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Well DUH ! Of course children need to run, run, run or somehow exercise to get rid of excess energy. That's why recess is so important (but unfortunately so many schools are eliminating it). It is incredibly hard for children to quietly sit for many, many hours straight like little robots working tirelessly on schoolwork, especially those with high energy levels to start with. From Medscape:

Before-School Exercise May Reduce ADHD Symptoms

Moderate to vigorous aerobic exercise in the morning may reduce symptoms of attention-deficit/hyperactivity disorder (ADHD) in young children at risk for the illness, new research suggests.

A randomized study of 202 kindergarteners, 1st graders, and 2nd graders showed that those who completed 12 weeks of before-school physical activity had significantly higher reductions in inattention and moodiness than those who completed a sedentary classroom-based intervention.In addition, the subgroup of children with elevated ADHD symptoms who went through the before-school exercise program showed reduced impairment associated with ADHD risk in both their school and home settings.

"We need more studies to replicate the results, but I think the take-home message is that aerobic exercise is a health-producing activity ― and there are really no negative side effects from it," added Dr. Hoza.

Past research has shown some positive effects from exercise on patients with ADHD, providing evidence that it may be "a viable strategy for improving symptoms, behavior, achievement, inhibitory control, and neurocognitive function in youth with elevated ADHD symptoms," write the investigators.

In the current study, the researchers enrolled 94 children at risk for ADHD and 108 children deemed "typically developing" to act as their control group....The physical activity involved continuous movement requiring children to breathe hard and included a variety of age-appropriate activities and games.

"Although our findings indicated that all participants showed improvements, children with ADHD risk receiving exercise benefited across a broader range of outcomes than those receiving the sedentary activities," said coinvestigator Alan Smith, PhD, chair of the Department of Kinesiology at Michigan State University in East Lansing, in a release.

Excerpts from an article by Jane Brody in the NY Times:

Beating Back the Risk of Diabetes

This year, nearly two million American adults and more than 5,000 children and adolescents will learn they have a potentially devastating, life-shortening, yet largely preventable disease: Type 2 diabetes. They will join 29.1 million Americans who already have diabetes.

Diabetes and its complications are responsible for nearly 200,000 deaths a year; the fatality rate among affected adults is 50 percent higher than among similar people without diabetes. Alarmingly, recent studies even have linked diabetes to an increased risk of dementia and Alzheimer's disease. Even people with above-average blood glucose levels, but not diabetes, have an elevated risk.

The Diabetes Prevention Program study, conducted among about 3,800 people who had pre-diabetes, found that moderate weight loss — an average of 12 pounds —  reduced the odds of progression to diabetes by nearly 50 percent.

An excellent discussion of what is known about the effect on diabetes of various foods and supplements appeared recently in Nutrition Action Healthletter at cspinet.org/iceberg.pdf. Some highlights:

Carbohydrates - breads, grains, cereals, sugary drinks and sweets of all kinds — are most problematic for people with diabetes or at risk of developing it. Carbohydrates are eventually metabolized to glucose, which raises the body’s demand for insulin. Consume less of them in general, and choose whole-grain versions whenever possible.

If you must have sweet drinks, select artificially sweetened ones. In two huge studies of nurses and other health professionals who were followed for 22 years, those who drank one or more sugary soft drinks a day had about a 30 percent higher risk of developing diabetes than those who rarely drank them, even after their weight was taken into account.

But there’s good news about coffee. Two or three cups of coffee (but not tea) a day, with or without caffeine, have been consistently linked to a lower risk of Type 2 diabetes. 

For protein, limit consumption of red meat, especially processed meats like sausages, hot dogs and luncheon meats, which are linked to a higher diabetes risk. Instead, choose fish, lean poultry (skinless and not fried), beans and nuts. Low-fat dairy products, including yogurt, and even fatty ones may lower the risk of diabetes; the reason is unclear.

Most protective are green, leafy vegetables — spinach, chard, kale, collards, mustard greens and even lettuce — as well as cruciferous vegetables like cabbage, broccoli and cauliflower. But all vegetables are good and should fill at least two-thirds of your dinner plate.

The nutrients magnesium and vitamin D are also potentially protective. In fact, the preventive value of leafy greens, whole grains, beans and nuts may lie in their high magnesium content. In a well-designed clinical trial of 32 overweight people with insulin resistance, the prelude to diabetes, blood glucose levels and insulin sensitivity improved in those who took a daily magnesium supplement for six months. Don’t go overboard: More than 350 milligrams of magnesium daily can cause diarrhea. 

Vitamin D, long known to be crucial to healthy bones, may also be helpful. In one study of 92 overweight or obese adults with prediabetes, those who took a supplement of 2,000 international units of vitamin D daily had better function of the pancreatic cells that produce insulin..

Of course, how much you weigh and what you eat are not the only concerns. Regular, preferably daily, physical exercise is a vital component of any prevention and treatment program for Type 2 diabetes, or most any chronic ailment. Weight loss can reduce diabetes risk by about 50 percent, but adding exercise to that can lower the odds by 70 percent, compared with people who remain overweight and inactive, according to a study that followed nearly 85,000 female nurses for 16 years. Women who were active for seven or more hours weekly had half the risk of developing diabetes as did women who exercised only a half-hour a week.

Good news! From Science Daily:

Taking short walking breaks found to reverse negative effects of prolonged sitting

Three easy -- one could even say slow -- 5-minute walks can reverse harm caused to leg arteries during three hours of prolonged sitting, researchers report. Sitting for long periods of time is associated with risk factors such as higher cholesterol levels and greater waist circumference that can lead to cardiovascular and metabolic disease. When people sit, slack muscles do not contract to effectively pump blood to the heart. Blood can pool in the legs and affect the endothelial function of arteries, or the ability of blood vessels to expand from increased blood flow.

The researchers were able to demonstrate that during a three-hour period, the flow-mediated dilation, or the expansion of the arteries as a result of increased blood flow, of the main artery in the legs was impaired by as much as 50 percent after just one hour. The study participants who walked for 5 minutes each hour of sitting saw their arterial function stay the same -- it did not drop throughout the three-hour period. Thosar says it is likely that the increase in muscle activity and blood flow accounts for this.

Several more articles on the benefits of exercise. From Science Daily:

Train your heart to protect your mind

Exercising to improve our cardiovascular strength may protect us from cognitive impairment as we age, according to a new study. "Our body's arteries stiffen with age, and the vessel hardening is believed to begin in the aorta, the main vessel coming out of the heart, before reaching the brain. Indeed, the hardening may contribute to cognitive changes that occur during a similar time frame," explained the first author of the study. "We found that older adults whose aortas were in a better condition and who had greater aerobic fitness performed better on a cognitive test. We therefore think that the preservation of vessel elasticity may be one of the mechanisms that enables exercise to slow cognitive aging."

The researchers worked with 31 young people between the ages of 18 and 30 and 54 older participants aged between 55 and 75. This enabled the team to compare the older participants within their peer group and against the younger group who obviously have not begun the aging processes in question. None of the participants had physical or mental health issues that might influence the study outcome.

The results demonstrated age-related declines in executive function, aortic elasticity and cardiorespiratory fitness, a link between vascular health and brain function, and a positive association between aerobic fitness and brain function. "Although the impact of fitness on cerebral vasculature may however involve other, more complex mechanisms, overall these results support the hypothesis that lifestyle helps maintain the elasticity of arteries, thereby preventing downstream cerebrovascular damage and resulting in preserved cognitive abilities in later life."

From Science Daily:

Physically fit kids have beefier brain white matter than their less-fit peers

A new study of 9- and 10-year-olds finds that those who are more aerobically fit have more fibrous and compact white-matter tracts in the brain than their peers who are less fit. 'White matter' describes the bundles of axons that carry nerve signals from one brain region to another. More compact white matter is associated with faster and more efficient nerve activity.

The analysis revealed significant fitness-related differences in the integrity of several white-matter tracts in the brain: the corpus callosum, which connects the brain's left and right hemispheres; the superior longitudinal fasciculus, a pair of structures that connect the frontal and parietal lobes; and the superior corona radiata, which connect the cerebral cortex to the brain stem."All of these tracts have been found to play a role in attention and memory," Chaddock-Heyman said. 

From Science Daily:

Exercise may protect older women from irregular heartbeat

Increasing the amount or intensity of physical activity can cut the chances of older women developing a life-threatening irregular heartbeat, according to new research. Researchers found that post-menopausal women who were the most physically active had a 10 percent lower risk of developing atrial fibrillation (AF), compared to women with low levels of physical activity, even if they were obese. Obesity is an important risk factor for atrial fibrillation.

Excellent way to lower breast cancer risk. From Science Daily:

Postmenopausal breast cancer risk decreases rapidly after starting regular physical activity

Postmenopausal women who in the past four years had undertaken regular physical activity equivalent to at least four hours of walking per week had a lower risk for invasive breast cancer compared with women who exercised less during those four years, according to new data.

"Twelve MET-h [metabolic equivalent task-hours] per week corresponds to walking four hours per week or cycling or engaging in other sports two hours per week and it is consistent with the World Cancer Research Fund recommendations of walking at least 30 minutes daily," said Agnès Fournier, PhD, a researcher in the Centre for Research in Epidemiology and Population Health at the Institut Gustave Roussy in Villejuif, France. "So, our study shows that it is not necessary to engage in vigorous or very frequent activities; even walking 30 minutes per day is beneficial."

Postmenopausal women who in the previous four years had undertaken 12 or more MET-h of physical activity each week had a 10 percent decreased risk of invasive breast cancer compared with women who were less active. Women who undertook this level of physical activity between five and nine years earlier but were less active in the four years prior to the final data collection did not have a decreased risk for invasive breast cancer

"We found that recreational physical activity, even of modest intensity, seemed to have a rapid impact on breast cancer risk. However, the decreased breast cancer risk we found associated with physical activity was attenuated when activity stopped. As a result, postmenopausal women who exercise should be encouraged to continue and those who do not exercise should consider starting because their risk of breast cancer may decrease rapidly."

Fournier and colleagues analyzed data obtained from biennial questionnaires completed by 59,308 postmenopausal women who were enrolled in E3N, the French component of the European Prospective Investigation Into Cancer and Nutrition (EPIC) study. The mean duration of follow-up was 8.5 years, during which time, 2,155 of the women were diagnosed with a first primary invasive breast cancer.

Sounds like exercising in moderation has health benefits for all people, while "to excess" can be problematic. From Science Daily:

Contrary to popular belief, more exercise is not always better

There is strong epidemiological evidence of the importance of regular physical activity, such as brisk walking and jogging, in the management and rehabilitation of cardiovascular disease and in lowering the risk of death from other diseases such as hypertension, stroke, and type 2 diabetes. The Physical Activity Guidelines for Americans recommends about 150 minutes per week of moderate-intensity exercise or about 75 minutes of vigorous-intensity exercise. But there is clear evidence of an increase in cardiovascular deaths in heart attack survivors who exercise to excess.

Paul T. Williams, PhD, of the Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, and Paul D. Thompson, MD, of the Department of Cardiology, Hartford Hospital, Hartford, CT, studied the relationship between exercise and cardiovascular disease-related deaths in about 2,400 physically active heart attack survivors. This study confirmed previous reports indicating that the cardiovascular benefits for walking and running were equivalent, as long as the energy expenditures were the same (although when walking, as compared to running, it will take about twice as long to burn the same number of calories).

Remarkable dose-dependent reductions in deaths from cardiovascular events of up to 65% were seen among patients who were running less than 30 miles or walking less than 46 miles per week. Beyond this point however much of the benefit of exercise was lost, in what is described as a reverse J-curve pattern.

In the same issue, investigators in Spain report on a meta-analysis of ten cohort studies aimed at providing an accurate overview of mortality in elite athletes. The studies included over 42,000 top athletes (707 women) who had participated in a range of sports including football, baseball, track and field, and cycling, including Olympic level athletes and participants in the Tour de France.

"What we found on the evidence available was that elite athletes (mostly men) live longer than the general population, which suggests that the beneficial health effects of exercise, particularly in decreasing cardiovascular disease and cancer risk, are not necessarily confined to moderate doses," comments senior investigator Alejandro Lucia, MD, PhD, of the European University Madrid, Spain. 

"Extrapolation of the data from the current Williams and Thompson study to the general population would suggest that approximately one out of twenty people is overdoing exercise," comments James H. O'Keefe, MD, from the Mid America Heart Institute in Kansas City, MO... Along with co-authors Carl "Chip" Lavie, MD, and Barry Franklin, PhD, he explains that "we have suggested the term 'cardiac overuse injury' for this increasingly common consequence of the 'more exercise is better' strategy." 

O'Keefe, Franklin and Lavie point out that a weekly cumulative dose of vigorous exercise of not more than about five hours has been identified in several studies to be the safe upper range for long-term cardiovascular health and life expectancy, and that it may also be beneficial to take one or two days a week off from vigorous exercise, and to refrain from high-intensity exercise on an everyday basis. They propose that individuals from either end of the exercise spectrum (sedentary people and over-exercisers) would probably reap long-term health benefits by changing their physical activity levels to be in the moderate range.

"For patients with heart disease, almost all should be exercising, and generally most should be exercising 30-40 minutes most days, but from a health stand-point, there is no reason to exercise much longer than that and especially not more than 60 minutes on most days," says Lavie, who is a cardiologist at the John Ochsner Heart and Vascular Institute, New Orleans, LA. 

This is Part 3 on how lifestyle influences aging. Many recent research reports tell of a link between our lifestyle and how we'll age - whether we'll be active and healthy well into our 80s or in terrible shape and dying young. Mind you, these are not "definites" because nothing can give you a guarantee, but they are ways we can improve our odds in living a long and healthy life. From Medical Xpress:

Having a sense of purpose may add years to your life, study finds

Feeling that you have a sense of purpose in life may help you live longer, no matter what your age, according to new research. The research has clear implications for promoting positive aging and adult development, says the lead researcher.

The researchers looked at data from over 6000 participants, focusing on their self-reported purpose in life (e.g., "Some people wander aimlessly through life, but I am not one of them") and other psychosocial variables that gauged their positive relations with others and their experience of positive and negative emotions.

Greater purpose in life consistently predicted lower  across the lifespan, showing the same benefit for younger, middle-aged, and older participants across the follow-up period. "To show that purpose predicts longer lives for younger and older adults alike is pretty interesting, and underscores the power of the construct," he explains.

From Science Daily:

Education boosts brain function long after school, study shows

Education significantly improves mental functioning in seniors even four decades after finishing school, shows a new study. The study shows that people who attended school for longer periods performed better in terms of cognitive functioning than those who did not. Using data from individuals aged around 60, the researchers found a positive impact of schooling on memory scores. The fact that young people or their parents did not choose whether to go longer to school strongly suggests that schooling is the cause rather than personal characteristics that would affect this choice and could also explain the differences in cognitive function.

From Medscape:

Lifetime of Intellectual Enrichment Keeps Aging Brain Sharp

A lifetime of intellectual enrichment helps delay onset of cognitive decline in older individuals, new data from the Mayo Clinic Study on Aging show.

In this longitudinal study, researchers found ties between higher levels of education and working in mentally stimulating jobs in early- to mid-life, as well as higher levels of mid- to late-life cognitive activity, such as using a computer, reading, and participating in social activities, and better cognition with age..."We also found that an individual with low education/occupation benefited more by engaging in high mid-/late-life cognitive activity than an individual with high education/occupation," Dr. Vemuri noted.

A number of research results were reported at the Alzheimer's Association International Conference 2014.  From Science Daily:

Potential Alzheimer's disease risk factor and risk reduction strategies become clearer

Participation in activities that promote mental activity, and moderate physical activity in middle age, may help protect against the development of Alzheimer's disease and dementia in later life, according to new research.

From Science Daily:

Physical activity is beneficial for late-life cognition

Physical activity in midlife seems to protect from dementia in old age, according to a study. Those who engaged in physical activity at least twice a week had a lower risk of dementia than those who were less active. The protective effects were particularly strong among overweight individuals. In addition, the results showed that becoming more physically active after midlife may also contribute to lowering dementia risk.

This is Part 2 on how lifestyle influences aging. Many recent research reports tell of a link between our lifestyle and how we'll age - whether we'll be active and healthy well into our 80s or in terrible shape and dying young. Mind you, these are not "definites" because nothing can give you a guarantee, but they are ways we can improve our odds in living the long and healthy life that we want. From February 2014 Medscape:

Cancers Caused by Lifestyle Behaviors: Experts Urge Action

In launching the World Cancer Report 2014 earlier this week, the editors emphasized the need for prevention and highlighted lifestyle behaviors that lead to cancer, including smoking tobacco, drinking alcohol, overweight/obesity, and lack of exerciseThe report, issued by the International Agency for Research on Cancer (IACR), contains contributions from more than 250 scientists worldwide, many of them leading experts in their fields. 

In the United States, 1 in 3 cancer deaths is related to obesity, poor nutrition, or physical inactivity, and the problem will only increase as more countries and regions adopt the diet and lifestyles of more economically developed economies."

Tobacco, both smoked and smokeless, remains the world's leading cause of cancer morbidity and mortality, the report notes. The IACR and also the US Surgeon General have concluded that the relationship with smoking is causal for cancers of the nasal and oral cavities, hypopharynx, larynx, trachea, esophagus, lung, bronchus, bone marrow (leukemia), stomach, kidney, pancreas, ureter, uterus, bladder, and cervix. The IACR expands this list to also include paranasal sinuses, liver, colon, rectum, and ovary (mucinous), but says it is unclear if there is a link with breast cancer.

Still under-recognized, and not acted on, is the association between drinking alcohol and cancer. The agency says cancers caused by drinking alcoholic beverages include those of the oral cavity, pharynx, larynx, esophagus, liver, colorectum, and female breast.

Excess body fat increases the risk for cancers of the esophagus, colon, pancreas, endometrium, and kidney, as well as postmenopausal breast cancer. The evidence for obesity increasing the risk for these cancers is "convincing," the agency comments, and there is a dose–response relationship, so being overweight is less risky than being obese.

Regular physical activity reduces the risk for multiple cancers by contributing to weight control, and also reduces the risk for colorectal and breast cancer by additional mechanisms. The general consensus among researchers is that exercise should be of moderate intensity and average at least an hour each day.

High consumption of red meat, especially processed meat, is associated with a risk for colorectal cancer. "A diet high in fruit and vegetables and whole grains does not appear to be as strongly protective against cancer as initially believed," the report notes. "However, this dietary pattern is still advisable because of the benefits for diabetes and cardiovascular diseases, and some possible reductions in cancer incidence."

From Science Daily:

Watching too much TV may increase risk of early death: Three hours a day linked to premature death from any cause

Adults who watch TV three hours or more a day may double their risk of premature death from any cause. Researchers suggest adults should consider getting regular exercise, avoiding long sedentary periods and reducing TV viewing to one to two hours a day.

Results of a large study published in the Mayo Clinic Proceedings. From Science Daily:

Large waist linked to poor health, even among those in healthy body mass index ranges

Having a big belly has consequences beyond trouble squeezing into your pants. It’s detrimental to your health, even if you have a healthy body mass index (BMI), a new international collaborative study has found. Men and women with large waist circumferences were more likely to die younger, and were more likely to die from illnesses such as heart disease, respiratory problems, and cancer after accounting for body mass index, smoking, alcohol use and physical activity.

Some good news for those who have to sit for long periods every day at work - being physically fit may help. From Science Daily:

Physical fitness associated with less pronounced effect of sedentary behavior

Physical fitness may buffer some of the adverse health effects of too much sitting, according to a new study. Sedentary behavior has been linked to an increase risk of obesity, metabolic syndrome, type 2 diabetes mellitus, cardiovascular disease, some cancers, and premature death. But previous studies of the association have not taken into account the protective impact of fitness, a strong predictor of cardiovascular disease incidence and mortality.

I've been seeing research report after report looking at how our lifestyle determines how we'll age - whether we'll be active and healthy well into our 80s or in terrible shape and dying young. Mind you, these are not "definites" because nothing can give you a guarantee, but they are ways we can improve our odds in living the long and healthy life that we want. From Medical Xpress:

A healthy lifestyle adds years to life

Live longer thanks to fruit, an active lifestyle, limited alcohol and no cigarettes. This is the conclusion of a study by public health physicians at the University of Zurich who documented for the first time the impact of behavioural factors on life expectancy in numbers. 

...Brian Martin and his colleagues from the Institute of Social and Preventive Medicine (ISPM) at the University of Zurich have examined the effects of these four factors – both individual and combined – on life expectancy. An individual who smokes, drinks a lot, is physically inactive and has an unhealthy diet has 2.5 fold higher mortality risk in epidemiological terms than an individual who looks after his health. Or to put it positively: "A healthy lifestyle can help you stay ten years' younger", comments the lead author Eva Martin-Diener.

"The effect of each individual factor on life expectancy is relatively high", states Eva Martin-Diener. But smoking seems to be the most harmful. Compared with a group of non-smokers, smokers have a 57 percent higher risk of dying prematurely. The impact of an unhealthy diet, not enough sport and alcohol abuse results in an elevated mortality risk of around 15 percent for each factor.

According to Martin an unhealthy lifestyle has above all a long-lasting impact. Whereas high wine consumption, cigarettes, an unhealthy diet and physical inactivity scarcely had any effect on mortality amongst the 45 to 55-year-olds, it does have a visible effect on 65 to 75-year-olds. The probability of a 75-year-old man with none of the four risk factors surviving the next ten years is 67 percent, exactly the same as the risk for a smoker who is ten years younger, doesn't exercise, eats unhealthily and drinks a lot.

From Medical Xpress:

Picking up healthy habits in your 30s and 40s can slash heart disease risk

The heart is more forgiving than you may think—especially to adults who try to take charge of their health, a new Northwestern Medicine study has found. When adults in their 30s and 40s decide to drop unhealthy habits that are harmful to their heart and embrace healthy lifestyle changes, they can control and potentially even reverse the natural progression of , scientists found. On the flip side, scientists also found that if people drop  or pick up more bad habits as they age, there is measurable, detrimental impact on their coronary arteries.

For this paper, scientists examined healthy lifestyle behaviors and coronary artery calcification and thickening among the more than 5,000 participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study who were assessed at baseline (when participants were ages 18 to 30) and 20 years later.The healthy  assessed were: not being overweight/obese, being a nonsmoker and physically active and having low alcohol intake and a healthy diet. 

By young adulthood (at the beginning of the study), less than 10 percent of the CARDIA participants reported all five healthy lifestyle behaviors. At the 20-year mark, about 25 percent of the study participants had added at least one healthy lifestyle behavior. Each increase in healthy lifestyle factors was associated with reduced odds of detectable  and lower intima-media thickness—two major markers of cardiovascular disease that can predict future cardiovascular events. Adulthood is not too late for healthy behavior changes to help the heart."

"That loss of healthy habits had a measurable negative impact on their coronary arteries," Spring said. "Each decrease in healthy lifestyle factors led to greater odds of detectable  calcification and higher intima-media thickness.

Spring said the healthy changes people in the study made are attainable and sustainable. She offers some tips for those who want to embrace a  at any age:Keep a healthy body weight; Don't smoke; Engage in at least 30 minutes of moderate to vigorous activity five times a week; No more than one alcoholic drink a day for women, no more than two for men; Eat a healthy diet, high in fiber, low in sodium with lots of fruit and vegetables.

From Science Daily:

Adults who lose weight at any age could enjoy improved cardiovascular health

Weight loss at any age in adulthood is worthwhile because it could yield long-term heart and vascular benefits, suggests new research. For the first time, the findings indicate that adults who drop a BMI category -- from obese to overweight, or from overweight to normal -- at any time during adult life, even if they regain weight, can reduce these cardiovascular manifestations. The findings are from a study examining the impact of lifelong patterns of weight change on cardiovascular risk factors in a group of British men and women followed since birth in March 1946. 

Research reports and articles on the benefits of exercise have been piling up. Here are some worth looking at. From Science Daily:

Sitting too much, not just lack of exercise, is detrimental to cardiovascular health

Cardiologists have found that sedentary behaviors may lower cardiorespiratory fitness levels. New evidence suggests that two hours of sedentary behavior can be just as harmful as 20 minutes of exercise is beneficial.

From Science Daily:

Out of shape? Your memory may suffer

Here's another reason to drop that doughnut and hit the treadmill: A new study suggests aerobic fitness affects long-term memory. "The findings show that lower-fit individuals lose more memory across time," said a co-author. The study is one of the first to investigate young, supposedly healthy adults. 

From Science Daily:

Less exercise, not more calories, responsible for expanding waistlines

Sedentary lifestyle and not caloric intake may be to blame for increased obesity in the US, according to a new analysis. A study reveals that in the past 20 years there has been a sharp decrease in physical exercise and an increase in average body mass index (BMI), while caloric intake has remained steady. 

From Science Daily:

Older adults: Build muscle and you'll live longer

The more muscle mass older Americans have, the less likely they are to die prematurely, new research shows. The findings add to the growing evidence that overall body composition -- and not the widely used body mass index, or BMI -- is a better predictor of all-cause mortality. "In other words, the greater your muscle mass, the lower your risk of death," said the study's co-author. "Thus, rather than worrying about weight or body mass index, we should be trying to maximize and maintain muscle mass."

From Medical Xpress:

Keeping active pays off in your 70s and 80s

Older people who undertake at least 25 minutes of moderate or vigorous exercise everyday need fewer prescriptions and are less likely to be admitted to hospital in an emergency, new research has revealed.

Researchers from the Universities of Bath, Bristol and UWE-Bristol looked at data from 213 people whose average age was 78. Of people studied, those who carried out more than 25 minutes of moderate to vigorous physical activity per day – such as walking quickly, cycling or swimming - received 50 per cent fewer prescriptions than those who were more active over a four to five year period.

Such physical activity leads to a higher metabolism and better circulation, reducing the risk of conditions and diseases common in older age such as high blood presure, type 2 diabetes, coronary heart disease, and strokes.

From Everyday Health:

The Best Anti-Aging Medicine? Exercise

Everyone knows that exercise is good for you — it helps manage weight, improves muscle and bone strength, and even lifts your spirits. It can also add years to your life.“People have been looking for the secret to a long and healthy life for millennia,” said Neil Resnick, MD, chief of the division of geriatrics and director of the University of Pittsburgh Institute on Aging. “It turns out the most powerful intervention is exercise.”

A recent study conducted at Harvard found that exercise can be at least as effective as prescription drugs when it comes to preventing common conditions such as heart disease, stroke, and diabetes.

Exercise at any age is beneficial. From Science Daily:

Seniors who exercise regularly experience less physical decline as they age

Older adults in retirement communities who reported more exercise experienced less physical decline than their peers who reported less exercise, although many adults -- even those who exercised -- did not complete muscle-strengthening exercises, which are another defense against physical decline.