We now have truckloads of evidence that exercise affects how long and well we will live.

Studies have shown us that older athletes develop and retain stronger bones, hearts, muscles, and brains than people of the very same age who rarely work out. It turns out that people who begin to exercise in midlife, even if they have not been involved in exercising for years, can rapidly gain most of the longevity benefits of working out. So it is some truth to that rumor that you hear in the gym, about muscles having memory.

The insight comes from researchers with the National Cancer Institute who mined data from the N.I.H.-AARP Diet and Health Study, an observational inquiry that was organized in 1995 and chronicled responses from men and women, aged 50 to 71. After reviewing the questionnaire responses of more than 280,000 participants, our researchers checked the National Death index for deaths and their causes among the subjects in the years since they had joined this health study and compared the risks of dying among the different groups.

However, not surprisingly, the results, which was published in JAMA Network Open in March 2019, revealing that men and women who had been sedentary throughout their lives were the ones most likely now to have died, particularly from heart disease. On the other hand, those people who always had been active throughout their lives, exercising consistently for just a few hours a week, were about 30 to 35 percent less likely to have passed away from any cause and about 40 percent less likely to have died from a heart attack than the consistently inactive people.

More buoying people who had stopped exercising for a decade or more but had begun again during their 40s or 50s, working out for only a few hours a week, shared the very same relative protection against premature death as the individuals who always had exercised. Conversely, people who had been active and stayed in shape as teenagers or young adults but sedentary in middle age seemed to lose any longevity benefits. They were as likely as the always-inactive group to have passed away.

However, this study did rely on individuals recall of their past behavior, which can perhaps, be notoriously unreliable. Because, that the inquiry was observational, it can tell us that exercise in middle age is associated with a longer life, but not whether exercise alone causes us to live longer. Other factors are most likely to be involved, such as our wealth, diets, weight, and our over-all general health and our genes. For anyone that is interested in longevity, the message is a twofold one, says one of the study’s authors, Pedro Saint-Maurice, who is a postdoctoral gentleman at the National Cancer Institute: IF YOU ARE ACTIVE, KEEP BEING ACTIVE, AND IF YOU ARE NOT, IT’S REALLY NOT TOO LATE.

By now most of us know that walking and other physical activity are indispensable to our over-all well-being. Studies show that active people have lower incidences of heart disease, Type 2 diabetes, and obesity and usually live longer than people who are sedentary. But how much walking do we need? And how many steps do we need to take? Many of us probably assume that this answer 10,000, since activity monitors often use that threshold as a goal for us. It is a number that is not supported by any science, but it seems to have originated with a clockmaker who is Japanese in the 1960s. The company gave its consumer pedometer a Japanese name that translates as “10,000 steps,” and somehow my friends, that ideal took hold in a very big way.

Let us take in consideration, while some past research suggests that we might need to take more than 10,000 steps in-order to protect ourselves against heart disease, a recent study of activity and mortality in older women suggests that the magic number could be as low as 4,500 steps per day, and that even small increases in steps can be meaningful for health.

This data also showed that a woman who reached that threshold was about 40% less likely to have died during the follow-up period than someone who was taking about 2,700 steps per day. “We were quite surprised that such a relatively small number of steps would be associated with such a substantial reduction in mortality,” I-Min Lee, who is a professor of medicine at Harvard University, who led the study says.

To reach their conclusions, the researchers collected the step-count and health data from over 16,000 participants, with most of them in their 70, and not one whom reported poor health. The scientists also checked the death records for the subsequent four to five years and than compared step counts and mortality. Those comparisons proved to be telling, however, the women who had moved the least, taking only about 2,700 steps per day, were the most likely to have died during the follow-up period. The women who more often had considerably less risk of premature death, up to a plateau of about 7,500 steps per day. Our sweet spot for reducing the risk of premature death was about 4,500 steps per day. Of course, we must understand that this study looked at older women and mortality. It is impossible for us to know if the findings apply likewise to men or our younger people, or the risks for diseases and other outcomes.

One of the most important benefits of incorporating exercise into our daily routine is how it reduces our risk of developing a number of types of cancer-especially colorectal cancer, which according to a few estimates is the malignancy most influenced by physical activity. But how does working out guard against colon cancer remains largely in the unknown. A small study that was published in February 2019 in the Journal of Physiology suggests we should also look to any changes in our bloodstream after exercise.

The more recent study was initiated by scientists at the University of Queensland in Brisbane, Australia, with other institutions recruiting 20 men who had survived colon cancer. (Women were excluded only because menstruation might have altered the results.) The scientists asked 10 of the male subjects to start working out strenuously three times a week: riding a stationary bicycle, fast and hard for four minutes, than resting for three minutes, and having them repeating that sequence three more time. After training for one month, the subjects rested quietly while researchers drew blood. The remaining 10 men completed the same four-by-four interval session, however, only once.

The researchers drew their blood before, immediately following and an additional two hours after that lone workout. Scientists added a tiny amount of fluid from the men’s blood to petri dishes containing human colon-cancer tumor cells, which is often used to study the growth of cancer. Counting cell at regular intervals for three day, researchers saw a substantial differences. The fluids taken immediately after one single workout and showed far fewer cancer cells than in those drawn two hours alter exercise.

There was no similar decline in the dishes from the men who had trained for 30 day. In effect, something about the blood being immediately drawn after the workout, slowing the growth of cancer cells. Also, the researchers found a large increase in molecules that was involved in inflammation, which can actually slow cell growth, immediately after exercise. A transitory increase in inflammatory markers after exercise can be helping to jam the proliferation of tumor cells, says Tina Skinner, who is a physiologist and was the senior author of this study.

The implications of the results are cheering and cautionary at the very same time. These changes in exercisers, blood were potent, however, “transient,” says Skinner. So activities would have to be repeated to provide any continuing protection, and it still remains unclear how intense or prolonged that exercise ideally would need to be, or if these effects extend equally to fighting other types of cancer.

Multiple experiments have shown that the brains of an adult can be quite plastic, rewiring themselves in many ways, depending on the lifestyles. It’s been demonstrated, for example, by regular exercise over time will increase the volume of the hippocampus, which is a key part of our brain’s memory networks. However, are those changes short-term, or by continued to workout, do they become long-term? A promising 2019 study at the University of Maryland suggests that even a single, moderate workout can immediately change how the brains function and how well we can recognize common names and similar information.

The findings complement the research from 2013 that looked into the long-term effects of exercise on portions of the human brain involved in semantic-memory processing. Semantic memory is in essence, our knowledge of our world and culture of which we all are a part. It represents the context of our lives- a buildup of our concepts and of common names, such as “What is the color red?” or “Who is John Lennon?” The study from the researchers found that after 12-week program with the treadmill walking, the parts of the brain involved in semantic-memory became less active, a desirable outcome. When it is less brain activity, it suggests that our brain had become more efficient.

In the 2019 University of Maryland study, that was published in The Journal of the International Neuropsychological Society, scientists backtracked to parse all the steps that was involved in getting to this state. They recruited 26 healthy individuals aged between 55 and 85 who had absolutely no serious problems with their memory. In two different lab sessions, participants rested quietly or rode one of the exercise bike for 30 minutes. Afterward, the volunteers submitted to an M.R.I. brain scan and watched as names plucked from a phone book and famous names such as John Lennon flashed on the screen.

Unexpectedly, and very interesting, the parts of the brains most involved in semantic memory fizzed with far more activity after people had exercised than when they had rested. The scientists surmised that it was a training response, that is similar to what happens with our muscles. When people first begin to workout, their muscles burn and strain through energy. However, as they become more in good shape, those same muscles respond more efficiently, using less energy for the same workout. In other words our brain’s memory center become more fit. The study is short-term, though, and does not precisely show the intervening steps that is involved in changing the brain with regular exercise.



My friends, the lesson here is, exercise can only help you to potentially, live a longer quality life, with a better brain function. May you be always in good health.

Humbly yours, Paul Earl.