Tuesday
Feb182020

Ageless Strength

The onset of change need not be feared, because we have ways to battle it every step of the way.

The onset of change need not be feared, because we have ways to battle it every step of the way. “Ageless Strength” author Jeff Horowitz lays out the three reasons we tend to get slower as we get older. 

Our bodies work the same way when we’re older as they do when we’re younger. Our organs, for example, still function the same way that they did when we were younger. But within this apparent sameness, our bodies do experience change. Skin loses elasticity, and hair loses pigment and begins to thin. And while these kinds of changes can be damaging to the ego, they do not threaten our health.

The same can’t be said of other, less obvious changes that we experience to our muscle mass and strength, our bone health, and our balance. Changes in these three areas can impact our health–and our sports performance.

1. Muscle Mass and Strength

In our mid- to late 20s, our muscle mass, strength, and functionality generally peak, because up to that point our bodies are programmed to release hormones that cause continual growth of muscle. As we enter our 30s, however, our bodies exit this programmed growth phase and we begin to run the risk of losing muscle mass and strength in a process called sarcopenia. From that point onward, we can lose as much as 3 to 8 percent of our muscle mass—or up to seven pounds of muscle—every decade.

Many people aren’t even aware that this loss is happening. That’s because we need only a small fraction of our actual strength, 30 percent or so, to get through a typical day. Unless you’ve been doing something much more taxing, such as lifting weights, playing a sport at the elite level, or working in a very strenuous job, a 5 percent loss of strength wouldn’t be immediately obvious because you’d still be able to easily climb stairs, wash your car, or move a box of clothes. But once this loss gets to 50 percent, the effects become much more apparent. Suddenly, tasks that once seemed easy, such as getting up from a couch, feel much harder.

Once this degeneration process begins, it only gets worse if left unchecked. The natural tendency at that point might be to avoid doing those things that feel difficult. But responding with a decrease in physical activity will only lead to further loss of muscle and a corresponding decrease in physical energy and stamina, as our aerobic capacity diminishes along with our strength. To this, add a tendency to gain weight and an overall decrease in health.

The effect of strength on overall health might not be immediately obvious. Muscle mass burns calories, so a decline in muscle tissue will cause a decrease in metabolic activity. This means that the body will burn fewer calories, which can affect insulin sensitivity and hormone levels. This in turn can lead to obesity, diabetes, and cardiovascular disease.

By our 60s and 70s, this loss of muscle mass and strength will have led to increased frailty and risk of falling, as well as decreased independence.

While we can’t stop the age clock, we absolutely can change the way in which we age. Since muscle tissue can be regenerated at any age, we can use strength training to slow down the effects of aging and in some cases, even reverse them.

2. Bone Density

The 206 bones that make up our skeletons provide structure, protection, and support for our bodies, and make movement possible. Despite appearing solid, however, our bones are actually a matrix of protein and minerals, comprised of living tissue that is constantly changing in a process known as remodeling. Specialized cells called osteoclasts break down older bone for reabsorption while other cells called osteoblasts bring protein and minerals—mostly calcium and phosphate—into the bone matrix for sculpting and repair.

During the arc of our lives, much of the cartilage that we’re born with hardens into bone, small bones fuse, and all bones enlarge as we grow into adulthood. Nutrition and lifestyle, among other factors, help determine bone volume and density.

As with all living tissue, bone is susceptible to disease, as well as to disorders linked to insufficient density. One common ailment is osteoporosis, which is a reduction in bone mineral density that raises the risk of fracture. Postmenopausal women in particular are at risk for this disease, although it can strike men and premenopausal women as well.

Aging brings other challenges as well. Lubricating fluid in the joints may decrease, and cartilage may lose water content and become more susceptible to stress, especially in the hips and knees. This can lead to joint stiffness, loss of flexibility, and inflammation and arthritis. Vertebrae may compress, compromising posture and further limiting mobility. Over time, these changes can trigger a downward spiral in health.

But, once again, strength training can come to the rescue by reducing, delaying, and sometimes even reversing these outcomes. This is because strength training can add density and mineral content to aging bone. It performs these miracles in a very straightforward way: by stressing the body and relying on the body’s adaptive response. Just as with muscle, bones respond to resistance by getting tougher and stronger.

3. Balance

Our mastery of balance is due to three things: our vestibular system, our proprioceptive system, and our sight.

  • The vestibular system is in the inner ear. It’s a complex structure made up of chambers and tubes filled with fluid. Specialized nerves inside these structures gather information about the position of the body in relation to the pull of gravity.
  • The proprioceptive system uses nerve receptors in the skeletal muscles to gather information about the position of your body in space—everything from where your arms are to the position of your hips and the tilt of your head.
  • Finally, your sight also contributes to your balance. Your depth perception, night vision, and sense of contrast will all be used by your brain, in conjunction with information from your vestibular system, to create a map of his surroundings in relation to your body’s position.

Your brain will process all of this data nearly instantaneously to determine the position of your body, and then it will use its neural network to engage the muscles that you need to maintain his balance. As you move, your brain will use the ongoing real-time data feed to constantly update your muscle contractions in order to maintain your balance.

It’s an amazing system, a true marvel of evolution. The precise way in which your brain uses your muscles to maintain balance is no less impressive.

The muscles that you engage in balance are your core muscles. These are found in your trunk, from mid-thigh to rib cage, on your front, back, and sides. They include hips, abdominals, and backside muscles. Regarding balance, though, the undisputed champion of all these is the transverse abdominis.

The transverse abdominis is the deepest layer of muscle tissue in our midsection. It wraps around our bodies like a girdle. Whenever we move, the transverse abdominis clenches, holding our bodies in place as we move our arms and legs. It provides the anchor for our movement, giving us leverage to move without falling over.

Eventually, though, we all become unsteady. That’s because loss of balance is one of the key challenges that we face as we age. This is caused by degeneration of each of these systems: our visual acuity, our strength and the ability to use our strength effectively to control the position of our bodies in space, and the function of our inner ear.

As we age, these systems start to become compromised. Our sight, the ability to focus and see things clearly, diminishes with age. So do depth perception, night vision, and sensitivity to contrast. Eye problems can also impair, blur, or distort vision. The loss of these visual faculties compromises balance. The number of nerve cells in the vestibular system and blood flow to the inner ear also decrease after about age 55.

The loss of muscle strength is perhaps the most problematic. Most at risk are the fast-twitch muscle fibers, which provide explosive strength on demand, instantly. We rely on these muscles for quick adjustments in balance. When they’re diminished, we’re unable to catch ourselves easily when we stumble. When we were younger, we were able to use the muscle we had to adequately keep our balance, even if we were generally out of shape, but as we get older and lose muscle mass, we no longer have that luxury. Combined with diminished reflexes and coordination, we’re increasingly likely to fall.

The onset of change need not be feared, because we have ways to battle it every step of the way. For this reason, we won’t call these changes threats, which implies potential helplessness. Instead, we’ll call them challenges, because we possess the ability to meet these problems head on and deal with them.

Monday
Jan202020

The 3 Reasons You’re Slower Than You Used to Be

The onset of change need not be feared, because we have ways to battle it every step of the way.

Our bodies work the same way when we’re older as they do when we’re younger. Our organs, for example, still function the same way that they did when we were younger. But within this apparent sameness, our bodies do experience change. Skin loses elasticity, and hair loses pigment and begins to thin. And while these kinds of changes can be damaging to the ego, they do not threaten our health.

The same can’t be said of other, less obvious changes that we experience to our muscle mass and strength, our bone health, and our balance. Changes in these three areas can impact our health–and our sports performance.

1. Muscle Mass and Strength

In our mid- to late 20s, our muscle mass, strength, and functionality generally peak, because up to that point our bodies are programmed to release hormones that cause continual growth of muscle. As we enter our 30s, however, our bodies exit this programmed growth phase and we begin to run the risk of losing muscle mass and strength in a process called sarcopenia. From that point onward, we can lose as much as 3 to 8 percent of our muscle mass—or up to seven pounds of muscle—every decade.

Many people aren’t even aware that this loss is happening. That’s because we need only a small fraction of our actual strength, 30 percent or so, to get through a typical day. Unless you’ve been doing something much more taxing, such as lifting weights, playing a sport at the elite level, or working in a very strenuous job, a 5 percent loss of strength wouldn’t be immediately obvious because you’d still be able to easily climb stairs, wash your car, or move a box of clothes. But once this loss gets to 50 percent, the effects become much more apparent. Suddenly, tasks that once seemed easy, such as getting up from a couch, feel much harder.

Once this degeneration process begins, it only gets worse if left unchecked. The natural tendency at that point might be to avoid doing those things that feel difficult. But responding with a decrease in physical activity will only lead to further loss of muscle and a corresponding decrease in physical energy and stamina, as our aerobic capacity diminishes along with our strength. To this, add a tendency to gain weight and an overall decrease in health.

The effect of strength on overall health might not be immediately obvious. Muscle mass burns calories, so a decline in muscle tissue will cause a decrease in metabolic activity. This means that the body will burn fewer calories, which can affect insulin sensitivity and hormone levels. This in turn can lead to obesity, diabetes, and cardiovascular disease.

By our 60s and 70s, this loss of muscle mass and strength will have led to increased frailty and risk of falling, as well as decreased independence.

While we can’t stop the age clock, we absolutely can change the way in which we age. Since muscle tissue can be regenerated at any age, we can use strength training to slow down the effects of aging and in some cases, even reverse them.

2. Bone Density

The 206 bones that make up our skeletons provide structure, protection, and support for our bodies, and make movement possible. Despite appearing solid, however, our bones are actually a matrix of protein and minerals, comprised of living tissue that is constantly changing in a process known as remodeling. Specialized cells called osteoclasts break down older bone for reabsorption while other cells called osteoblasts bring protein and minerals—mostly calcium and phosphate—into the bone matrix for sculpting and repair.

During the arc of our lives, much of the cartilage that we’re born with hardens into bone, small bones fuse, and all bones enlarge as we grow into adulthood. Nutrition and lifestyle, among other factors, help determine bone volume and density.

As with all living tissue, bone is susceptible to disease, as well as to disorders linked to insufficient density. One common ailment is osteoporosis, which is a reduction in bone mineral density that raises the risk of fracture. Postmenopausal women in particular are at risk for this disease, although it can strike men and premenopausal women as well.

Aging brings other challenges as well. Lubricating fluid in the joints may decrease, and cartilage may lose water content and become more susceptible to stress, especially in the hips and knees. This can lead to joint stiffness, loss of flexibility, and inflammation and arthritis. Vertebrae may compress, compromising posture and further limiting mobility. Over time, these changes can trigger a downward spiral in health.

But, once again, strength training can come to the rescue by reducing, delaying, and sometimes even reversing these outcomes. This is because strength training can add density and mineral content to aging bone. It performs these miracles in a very straightforward way: by stressing the body and relying on the body’s adaptive response. Just as with muscle, bones respond to resistance by getting tougher and stronger.

3. Balance

Our mastery of balance is due to three things: our vestibular system, our proprioceptive system, and our sight.

  • The vestibular system is in the inner ear. It’s a complex structure made up of chambers and tubes filled with fluid. Specialized nerves inside these structures gather information about the position of the body in relation to the pull of gravity.
  • The proprioceptive system uses nerve receptors in the skeletal muscles to gather information about the position of your body in space—everything from where your arms are to the position of your hips and the tilt of your head.
  • Finally, your sight also contributes to your balance. Your depth perception, night vision, and sense of contrast will all be used by your brain, in conjunction with information from your vestibular system, to create a map of his surroundings in relation to your body’s position.

Your brain will process all of this data nearly instantaneously to determine the position of your body, and then it will use its neural network to engage the muscles that you need to maintain his balance. As you move, your brain will use the ongoing real-time data feed to constantly update your muscle contractions in order to maintain your balance.

It’s an amazing system, a true marvel of evolution. The precise way in which your brain uses your muscles to maintain balance is no less impressive.

The muscles that you engage in balance are your core muscles. These are found in your trunk, from mid-thigh to rib cage, on your front, back, and sides. They include hips, abdominals, and backside muscles. Regarding balance, though, the undisputed champion of all these is the transverse abdominis.

The transverse abdominis is the deepest layer of muscle tissue in our midsection. It wraps around our bodies like a girdle. Whenever we move, the transverse abdominis clenches, holding our bodies in place as we move our arms and legs. It provides the anchor for our movement, giving us leverage to move without falling over.

Eventually, though, we all become unsteady. That’s because loss of balance is one of the key challenges that we face as we age. This is caused by degeneration of each of these systems: our visual acuity, our strength and the ability to use our strength effectively to control the position of our bodies in space, and the function of our inner ear.

As we age, these systems start to become compromised. Our sight, the ability to focus and see things clearly, diminishes with age. So do depth perception, night vision, and sensitivity to contrast. Eye problems can also impair, blur, or distort vision. The loss of these visual faculties compromises balance. The number of nerve cells in the vestibular system and blood flow to the inner ear also decrease after about age 55.

The loss of muscle strength is perhaps the most problematic. Most at risk are the fast-twitch muscle fibers, which provide explosive strength on demand, instantly. We rely on these muscles for quick adjustments in balance. When they’re diminished, we’re unable to catch ourselves easily when we stumble. When we were younger, we were able to use the muscle we had to adequately keep our balance, even if we were generally out of shape, but as we get older and lose muscle mass, we no longer have that luxury. Combined with diminished reflexes and coordination, we’re increasingly likely to fall.

The onset of change need not be feared, because we have ways to battle it every step of the way. For this reason, we won’t call these changes threats, which implies potential helplessness. Instead, we’ll call them challenges, because we possess the ability to meet these problems head on and deal with them.

Tuesday
Oct152019

How Exercise Can Make Your Brain Work Better

Training for endurance might just come with a pretty fantastic bonus.

By Jordan Smith

 

nattrassGetty Images

  • A recent study published in Nature looked at fitness levels in young people and compared that to their brain function.
  • Researchers found that the higher their endurance, the better their brain worked.
  • Fitter individuals scored higher on the cognitive tests and also had higher levels of white matter in the brain—which is your brain’s connection system, responsible for transmission of nerve signals.

You know exercising is smart. But might your workout actually be making you smarter?

In a study published in Nature, a group of over 1,100 people with an average age of about 28 participated in physical and mental tests. In the physical tests, participants walked as fast as they could for two minutes; their distance was measured as a proxy of their endurance. Those who went farthest in the two-minute test scored highest for endurance.

In the mental tests, researchers gauged things like memory, reasoning, and judgement. They also used MRI tests to look at brain function.

The tests revealed the fittest people—those with higher levels of endurance—scored better on the cognitive tests and higher levels of something called fractional anisotropy, which resembles white matter in the brain. White matter is your brain’s communication system—think wires that connect brain parts with each other to share messages, as Jonathan Repple Ph.D., of the department of psychiatry and psychotherapy at the University of Muenster Hospital in Muenster, Germany, explained to Runner’s World. If you have high levels of intact white matter, it means your wiring is solid—your brain is well-connected and brain cells can quickly communicate.

Those with higher endurance also had higher global cognition scores, which measure things like sorting, memory, and recognition to give a view on overall cognitive performance.

 “Better fitness causes better blood supply to the brain, causes an increase in nerve-stimulating hormones, and causes decreases in inflammation, which could lead to better ‘insulation’ of the white matter ‘wires,’” Repple said.

And while more research is needed to prove cause and effect—say, that it’s not that better brain health that leads to better endurance—it seems that your workout can boost both body and mind.

From: Runner's World US

 

 

Monday
Oct142019

Is MX Physically Demanding?

Are motocross riders the fittest athletes in the world?

Competitors in many sports like to think that their sport is the hardest to do, the most physically demanding. There are many lists of the fittest sports, with boxing and gymnastics commonly on top. See our discussion about the Fittest Sports for details. Motocross riders are rarely considered, but should be.

Ever since motocross failed to be listed on the ESPN List of The Most Demanding Sports, there has been great discussion on this site about the physical demands of motocross riding. There is no doubt that it is a tough sport. As well as a lot of anecdotal evidence of how demanding the sport is, many have pointed out that there have been a couple of scientific studies that have supported their assertions.

Motocross Demands

Motocross is a very physically and mentally challenging off-road motorcycle sport, which is raced on natural terrain with man-made obstacles. While undoubtedly the bike does a lot of the work for the rider, to manoeuvre and stay on the 200+ lb machine requires a high level of strength, power and endurance. The riders need to be light and strong, with good strength of the upper body, shoulder and arms, hand grip and legs. A study by Gay et al. found that during a motocross race heart rate is quickly raised, and the competitors average heart rate was between 92-96% of their maximum, indicating that there are very high demands on the aerobic endurance system. See more about fitness for motorsports.

 

 

Motocross bike on a dirt track

The Fittest Sport?

Motocross is definitely physically tough, though is it the most demanding of all sports? It is not an easy thing to measure and compare the fitness of athletes from different sports. You can compare fitness test scores of athletes, but there are issues of varying protocols and athlete levels, and there is not a lot of data on motocross riders for comparison. It is best to compare head to head battles. There are two oft reported studies which have directly compared motocross riders to other athletes, one in 1979 by the National National Athletic Institute and another in 2002 by the University of Pittsburgh Medical Center's (UMPC) Sports Performance Complex.

1979 study by the National Athletic Health Institute (NAHI)

A study was conducted in 1979 at the National Athletic Health Institute in Inglewood, California, founded by pioneer sports orthopedists Drs. Robert Kerlan and Frank Jobe. The original article apparently appeared in a Cycle magazine in early 1980, though this article or any research paper has not been sighted. The information below has been gained from various online reports.

The study compared athletes from a range of sports, including motocross (MX) racers. Other sports tested were American football, gymnastics, wrestling, basketball, soccer, baseball, wrestling, ice skating, track and field, marathon runners and maybe others. The motocross racers included Brad Lackey, Mike Bell, Danny Laporte, Jeff Ward, Kent Howerton plus several others. There was a large range of fitness tests conducted, including a treadmill VO2maxtest, body fat levels using underwater weighing, bench press for upper body strength and leg press for lower body strength.

One report stated the highest scoring sports were found to be long-distance running, gymnastics, wrestling and motocross racing, while another said soccer was top over motocross.

2002 by the University of Pittsburgh Medical Center

A study was conducted in 2002 at the University of Pittsburgh Medical Center's (UMPC) Sports Performance Complex, headed by Alan DeGennaro, the director of UPMC's Sports Performance Program and Brian Hagen, director for rehabilitation medicine at the sports complex. The testing began when the nation's best motocross racers traveled to Pittsburgh for the Steel City Nationals (Round 12 of the U.S. Motocross championships) in Delmont Labor Day weekend in 2002. A battery of tests was performed on about a dozen riders, including Broc Glover and Hannah.

The evaluations included some standard medical checks such as EKGs, blood samples, blood pressure, and more sport specific treadmill maximal oxygen consumption test, body fat levels using underwater weighing and skinfold measures, blood lactate acid buildup, upper body strength via a series of shoulder presses, bench presses and curls, lower body strength strength of quadriceps and hamstring muscles, grip strength, sit-ups, flexibility, and vertical jump power. These results were then compared to published results for other sports. No details of the conclusions of this testing have been found.

Conclusions

Without the specific details of the results of these studies, no conclusions about the claim of motocross riders being the fittest can be made. The lack of published physiological data of riders highlights the need for further study. The data so far indicates that the sport of motocross should be considered in all the discussions about the fittest sports, though there are several other sports worthy of the claim to be the world's fittest sport!

References

  • "UPMC starts study of ways to cut down off-road motocross injuries", By Pohla Smith. Published Tuesday, July 23, 2002, Pittsburgh Post-Gazette,
  • "Are motocross riders athletes? Bikers and researchers say yes", Pocono Record, Aug 30, 2002.
  • "Motocrossers As Athletes", p106, Cycle World Magazine Jan-Feb 1981.
  • Transcript of interview of Brad Lackey by Bobby Myers about his participation in the 1979 NAHI study.
  • "The Exercise Intensity of MX and SX Racing", By Gay, D; Keen, J; Riel, R; Evans, M; Milek ,M; Furman, T; Casillas, E; Augustine, S (senior author) University of Florida HSC - Jacksonville and Jacksonville Orthopedic Institute. link

Other Studies

  • "Physiological characteristics of top level off-road motorcyclists". Gobbi AW, Francisco RA, Tuy B and Kvitne RS. BJSM. 2005; 39:927-931. - comparing off-road motocross, enduro, and desert rally motorcyclists. Motocross riders had more muscle mass, more strength, and greater aerobic power. link
  • "Cardio-respiratory and neuromuscular responses to motocross race", Department of Biology of Physical Activity. University of Jyväskylä. by Tomi Konttinen. 2005. link
  • "Cardiopulmonary loading in motocross riding Tomi Konttinen", Keijo Häkkinen, and Heikki Kyröläinen, Journal Of Sports Sciences Vol. 25 , Iss. 9,2007
  • Saltin, B. 1975. Motocross-ajajan maksimaalinen hapenottokyky ja syketaajuus ajosuorituksen aikana (Motocross rider's maximal oxygen uptake and heart rate during the riding performance). Teoksessa: Husqvarna 250-360 CR. Owner's manual. American edition. Värnamo. Sweden. 1976
  • "Anthropometric Characteristics and Performance Capabilities of Highly Trained Motocross Athletes Compared With Physically Active Men", Bach, Christopher W.; Brown, Ann F.; Kinsey, Amber W.; Ormsbee, Michael J. Journal of Strength and Conditioning Research December 2015 Vol. 29 - Issue 12: p 3392–3398. - results suggest highly trained MX athletes possess certain physiological adaptations that likely result from sport-specific demands compared with physically trained men.

Unverified

Here are a few more mentions of other studies that I have found online, but were unable to find any more evidence. Let me know if you have details to add or can verify the details below.

  • "extensive tests were done by the Swedish Physiological Institution way back in the mid-1960's. The researchers names were Bengt Saltin and Goran Agnevik."
  • "In the late 60's early 70's some Swedish Sports scientist (maybe from Husqvana) did a study which found MX to be the most physically demanding sport in the world ... Professional Tennis came in second. "
  • "In the 90's German scientists compared many top German sports people and Pit Beirer came out as fittest of them all."
Monday
Oct072019

Endurance Exercise May Be a Speed Bump That Slows Down Alzheimer’s

 

It’s never too late to start healthy habits that can reduce your risk.

By Elizabeth Millard

Oct 4, 2019

 

Heide BenserGetty Images

  • Endurance exercise can reduce the progression of atrophy in a part of the brain associated with memory among people at risk of Alzheimer’s disease, a new study found.
  • Exercise can improve blood vessel health and boost the production of compounds that support developing brain neurons, experts believe.

Currently, there is no cure for Alzheimer’s disease, and previous research has discovered that the rate of progression and changes in brain atrophy—or the loss of nerve cells called neurons in your brain—often varies by individual, making the condition even tougher to predict and treat.

But a new study published in the Journal of Alzheimer’s Disease joins a growing tide of research about one possible speed bump for dementia and Alzheimer’s: regular exercise.

Researchers at UT Southwestern Medical Center compared cognitive function and brain volume in 70 sedentary, older adults with memory issues and mild cognitive impairment. They separated them into two groups, one doing aerobic exercise and the other concentrating on stretching.

The dose of aerobic training was based on each individual’s fitness level, assessed with VO2 testing, But no matter what their starting point, every participant in that group progressively increased the frequency and intensity of their exercise sessions over time, starting with three times per week for about a half hour at 75 to 85 percent of max heart rate.

By week 26, they were doing four to five sessions per week for about 40 minutes per time, at 85 to 90 percent of max heart rate for the workout.

The stretching group participants stayed at below 50 percent of max heart rate and focused on full-body stretches, with resistance bands introduced about halfway through the program.

At the end of a year, both groups showed evidence of slightly improved neuropsychological scores, and scored about the same on cognitive tests. Memory and executive function—which includes things like reasoning and problem-solving skills—also improved for all participants.

But when the researchers looked at how the buildup changed of amyloid—a type of plaque that’s considered a hallmark of Alzheimer’s and dementia because it destroys neurons in the brain—they saw some important differences:

Those in the exercise group who had amyloid buildup at the start of the study experienced slightly less volume reduction in their hippocampus—the part of the brain involved in memory—compared to those in the stretching group.

This is a big deal because previous research has shown that people who have more amyloid beta also tend to experience more shrinkage in that part of the brain.

So if exercise can keep the amyloid in check, then that could mean dementia could progress at a slower rate. The reason why aerobic exercise has this effect isn’t clear yet, according to lead author Ron Zhang, Ph.D., professor of neurology and neurotherapeutics at UT Southwestern. But, he told Bicycling, it may have to do with how exercise enhances brain neurotrophic factors—molecules that support developing neurons—and blood vessel function, which could both reduce the harmful effects of amyloid on your brain cells.

He added that further studies need to be done, especially in large, randomized, controlled trials, to determine how much exercise is needed for the best effect, especially since people can respond to exercise differently.

“But, for now, it would be safe to say that engaging in moderate to vigorous physical activity not only benefits your heart, but also your brain,” said Zhang.

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