The uptick of worldwide obesity may not seem to be as great a global concern as terrorism or climate change. Particularly when you consider the gaining of 3.3 pounds over 10-year period recently reported in an article published in The Lancet, a prestigious British medical journal, pales in comparison to the 20-pounds-in-20-years weight gain recorded by the typical American following high school.

But it is as serious as it is subtle.Especially when you realize what the increase really means. Researchers took all the weight gained in the adult world during the last four decades and then divided it by all the world's adults, including those in third-world countries that suffered through years of famine.From this bit of math, the researchers uncovered that the increase in weight worldwide has been 3.3 pounds per person per decade from 1975 until 2015. As a result, according to body mass index more adults in the world are obese than underweight for the very first time.In the last 40 years, the number of obese people worldwide has gone from 105 million to 641 million. If this pattern continues, about 20 percent of the world's adult population will be obese by the year 2025, including 44 percent of all American adults.Because this weight increase has been created by a cascade of changed behaviors, it's complicated to counteract on a grand scale. But if you don't want to weigh a grand on the scale (well, more like a quarter of it), there's a simple thing to do.Move. More than you presently do. Preferably in the form of sustained exercise, but any movement helps. Yet better than the benefit of controlling your body weight, increased movement improves your quality of life. Especially as you age.In a study published this winter in the journal Medicine & Science in Sports & Medicine, researchers found that those 50 and over who move more and sit less live longer than those the same age who move less and sit more. To determine this, 3,000 subjects between the ages of 50 and 79 wore accelerometers - activity trackers - for seven days years ago.In the next 10 years, those who were found to be least active in terms of total amount of movement during those seven days were five times more likely to die than those deemed most active. Even those who fell into the middle range in amount of movement were three times less likely to die than the least active.The primary author of the article, Ezra Fishman, who is working toward a doctorate in demography at the University of Pennsylvania, summed it up this way in an article for Medical News Today: "When it comes to physical activity, more is better than less, and anything is better than nothing."Proof of Fishman's belief is found in a similar study published in the Journal of the American Heart Association in 2015. Again, researchers put activity trackers on older adults, this time 1,000 in their 70s and 80s who were in some way physically limited.For the results to show that those who did the most physical movement were the least likely to have heart problems over the next 10 years was no big surprise. The fact that even minimal movement lowered the risk, such as typical chores around the house like putting away dishes, was.A third study shows that those who engage in strenuous movement as they age benefit even more.Researchers at the University of Guelph in Canada studied world-class track and field athletes in their 80s against others that age who had aged successfully and remained fully independent.Through muscle biopsies, the researchers found that the athletes had nearly one-third more muscle fibers and nerves in their legs, which produces bigger muscles and provides more strength. Enough strength, in fact, to score 25 percent higher on tests.While the researchers will not rule out to some degree the effect of genetics as to why the world-class athletes retained more muscle and strength, they are confident that much of the retention resulted from the far tougher-than-typical exercise.While you may be nowhere near 80, if you're over 25 and not engaged in regular bouts of strength training, you're still probably losing muscle mass. In fact, if you don't exercise in your 20s and 30s, you tend to lose 3 to 5 percent of your muscle mass each decade.By your 40s, losing some muscle mass almost always occurs since the loss of some muscle fibers and nerves by that time is inevitable. By your mid-50s, the loss usually accelerates significantly - though it can be greatly slowed by doing strength training regularly and intensely.If you don't have the time, the temperament, or the desire for strength training, you still can help your overall health by thinking about your typical week and finding ways to incorporate more movement. Any movement.Let Fishman's words provide the fire: "When it comes to physical activity, more is better than less, and anything is better than nothing."Contact Kevin Kolodziejski at

kolo@ptd.net