Skip to content

I feel like I'm posting the same thing over and over as study after study finds the same or similar results. Bottom line: sitting much is bad for health, so get up and move (walks are good). The more you move or exercise, the better for health.

From Science Daily: Sitting for long periods increases risk of disease and early death, regardless of exercise

The amount of time a person sits during the day is associated with a higher risk of heart disease, diabetes, cancer, and death, regardless of regular exercise, according to a review study.

"More than one half of an average person's day is spent being sedentary -- sitting, watching television, or working at a computer," said Dr. David Alter, Senior Scientist, Toronto Rehab, University Health Network (UHN), and Institute for Clinical Evaluative Sciences. "Our study finds that despite the health-enhancing benefits of physical activity, this alone may not be enough to reduce the risk for disease." The meta-analysis study reviewed studies focused on sedentary behaviour.

The authors found the negative effects of sitting time on health, however, are more pronounced among those who do little or no exercise than among those who participate in higher amounts of exercise."The findings suggest that the health risk of sitting too much is less pronounced when physical activity is increased," said Biswas. 

In the interim, Dr. Alter underlines strategies people can use to reduce sitting time. The target is to decrease sedentary time by two to three hours in a 12-hour day...For example, at work, stand up or move for one to three minutes every half hour; and when watching television, stand or exercise during commercials."

Research study after research study finds all sorts of health benefits from exercise. But what about the air quality in those stuffy crowded gyms, especially those in already polluted areas? From November 2014 NY Times:

The Bad Air in Our Gyms

But a new study of air quality in gyms raises some interesting questions about whether the places in which we work out are as healthy as they should be. Science and common sense tell us that exercising in polluted air is undesirable. People who frequently run alongside heavily trafficked freeways and breathe great lungfuls of exhaust have been shown to have an increased risk of heart disease, even if they are otherwise in admirably good shape.

...researchers at the University of Lisbon in Portugal and the Delft University of Technology in the Netherlands decided that they would place air-quality monitoring equipment in gyms throughout LisbonPortuguese fitness sites are similar to those in the United States, said Carla Ramos, a graduate student at the University of Lisbon who led the new study. Most feature a weight room and multiple, smaller studio spaces for aerobics classes, yoga sessions and similar programs.

For the new study, Ms. Ramos obtained permission from 11 Lisbon gyms to position air-quality monitors in each site’s weight room and several studios. The machines were set to measure pollutants during the late afternoon or evening hours, when the gyms were at their most crowded. For about two hours at each gym, the monitors measured the levels of commonly found indoor pollutants. These include carbon monoxide, carbon dioxide, ozone, airborne particulates such as dust, and various chemicals released by carpeting, cleaning products, furniture or paint, including formaldehyde.

To gain even more detailed readings, the scientists subsequently placed additional monitors in three of the gyms, which measured air quality throughout the building and throughout the entire day.Then they checked the pollutant levels from all of the gyms.

Their findings were disquieting. In general, the gyms showed high levels of airborne dust, formaldehyde and carbon dioxide. The concentrations of these substances generally exceeded most accepted standards for indoor air quality. (No government agency in the United States formally monitors air quality in gyms.) The levels were especially high during evening aerobics classes, when many people were packed into small studios, stirring up dust and fumes and puffing heavily, producing carbon dioxide with every breath.

The high concentrations of dust and chemicals like formaldehyde in the air at the gyms represent perhaps the greatest potential concern, Ms. Ramos said. In sufficient concentrations, these substances can contribute to asthma and other respiratory problems, she said. Almost all of the gyms in the study had levels of these substances that significantly exceed European standards for healthy indoor air standards.

Carbon dioxide, though not toxic to people, could also be cause for concern. In high concentrations, Ms. Ramos said, it has been found to contribute to bodily fatigue and cognitive fogginess, neither of which is desirable during a high-intensity aerobics class. Elevated levels of carbon dioxide can also indicate a poorly ventilated building, she said, especially if they remain inflated for hours, as they did in her study.

“We consider that the gymnasiums meet the criteria for a poor indoor quality,” Ms. Ramos said. Poor indoor air quality is a particular issue in gyms, of course, because people there tend to be breathing heavily. “When we exercise, we take in more air with each breath and most of that air goes through the mouth, bypassing the natural filtration system” in the nostrils, Ms. Ramos said. “The pollutants go deeper into the lungs compared to resting situations.”

The findings should not, however, discourage anyone from visiting a gym, Ms. Ramos said. None of the sites in the study had measurable levels of carbon monoxide, she pointed out, one of the most dangerous of known air pollutants.

Inactivity is more deadly than obesity. From Medscape:

Inactivity More Deadly Than Obesity, Large New Study Finds

Fresh evidence that just a little bit of exercise, such as 20 minutes walking a day, is extremely beneficial — regardless of whether people are overweight/obese or not — has emerged from a large European study.

In fact, the most pronounced reduction in premature death risk was observed among individuals who were normal weight/abdominally lean and "moderately inactive," compared with those of the same build who were completely inactive, which was defined as having a sedentary job with no reported recreational physical activity.

Looking at this another way, the study — in more than 330,000 men and women — showed that twice as many premature deaths may be attributable to lack of physical activity compared with the number of deaths attributable to obesity, the researchers say.

"This is a simple message: just a small amount of physical activity each day could have substantial health benefits for people who are physically inactive," said Dr Ekelund in a statement. "Although we found that just 20 minutes would make a difference, we should really be looking to do more than this — physical activity has many proven health benefits and should be an important part of our daily life," he added.

So they set out to examine the relationship between physical activity and all-cause mortality and to look at whether BMI and waist circumference modified these associations in a large sample of 334,161 men and women followed for more than 12 years... Just under a quarter (22.7%) of participants were categorized as inactive, reporting no recreational activity in combination with a sedentary occupation.

Over the 12 years of follow-up, 21,438 participants died.The greatest reduction in risk for premature death occurred in the comparison between inactive and moderately inactive groupsAll-cause mortality was reduced by 16% to 30% in the moderately inactive group compared with those categorized as inactive, across all strata of BMI and waist circumference.

The authors estimate that doing exercise equivalent to just a 20-minute brisk walk each day — burning between 90 and 110 kcal — would take an individual from the inactive to moderately inactive group and thereby reduce the risk for premature death by this same amount (ie, between 16% and 30%).

The impact was greatest among normal-weight individuals, but even those with higher BMI saw a benefit of physical activity.

This wonderful opinion piece is by Dr. John Mandrola, a cardiologist who also posts on his own blog at http://www.drjohnm.org/ . The bottom line: lifestyle is more important than drugs in preventing heart disease. The following is from Medscape:

Heart Disease and Lifestyle: Why Are Doctors in Denial?

I think and write a lot about the role of lifestyle choices as a treatment strategy. As an endurance athlete, I know that exercise, diet, sleep, and finding balance in life are the key components of success. It is the same in cardiology.

In a randomized controlled trial of primary prevention, no cardiologist would want to be compared against a good physical trainer or nutritionist. We would get trounced. Our calcium scores, biomarkers, pills, and procedures would not stand a chance. The study would be terminated early due to obvious superiority of lifestyle coaching over doctoring—which would blunt the true treatment effect and make us look less bad. (Wink to my epidemiology friends.)

I write a post about new oral anticoagulant drugs or statins or AF ablation, and people pay attention. You see it in the traffic. It's the same story at medical meetings: sessions on drugs and procedures draw the crowds. Late-breaking studies rarely involve the role of exercise or eating well. Exercise, diet, and going to bed on time have no corporate backing. The task of drawing attention to the basics is getting harder, not easier.

And this is our problem. I believe the collective denial of lifestyle disease is the reason cardiology is in an innovation rut. This denial is not active or overt. It is indolent and apathetic. Bulging waistlines, thick necks, sagging muscles, and waddling gaits have begun to look like normal. During the electronic medical record (EMR) click-fest after seeing a patient, I rarely click on "normal" physical exam. The general appearance is abnormal—either overweight or obese.

This is how I see modern cardiology. Our tricks can no longer overcome eating too much and moving too little. We approach health but never get there. If you waddle, snore at night, and cannot see your toes while standing, how much will a statin or ACE inhibitor or even LCZ696 help?

In fact, a reasonable person could make an argument that our pills and procedures might be making patients sicker.

When I started electrophysiology, I mostly treated people with fluky problems. My ablation procedures were on people with supraventricular tachycardia (SVT) due to aberrant pathways. My devices were mostly pacemakers in the elderly—a disease due to aging. These sorts of problems are (mostly) independent of how many sugar-sweetened beverages one drinks.

Now it is different. My practice is dominated by atrial arrhythmia—a disease now recognized as being due (in large part) to excesses of life, such as obesity, high blood pressure, sleep disorders, and overindulgence in alcohol. In other words: unnecessary. I make hundreds of dollars putting a hundred burns in a left atrium for a disease that a poorly paid physical trainer might prevent or treat. This has become cardiology writ large.

But the thing I cannot get over is that I am doctor, not a proceduralist. I am tasked with helping people be well. I fail in that task if I ignore the most effective and safest treatment option. I fail if I take the easy path. The prescription pad is easy. The EP lab is easy. The truth is hard... New anticoagulant drugs are easy. Ablation technology is easy. Statins are even easier. The truth—nutrition, exercise, balance in life—is hard.

Exercise is the Fountain of Youth? Note that they could not come up with a biomarker of aging in these active people. From Medical Xpress;

Exercise allows you to age optimally

Staying active allows you to age optimally, according to a study by King's College London and the University of Birmingham. The study of amateur older cyclists found that many had levels of physiological function that would place them at a much younger age compared to the general population; debunking the common assumption that ageing automatically makes you more frail.

The study, published in The Journal of Physiology, recruited 84 male and 41 female cycling enthusiasts aged 55 to 79 to explore how the ageing process affects the human body, and whether specific physiological markers can be used to determine your age.

Cyclists were recruited to exclude the effects of a sedentary lifestyle, which can aggravate health problems and cause changes in the body, which might appear to be due to the ageing process. Men and women had to be able to cycle 100 km in under 6.5 hours and 60 km in 5.5 hours, respectively, to be included in the study...Participants underwent two days of laboratory testing at King's. For each participant, a physiological profile was established which included measures of cardiovascular, respiratory, neuromuscular, metabolic, endocrine and cognitive functions, bone strength, and health and well-being. Volunteers' reflexes, muscle strength, oxygen uptake during exercise and peak explosive cycling power were determined.

The results of the study showed that in these individuals, the effects of ageing were far from obvious. Indeed, people of different ages could have similar levels of function such as muscle strength, lung power and exercise capacity. The maximum rate of oxygen consumption showed the closest association with age, but even this marker could not identify with any degree of accuracy the age of any given individual, which would be the requirement for any useful biomarker of ageing.

In a basic, but important test of function in older people, the time taken to stand from a chair, walk three metres, turn, walk back and sit down was also measured. Taking more than 15 seconds to complete the task generally indicates a high risk of falling. Even the oldest participants in the present study fell well below these levels, fitting well within the norm for healthy young adults.

Overall, the study concluded that ageing is likely to be a highly individualist phenomenon...The main problem facing health research is that in modern societies the majority of the population is inactive. A sedentary lifestyle causes physiological problems at any age. Hence the confusion as to how much the decline in bodily functions is due to the natural ageing process and how much is due to the combined effects of ageing and inactivity."

"In many models of ageing lifespan is the primary measure, but in human beings this is arguably less important than the consequences of deterioration in health. Healthy life expectancy - our healthspan - is not keeping pace with the average lifespan, and the years we spend with poor health and disabilities in old age are growing."

Emeritus Professor Norman Lazarus, a member of the King's team and also a cyclist, said: "Inevitably, our bodies will experience some decline with age, but staying physically active can buy you extra years of function compared to sedentary people. Cycling not only keeps you mentally alert, but requires the vigorous use of many of the body's key systems, such as your muscles, heart and lungs which you need for maintaining health and for reducing the risks associated with numerous diseases."

Another excellent reason to start walking more and increasing daily physical activity. So get out there and walk, walk, walk...

From Science Daily: Significant link between daily physical activity, vascular health

As millions of Americans resolve to live healthier lives in 2015, research from the University of Missouri School of Medicine shows just how important diligent, daily physical activity is. The researchers found that reducing daily physical activity for even a few days leads to decreases in the function of the inner lining of blood vessels in the legs of young, healthy subjects causing vascular dysfunction that can have prolonged effects.

Paul Fadel, associate professor of medical pharmacology and physiology, and John Thyfault, associate professor of nutrition and exercise physiology, also found that the vascular dysfunction induced by five days of inactivity requires more than one day of returning to physical activity and taking at least 10,000 steps a day to improve.

"We know the negative consequences from not engaging in physical activity can be reversed," said Fadel. "There is much data to indicate that at any stage of a disease, and at any time in your life, you can get active and prolong your life. However, we found that skipping just five days of physical activity causes damage to blood vessels in the legs that can take a prolonged period of time to repair."

"Inactivity is typically going to lead to people being overweight and obese," said Fadel. "The next step after that is insulin resistance which leads to Type 2 diabetes and cardiovascular disease."

The researchers studied the early effects on the body's blood vessels when someone transitions from high daily physical activity -- 10,000 or more steps per day -- to low daily physical activity, less than 5,000 steps per day. Five thousand steps is the national average, but only half of the daily recommendation from the U.S. Surgeon General. The researchers found going from high to low levels of daily physical activity for just five days decreases the function of the inner lining of the blood vessels in the legs.

Counting steps and daily physical activity is different than defined exercise, such as working out at the gym. While there are significant benefits to defined exercise, Thyfault and Fadel's research is based on what amounts to 30 minutes of moderate activity per day.

Research on a burning question for middle-aged men: how to control the belly fat that comes with aging? From Science Daily:

Weight training appears key to controlling belly fat

Healthy men who did 20 minutes of daily weight training had less of an increase in age-related abdominal fat compared with men who spent the same amount of time doing aerobic activities, according to a new study. Combining weight training and aerobic activity led to the most optimal results. Aerobic exercise by itself was associated with less weight gain compared with weight training.

"Because aging is associated with sarcopenia, the loss of skeletal muscle mass, relying on body weight alone is insufficient for the study of healthy aging," said lead author Rania Mekary, a researcher in HSPH's Department of Nutrition. "Measuring waist circumference is a better indicator of healthy body composition among older adults. Engaging in resistance training or, ideally, combining it with aerobic exercise could help older adults lessen abdominal fat while increasing or preserving muscle mass."

The new study was long-term with a large sample of healthy men with a wide range of BMI (body mass index). Mekary and colleagues studied the physical activity, waist circumference (in centimeters (cm)), and body weight of 10,500 healthy U.S. men aged 40 and over participating in the Health Professionals Follow-up Study between 1996 and 2008.

Their analysis included a comparison of changes in participants' activity levels over the 12-year period to see which activities had the most effect on the men's waistlines. Those who increased the amount of time spent in weight training by 20 minutes a day had less gain in their waistline (-0.67 cm) compared with men who similarly increased the amount of time they spent on moderate-to-vigorous aerobic exercise (-0.33 cm), and yard work or stair climbing (-0.16 cm). Those who increased their sedentary behaviors, such as TV watching, had a larger gain in their waistline.

The bottom line: for better health be physically active at least is 2.5 hours of week. Note that HbA1c is a measure of glycated hemoglobin which identifies average plasma glucose concentration (and lower is better). From Medscape:

Exercise Tied to Cardiometabolic Markers in Clinic Patients 

Healthy, middle-aged outpatients who were physically active for at least 2.5 hours a week had better blood pressure and blood glucose levels than their sedentary peers in a large cross-sectional study in California. The differences were especially notable in women, in this study published online December 18, 2014 in Preventing Chronic Disease.

Men and women who were consistently physically active—defined as performing moderate to vigorous activity such as brisk walking for at least 150 minutes a week, as self-reported at all three outpatient visits in a 33-month period—had lower diastolic blood pressure, glucose, and HbA1c levels than patients not reporting exercise at that level.

Moreover, on a population level, the observed associations "were comparable to those needed to reduce the risk of coronary heart disease, stroke, and diabetes," they continue. "If healthcare providers would routinely assess the physical activity of their patients and refer those who are physically inactive to effective physical-activity programs, it may reduce the burden of future chronic diseases."

They analyzed electronic records from over 622,000 adults covered by Kaiser Permanente Southern California healthcare insurance who made at least three clinic visits between April 2010 and December 2012 and were not being treated for diabetes or hypertension.

The consistently active women had systolic and diastolic blood pressures that were 4.60-mm-Hg lower and 3.28-mm-Hg lower, respectively, than inactive women. Perhaps surprisingly, somewhat active women had slightly better blood-pressure values than the more active group.

Another popular view bites the dust.

From the NY Times: Why Antioxidants Don’t Belong in Your Workout

Antioxidant vitamins are enormously popular with people who exercise. The supplements are thought to alleviate muscle damage and amplify the effects of exercise. But recent studies have raised questions about whether antioxidants might be counterproductive for runners and other endurance athletes. And now a cautionary new experiment adds to those doubts by finding that antioxidants may also reduce the benefits of weight training.

 Both aerobic exercise and strength training lead to the production of free radicals, molecules that in concentrated amounts can cause tissue damage. Antioxidants sop up and neutralize free radicals. So, the thinking goes, taking antioxidant should lessen some of the damage and soreness after exercise and allow people to train harder.But recent experiments with endurance athletes have found that consuming large doses of vitamins C and E actually results in a slightly smaller training response. 

So for the new study, which was published online this month in The Journal of Physiology, scientists at the Norwegian School of Sports Sciences in Oslo and other institutions, some of whom previously had studied aerobic exercise and antioxidants, set out to repeat those experiments in a weight room.

They began by recruiting 32 men and women who had at least some experience with weight training. They measured the volunteers’ muscular size and strength.Then they randomly divided them into two groups. Half were asked to start taking two antioxidant vitamin pills each day, one before and one after exercising. The total daily dosage amounted to 1,000 milligrams of Vitamin C and 235 milligrams of Vitamin E, which “is high but not higher than athletes commonly use,” ...The other group did not take any supplements.

All of the volunteers then began the same resistance-training regimen, consisting of four fairly rigorous training sessions each week. As the exercises grew easy, weights were increased, with the aim of pumping up the size and strength of the volunteers’ muscles.The program lasted 10 weeks. 

In general, people’s muscles had increased in size to the same extent, proportionally. The group that had taken the vitamins now had larger muscles. So did the group that had not. But there were subtle but significant differences in their strength gains. Over all, the volunteers who had taken the antioxidants had not added as much strength as the control group. Their muscles were punier, although they had grown in size.

The differences continued beneath the skin, where, as the muscle biopsies showed, the volunteers taking the vitamins had reduced levels of substances known to initiate protein synthesis. Protein synthesis is necessary to repair and strengthen muscles after weight training. So the volunteers taking the vitamins were getting less overall response from their muscles, even though they were following the same exercise program.

Exactly how antioxidant pills change muscles’ reactions to weight training is still unknown. But Dr. Goran and his colleagues speculate that, by reducing the number of free radicals after exercise, the vitamins short-circuit vital physiological processes. In this scenario, free radicals are not harmful molecules but essential messengers that inform cells to start pumping out proteins and other substances needed to improve strength and fitness. Without enough free radicals, you get less overall response to exercise.

The upshot is that whether you lift weights or jog, Dr. Goran would advise “against the use of high-dosages of concentrated antioxidant supplements.”

Jogging? Now retirees planning to relax and putter around instead have to jog for health? From Science Daily:

Jogging keeps you young: Seniors who run regularly can walk as efficiently as 20-somethings

A new study by researchers at Humboldt State University and the University of Colorado, Boulder is shedding light on an unexpected benefit of jogging in older adults. The study looked at adults over the age of 65 -- some of whom walk for exercise and some who run for exercise. The researchers found that those who run at least 30 minutes, three times a week were less likely to experience age-related physical decline in walking efficiency than those who simply walked.

In fact, the older runners were 7-10 percent more efficient at walking than those who didn't jog. "What we found is that older adults who regularly participate in high aerobic activities -- running in particular -- have what we call a lower metabolic cost of walking than older, sedentary adults. In fact, their metabolic cost of walking is similar to young adults in their 20s," said Justus Ortega, a Kinesiology Professor at Humboldt State and director of HSU's Biomechanics Lab.

Metabolic cost is the amount of energy needed to move and naturally increases as we age. High metabolic cost contributes to making walking more difficult and tiring. Decline in walking ability is a key predictor of morbidity in older adults.

In the study, researchers looked at self-reported older joggers over the age of 65 -- those who ran at least 30 minutes a day, three times a week -- and self-reported walkers, those who walked three times a week for 30 minutes. Participants were asked to walk on a treadmill at three speeds (1.6, 2.8 and 3.9 miles per hour) as researchers measured their oxygen consumption and carbon dioxide production. Overall, older joggers were 7-10 percent more efficient at walking than older adults who just walked for exercise. Their metabolic cost was similar to young people in their 20s.

Researchers aren't yet sure what makes joggers more efficient than walkers but they believe it may have something to do with the mitochondria found in cells. Evidence suggests that people who exercise vigorously have healthier mitochondria in their muscles.

 And a related concern: what about my knees? From  Science Daily:

Running does not lead to knee osteoarthritis, may protect people from developing disease, experts say

Running as a habitual exercise at any stage in life not only does not increase a person’s risk of developing knee osteoarthritis and may even help protect a person from developing the painful disease, according to new research findings."This {research} does not address the question of whether or not running is harmful to people who have pre-existing knee OA," said Dr. Lo. "However, in people who do not have knee OA, there is no reason to restrict participation in habitual running at any time in life from the perspective that it does not appear to be harmful to the knee joint."