Choosing to Lead an Inactive Life Means Paying the Price for that Choice
It is no great secret that, all other things being equal, people who are some combination of less fit, less active, and more overweight suffer from a greater incidence of age-related health issues and have a shorter life expectancy. They also pay a higher lifetime cost for medical treatment despite that shorter life expectancy. A century of medical studies on this topic demonstrate these points quite comprehensively. Much as some sedentary or overweight people like to hear that their choices do not have serious consequences, this is not the case - they do have serious consequences. Yes, it is harder to stay thin and active in this age of ease of transport and more calories than any individual can possibly work their way through. Yes, it is easier to postpone exercise indefinitely and eat whatever you feel like eating. Nonetheless, this is all still a matter of choice. Those thinner people you see walking around out there? Those physiques didn't happen by accident. Choose to swing the odds towards a healthier, longer future, or choose to swing the odds towards a less healthy, shorter future: it is up to you.
If this was an age of stasis, in which medicine was not advancing at a very rapid pace, one might make the nihilist's argument that we'll all end up in the same place in the end, and that it is a person's free choice to consume for pleasure now at the cost of suffering later. Kicking the can down the line is a human specialty, after all. But we do live in an age of rapid progress in biotechnology, in which practical, working rejuvenation therapies will emerge over the decades ahead. In this environment, a few years here and a few years there do matter. Postponing the decline of old age to the best reasonable extent possible with the limited but freely available and reliable tools of today, meaning exercise and calorie restriction, might make a very large difference in the end - the difference between living to benefit significantly from rejuvenation treatments, or missing out on that era. Consider the odds. Perhaps science will advance enough to rescue you from any additional harms you do to yourself above and beyond those inflicted by aging, but why roll the dice if you don't have to?
For today's glance at the scientific world, look below to see a brace of references to recent studies on activity levels and age-related disease. They recapitulate thin slices of what is already well known about exercise, fat tissue, and health, but there seems to be an endless font of funding for the increasingly details quantification of exercise and its effects. Why this must be the case, whilst researchers working on genuinely new medical science find it ever a struggle to obtain grants, is a question with no satisfactory answer. If we lived in a better world, there would be a great deal more funding for the new and the experimental aimed at cures, when considered in comparison to the work of finely cataloging the present state of health and operation of the human machine absent those cures.
Physical inactivity and sedentary behaviors are associated with cardiometabolic risk factors
Previous studies of healthy adults and persons with diabetes have demonstrated that physical activity - particularly activities with moderate-high intensity - and daily sedentary behaviors, such as watching television, have a significant effect on cardiometabolic health. Nevertheless, these observations have never been explored in older adults at high cardiovascular risk, a typically sedentary and physically inactive population that has a high risk of developing chronic diseases. Consequently, researchers implemented the PREDIMED-PLUS trial and thus address this question by evaluating different types of physical activities and sedentary behaviors in a population of 5,576 men and women with high cardiovascular risk. They have also studied the effect of replacing the time spent watching television with the same time engaging physical activities with different intensities.
The most striking results from this investigation show that increasing the time spent on physical activities with moderate-high intensity (brisk walking, climbing stairs, working in the garden or performing sports) by one hour a day was associated with a 3%-6% increase in protection against obesity, diabetes, abdominal obesity and low HDL-cholesterol. In contrast, increasing the time spent watching television by one hour a day was associated with an increased presence of these cardiometabolic risk factors. Moreover, when one hour a day of watching television was replaced by one hour a day of physical activity with moderate-high intensity, the protection against these cardiometabiloc risk factors was even greater (3%-9%) than the protection observed when each activity was evaluated separately.
Overweight, obese people risk heart disease at younger ages
In a new study, overweight and obese people tended to have slightly shorter or similar lifespans compared to people with normal body weight, whether or not they had cardiovascular diseases. But compared to people with normal BMI, lifetime risks for developing cardiovascular disease were higher in overweight and obese adults. For example, overweight middle-aged women were 32 percent more likely to develop cardiovascular disease in their lifetime compared to those of normal weight. Average years lived without cardiovascular disease were longest for people with normal BMI, while years lived with cardiovascular disease were longest for overweight and obese people.
Overweight or obese people also experienced cardiovascular disease at an earlier age than those with normal BMI. For example, among overweight middle-aged women, cardiovascular disease began 1.8 years earlier than normal weight women, and 4.3 years earlier for those who were obese. For the study, the researchers looked at cardiovascular disease data of 72,490 people, focusing on patients in middle-age, who were 55-years-old on average. Participants were healthy and free of cardiovascular disease when they enrolled in the study. The average BMI was 27.4 for men and 27.1 for women. "Our findings suggest that healthcare providers need to continue to be aware of the increased risk of earlier cardiovascular disease faced by overweight and obese people. Healthcare providers should emphasize the importance of maintaining healthy weight throughout their lives to live longer, healthier lives."
Prolonged sedentary time and physical fitness among Canadian men and women aged 60 to 69
This study examined associations between sedentary time and fitness among Canadians in their sixties. The main findings were that, after adjusting for moderate-to-vigorous physical activity (MVPA): 1) objectively measured sedentary time was inversely associated with cardiorespiratory fitness and grip strength; 2) the number of breaks in sedentary time was positively associated with cardiorespiratory fitness; 3) the percentage of sedentary time spent in bouts of at least 20 minutes was inversely associated with cardiorespiratory fitness; 4) associations between sedentary time in bouts of at least 20 minutes and breaks in sedentary time and cardiorespiratory fitness were not consistent between sexes, nor were associations between sedentary time and grip strength; and 5) self-reported sedentary time was not related to any fitness variable. The last conforms with previous work showing measured sedentary time to be more consistently related to health outcomes than are self-reported measures.Note
Earlier research indicates that sedentary time and patterns of sedentary time are associated with older adults' health and functional fitness. In the present study, the percentage of total sedentary time spent in bouts of at least 20 minutes was inversely associated with cardiorespiratory fitness, and a greater number of breaks in sedentary time was associated with better cardiorespiratory fitness. These findings are important because cardiorespiratory fitness is a strong predictor of morbidity and all-cause mortality. In 2015, it was demonstrated that non-exercising older adults with higher cardiorespiratory fitness have better vascular function and lower cardiovascular risk. It was suggested that greater amounts of non-exercise activity, such as activities of daily living, may partly explain the fitness and vascular health of some older individuals who do not engage in purposeful physical actvity. It is possible that adaptations in the vasculature, and likely other components such as muscle oxidative capacity, are stimulated by light intensity activities.
Total sedentary time was inversely related to grip strength in men and women, even after adjusting for MVPA. As well, the association between breaks in sedentary time and sit-and-reach scores was positive among men. Therefore, sedentary time may also influence musculoskeletal fitness, which is crucial for independent living and autonomy. These data demonstrate a significant relationship between directly measured sedentary time, breaks in sedentary time, and fitness among Canadians in their sixties. Given long-established associations between fitness and both health and functional autonomy for older adults, this study underscores the importance of minimizing total sedentary time and breaking up sedentary time, in addition to increasing physical activity.
Older adults who exercise regularly may lower chances for severe mobility problems
Based on the proven health benefits of exercise for older adults, a team of researchers theorized that exercise might also help adults prevent or delay disabilities that interfere with independent living. The researchers enrolled 1,635 adults between the ages of 70 and 89. All of the participants were at high-risk for becoming physically disabled. At the beginning of the study, the participants were able to walk about five city blocks (one-quarter of a mile) without assistance. The participants were split into two groups. One group was encouraged to exercise regularly. In addition to taking a daily 30-minute walk, they performed balance training and muscle strengthening exercises. The other group attended weekly workshops for 26 weeks, followed by monthly sessions. The workshops provided information about accessing the healthcare system, traveling safely, getting health screenings, and finding reliable sources for health and nutrition education. The workshop instructors also led the participants in 5- to 10-minute flexibility or stretching exercise sessions. Researchers gave all participants thorough tests for disability at the beginning of the study and then at 6, 12, 24, and 36 months after the study started. The researchers reported that people in both groups experienced about the same level of disability after the study. However, people in the exercise group experienced a lower level of severe mobility problems than did people who attended the health workshops.
What about conflicting evidence that purports to show that these studies are genetically confounded?
See e.g.
https://jaymans.wordpress.com/2013/04/30/obesity-and-iq/
Why won't people listen? A good BBC article on this:
http://www.bbc.com/future/story/20170308-why-even-the-best-feedback-can-bring-out-the-worst-in-us