Move, don't worry about catching upHealth Beauty | Stacey Burling 28 Sep 2021
Experts say people who put off exercising until their retirement years are at a disadvantage. They enter late life - a time when strong muscles and good aerobic capacity can make the difference between independence and disability - with poorer-quality blood vessels, nerves and muscles than peers who have always been fit. New exercisers can repair much of the damage, but, probably, not all of it.
"We can't undo 20 years of terrible living," said Dan Ritchie, co-founder and president of the Functional Aging Institute. But the good news is that you don't have to catch up to the lifelong runners and gym rats to improve your health. "You can take really unfit people at 70," he said, "and get them fit and doing amazing things."
Seventy-seven-year-old David Pallett, who began exercising seriously about four months ago, jokes about besting his very strong 30-year-old son at arm wrestling.
Pallett listened when his son encouraged him to exercise. "I told him I could beat him. I know I'll never beat him. I'm too old, and he's too young. He wanted me to get healthy because he didn't want me to die."
As Melissa Markofski, an exercise physiologist and aging expert at the University of Houston, said: "Comparison is the root of unhappiness."
But let's start by doing it anyway.
Physical activity is one of the most important things people can do to increase the number of healthy years in their lifespan, and experts say it's better to start young.
"I'm a huge fan of exercise, because, without question, it's the most effective means that we have today to counter the fundamental biology of aging," said Nathan LeBrasseur, a Mayo Clinic physiologist and physical therapist, who studies muscle growth and metabolism.
Aging, he said, is the "accumulation of molecular and cellular damage." It drives dysfunction and disease. Exercise can slow it down while obesity, which often accompanies low activity, accelerates it.
People reach their physical peak at about 30, said Steven Austad, chair of biology at the University of Alabama-Birmingham and senior scientific director of the American Federation for Aging Research.
We lose about 30 percent of our muscle mass and 50 percent of strength in later life. Exercisers sustain higher levels of mass longer, so they start their decline from a higher point than sedentary peers. Although you can still add muscle in your 80s and 90s, it becomes much harder, researchers said.
"You want to walk into your 80s with as much muscle mass as possible," said Kevin Murach, an exercise physiologist and muscle biologist at the University of Arkansas. His recent research - in mice - suggests that people who exercise in early life but take a long break might build muscle more quickly if they start again than never-exercisers.
Scott Trappe, director of the Human Performance Laboratory at Ball State University, said that longtime exercisers have a bigger physiologic reserve that helps them bounce back from illness or injuries. "Their tank is bigger," he said.
Even scientists love to point to rare elder super-achievers who started exercising late: a 100-year-old bicycle racer who was able to improve his aerobic capacity, or Charles Eugster, who started at 85 and then won rowing and bodybuilding competitions.
But most experts said there's reason to think you probably won't be a masters champion if you do your first exercising in your 60s or 70s - because you're starting so far behind. It's easier to maintain strength and fitness than it is to increase it, said Thomas Buford, director of the University of Alabama-Birmingham's Center for Exercise Medicine. "Most of what we're talking about is preventing decline," he said.
Whether we exercise or not, we lose muscle mass over time. You don't have to have big muscles to be strong, but experts said mass correlates with strength.
The composition of muscle changes, with fewer and shorter fibers. In heavier, more sedentary people, fat deposits can make muscle look like marbled steak. Older people also have fewer mitochondria, which facilitate muscle contractions.
All of these problems are worse in sedentary people. Some can be improved with exercise.
LeBrasseur said people who study muscles have long been consumed with age-related decline in muscle mass, but are starting to look at other factors.
"Have we oversold the importance of building mass as opposed to building muscle quality?" he wondered.
By that, he means that muscles don't operate independently. They need a good blood supply and well-connected nerves that tell them when to contract and relax. These things decline with age, too, and they decline more in people who haven't exercised.
A healthy brain is key to strong muscles because that's where the signals that control muscles start, said Brian Clark, an Ohio University exercise physiologist.
"The muscles are the puppets of the nervous system," he said. Our brains atrophy with age and that affects motor function as well as thinking. This can make habitual motions like walking more challenging. Nerves are also dying, and they become less connected.
The best activity for your brain is aerobic exercise. Weightlifting can also build better connections between nerves and muscles. In fact, much of the improvement that sedentary people experience during the first eight weeks of lifting weights is due to this improved neuromuscular coordination, LeBrasseur said.
Then there's your heart, which supplies muscles with nutrients and oxygen. Exercisers have more muscle capillaries and suppler arteries than the sedentary.
Neel Chokshi, director of Penn Medicine's sports cardiology and fitness program, said VO2 max, which measures how much oxygen your body can use during exercise, is a sign of cardiovascular efficiency.
It declines over time. Arteries stiffen or develop plaque. This makes it harder for the heart to pump. The heart muscle itself can also thicken and lose pumping ability. Some of the stiffening of artery walls cannot be reversed. Chokshi said aerobic exercise is also best for your cardiovascular system.
At any age, exercise as simple as walking can help people avoid catastrophic falls and stave off the day when they'll need a walker or wheelchair. "There's never a time in your life when increasing your physical activity is not beneficial," Austad said.
It also can be pretty gratifying. "The thing about weak flabby muscles," he said, "is if you change them just a little, it can have enormous impact."
The Philadelphia Inquirer (TNS)