group were classified as “lean-stable” - people who started with a lean body shape and whose weight stayed stable over the period - and they were used as the reference group. Another group was “lean/marked increase” - started lean and gained a marked amount of weight - and so on with the final group classified as “heavy-stable/marked increase” - started heavy and gained more weight. Having taken self-reported results from the age of five to fifty for all the subjects, all the groups were then followed from age 60 over the course of 15-16 years, and the rate of death from all causes was compared with their grouping / classification.
The results were clear, those who ended up with a lean weight in later life had the lowest all-cause death-rate and those who were the obese to start with, at age 50 and up to the end of the study period had the highest rate of early all-cause death. There is some evidence to support a decrease in all-cause mortality - although not cause-specific mortality - among overweight, as opposed to obese, people but the researchers believe that this was “ far from conclusive owing to methodological limitations”. So from this research the longest lived were among those people who had a lean body shape from an early age, and kept it into later adult life.
The second piece of research dealt with strength training. Led by Dr. Jennifer Kraschnewski, assistant professor of medicine and public health sciences at Penn State College of Medicine, the researchers starting point was several previous research studies which had found “that older adults who are physically active have better quality of life and a lower risk of mortality.” Over the past decade or more, research has widened from observing the benefits of just “keeping active”, as it is described, to looking in addition at the “quality of life” benefits for older adults of strength training - something we have previously reported on at SGSC. Now researchers have found that, in addition to these “quality of life” benefits, strength training twice a week also reduces early mortality rates hugely!
Using data from the 1997-2001 National Health Interview Survey, covering 30,000 individuals aged 65 and older, and comparing it to “death certificate data” up to 2011, the results showed that people who did strength training twice a week had up to “46 percent lower odds of death for any reason than those who did not. They also had 41 percent lower odds of cardiac death and 19 percent lower odds of dying from cancer.” So the conclusion of the research is that older adults who undertook strength training twice a week lived longer.
And here’s an interesting thing looking at this from the point of view of a Silver Grey athlete - when you put the two things together they connect with each other.
In Professor Pontzer’s research on the limitations of using exercise as a way of losing weight, he referred to the necessity of discounting from his research results the variable amount of fat-free mass that individuals had. This is because people with a higher amount of fat-free mass, i.e. muscle, have a higher base metabolic rate than those with less muscle due to muscle being an active body part. Muscle uses up calories by virtue of having electric impulses going through it all the time, whereas body fat is an inert part of the body and uses no calories just by existing. He also referred, in an email exchange with us, to the fact that the process of building muscle uses up calories.
So, what can we deduce from these two pieces of research? If you want to live longer, stay lean. And if you want to stay lean then make sure you have a functionally adequate amount of muscle, as having more muscle means you will use up more of the calories in the food you eat so less will be built up as body fat. And, as an older adult, in order to maintain or create that muscle you have to undertake weight training - and now it seems that lifting weights itself gives you a greater likelihood of living longer!
So for Silver Greys, “Muscles x= Leanness = Longevity squared” - as a mathematician or a coder might put it!