Category: Exercise

Categories : Cardiovascular Disease ExerciseTags :

Large Study Casts Doubt on “Fat but Fit”

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New Spanish research casts doubt on the “fat but fit” paradox, where it is thought that physical fitness is enough to eliminate cardiovascular disease (CVD) risk.

Overweight and obesity is a worldwide problem that is greatly contributing to the burden of noncommunicable diseases, including CVD. A high body mass index (BMI) is strongly associated with CVD risk factors, such as hypercholesterolaemia, hypertension and diabetes. The cardiovascular complications arising from overweight and obesity are driven by processes such as inflammation, insulin resistance, endothelial dysfunction, coronary calcification. Some evidence suggested that physical activity was cardioprotective, partly or completely eliminating the CVD risk from disease – the “fat but fit” paradox.

A recent meta-analysis showed that cardiovascular fitness was a better predictor of cardiovascular disease over overweight/obesity, suggesting that perhaps public health programmes should emphasise fitness over control of body weight. To this end, the researchers sought to confirm if the “fat but fit” paradox was real.

The researchers gathered data from workers’ health insurance, with participants aged 18-64 grouped into normal weight, overweight and obesity by BMI, and into regularly active ( >150 min moderate physical activity or equivalent per week), insufficiently active (less than regularly active) and inactive (no physical activity at all). They were further separated by age, sex, smoking status and residential address.

Approximately 42%, 41%, and 18% of participants had normal weight, overweight, or obesity, respectively; 63.5%, 12.3%, and 24.2% were inactive, insufficiently active, and regularly active; and 30%, 15%, and 3% had hypercholesterolaemia, hypertension, and diabetes.

However, the protective effect of physical activity was far less than the excess risk from overweight/obesity. So much so that even regularly active obese participants had two to five-fold risk increases over their inactive but normal weight peers in the risk factors.

The protective effect of physical activity in overweight/obesity remains controversial. Shortcomings of the study were that they did not control for diet, and only accounted for self-reported leisure time activities. However, the large study size, with over 500 000 participants, should put paid to the theory that a physically active lifestyle can completely eliminate the deleterious effects of overweight/obesity.

The researchers concluded that, “weight loss per se should remain a primary target for health policies aimed at reducing CVD risk in people with overweight/obesity.”

Journal article source: European Journal of Protective Cardiology

Journal information: Pedro L Valenzuela, et al., Joint association of physical activity and body mass index with cardiovascular risk: a nationwide population-based cross-sectional study, European Journal of Preventive Cardiology, 2021;, zwaa151, https://doi.org/10.1093/eurjpc/zwaa151

Categories : Exercise PaediatricsTags :

Coordination in Children Does Not Predict Aerobic Fitness

On By ModernMedia

Even though clumsy children find it hard to perform as well in sports that require a lot of coordination, they are no less aerobically fit than their more agile peers.

This finding comes from a new study from the Faculty of Sport and Health Sciences of the University of Jyväskylä and the Institute of Biomedicine of the University of Eastern Finland. The general view is that children who have poor motor coordination tend to be overweight and have a low level of aerobic fitness – but this turns out not to be the case.

The study participants consisted of 332 children aged 7 to 11 years, with the study’s aim being to explore the association between aerobic fitness, body fat content, and motor skills. A maximum bicycle ergometer test was used to measure aerobic fitness and bioimpedance and DXA devices measured body composition. Common methods were used to gauge motor skills.

Eero Haapala, PhD, Faculty of Sport and Health Sciences, University of Jyväskylä, said: “Our study clearly demonstrated that aerobic fitness is not linked to motor skills when body composition is properly taken into account.”

She added: “Also, aerobic fitness was not strongly associated with overweight or obesity. Therefore, it seems that the role of poor aerobic fitness as a risk factor for poor motor skills and excess body weight has been strongly exaggerated.”

Earlier studies had shown that varied physical exercise can develop motor skills, regardless of body weight or aerobic fitness, and that less sedentary behaviour and more exercise protects against becoming overweight.

“The key message of our study is that even a child who is unfit can be motorically adept and the heart of a clumsier kid can be as fit as her or his more skilful peer,” Haapala concluded. “In addition, high levels of varied physical activity and reduced sedentary behaviour are central to the development of motor skills and the prevention of excess weight gain since childhood.”

Source: News-Medical.Net

Journal information: Haapala, EA, Gao, Y, Lintu, N, et al. Associations between cardiorespiratory fitness, motor competence, and adiposity in children. Transl Sports Med. 2021; 4: 56– 64. https://doi.org/10.1002/tsm2.198

Categories : Diet and Nutrition ExerciseTags :

Poor Diet is an Important Factor of Childhood Obesity

On By ModernMedia

A Baylor University study has shown that market-bought food in addition to the traditional diet reliably predicted obesity in Amazonian children, a result that has important insights into the global childhood obesity epidemic.

Globally, 6% of girls and 8% of boys in 2016 were obese, compared to 1% in 1975. In South Africa, 13% of children under the age of five are obese.

“The importance of a poor diet versus low energy expenditure on the development of childhood obesity remains unclear,” said lead author Samuel Urlacher, PhD, of Baylor University. “Using gold-standard measures of energy expenditure, we show that relatively lean, rural forager-horticulturalist children in the Amazon spend approximately the same total number of calories each day as their much fatter peri-urban counterparts and, notably, even the same number of calories each day as children living in the industrialised United States.”

Factors such as income and access to running water were used to establish market integration. Children’s physical activity was measured with wearable devices and immune activity by measuring biomarkers obtained from minimally invasive finger-prick blood samples. Most importantly, children’s daily energy expenditure was measured with the “doubly labeled water” stable isotope-tracking method and children’s resting energy expenditure using respirometry. These are both participant-friendly, gold-standard techniques.

A third of peri-urban children were overweight, while zero rural children were, and peri-urban children on average had 65% more body fat than rural children. Peri-urban and rural children had similar levels of physical activity, and market integration, immune activity and physical activity had no effect on expenditure between rural and peri-urban children’s energy expenditure, in common with previous studies. Compared to rural children, peri-urban children spent 108 less calories while at rest, which is thought to be due to lower immune activity. Most importantly, variation in market foods was related to children’s level of body fat.

“Our findings are in line with a growing body of research pointing toward poor diet being the most important factor underlying the development of childhood obesity,” Urlacher said. “Exercise is absolutely still a critical part of this equation and is essential for living a healthy life, but diet increasingly appears to be most directly related to children’s adiposity and long-term energy balance.”

The researchers plan to follow the children longitudinally to record any development obesity and cardiovascular problems.

Source: News-Medical.Net

Categories : Ageing ExerciseTags :

Mid-life Exercise Positively Shapes Late-life Brain Structure

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That exercise in one’s middle years benefits health in later life is perhaps no surprise given our current understanding of its benefits, but and MRI study has shown to influence the brain’s structure in later years.

Using MRI scans, high levels (150 minutes per week or more) of self-reported moderate-to-high physical activity were associated with reduced risk of lacunar infarct in late life (OR 0.68, 95% CI 0.46-0.99) and more intact white matter integrity.

“Our study suggests that getting at least an hour and 15 minutes of moderate-to-vigorous intensity physical activity a week or more during midlife may be important throughout your lifetime for promoting brain health and preserving the actual structure of your brain,” said Priya Palta, PhD, of Columbia University Irving Medical Center. “In particular, engaging in more than 2 and a half hours of physical activity per week in middle age was associated with fewer signs of brain disease.”

There has been mixed evidence linking physical activity to brain measures or improvements in cognitive function. PhDs Nicole Spartano, of Boston University School of Medicine, and Leonardo Pantoni, MD, of University of Milan, noted in an accompanying editorial that the “most consistent evidence for the protective effect of physical activity against dementia risk has been reported to be leisure time physical activity, and it is unclear whether there is benefit to other types of physical activity that may be less ‘enriching.'”

“It is possible that future work will uncover the requirement that physical activity interventions to reduce dementia risk actually have an enriching element, such as in leisure-time activities, rather than be strictly rote, mechanical movement,” Spartano and Pantoni added.

Recruiting 1 604 individuals with a mean baseline age of 54, the participants had five examinations over 25 years and MRI at a mean age of 72. At baseline (1987-1989) and 25 years later, participants had their moderate-to-vigorous physical activity assessed in a questionnaire. 

At midlife, 11% had low levels of moderate-to-high intensity activity (1 to 74 minutes a week), 16% middle levels (75 to 149 minutes a week), and 39% high levels (150 minutes a week or more), with the remainder reporting none.

High moderate-to-vigorous midlife activity was associated with better white matter integrity in late life, compared with no moderate-to-vigorous midlife activity, but there was no association with grey matter volume.

While the risk of lacunar infarcts were lower with more intense midlife activity, risk of cortical infarcts or subcortical microhemorrhage were not. “The associations of greater levels of mid-life physical activity with fewer lacunar (but not cortical) infarcts and greater white matter microstructural integrity suggest cerebrovascular mechanisms are primarily at play,” Palta and colleagues wrote.

When adjusted for vascular risk factors, the association of midlife physical activity to lacunar infarcts was weakened, but the association with white matter microstructure. The editorialists said that it implies that “evidence from this study supports a hypothesis that the mechanisms linking physical activity and the brain are likely multi-dimensional, including mechanisms other than simply improving cerebrovascular health.” 

Late-life moderate-to-vigorous physical activity also was associated with most brain measures compared with no moderate-to-vigorous activity, but as this was a prospective study that spanned decades, the “association between midlife physical activity levels and later-life brain imaging features makes a much stronger case for causality than does the same relationship when measured only in late life,” the researchers noted.

The study had several limitations, which included using self-reported data, did not include non leisure-related activity, and participant attrition.

Source: MedPage Today

Journal information: Source Reference: Palta P, et al. A prospective analysis of leisure-time physical activity in midlife and beyond and brain damage on MRI in older adults, Neurology 2020; DOI: 10.1212/WNL.0000000000011375.

Categories : Ageing ExerciseTags :

Standing Protects against Heart Failure in Older Women

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A study examining elderly women’s amount of time spent sitting or standing has shown a marked increase in the risk for hospitalisation for heart failure.

The Women’s Health Initiative Observational Study followed 81 000 postmenopausal women for 9 years. None of the women had been diagnosed with heart failure and could walk at least one block unassisted, and they self-reported the amount of time they spent sitting or lying down. Over this time, 1402 women were hospitalised with heart failure.

The researchers graded the amount of sedentary time (sitting or lying down) into three categories: 6.5 hours or less; 6.6-9.5 hours; and more than 9.5 hours. Those who sat 9.5 hours or more experienced a 42% increase in the rate of heart failure compared to those who sat for 6.5 hours or less.

Lead author of the study,  Michael J LaMonte, PhD, MPH, research associate professor of epidemiology in the School of Public Health and Health Professions at the University at Buffalo in Buffalo, New York, said that there was a lack of data on sedentary time and heart failure, and even less so in elderly women.

“Our message is simple: sit less and move more. Historically, we have emphasised promoting a physically active lifestyle for heart health—and we should continue to do so! However, our study clearly shows that we also need to increase efforts to reduce daily sedentary time and encourage adults to frequently interrupt their sedentary time.” 

He added, “This does not necessarily require an extended bout of physical activity; it might simply be standing up for 5 minutes or standing and moving one’s feet in place. We do not have sufficient evidence on the best approach to recommend for interrupting sedentary time. However, accumulating data suggest that habitual activities such as steps taken during household and other activities of daily living are an important aspect of cardiovascular disease prevention and healthy aging.”

Source: Medical Xpress

Categories : ExerciseTags :

Study finds exercise intensity not linked to mortality in older adults

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Medical Express reports that a study published in The BMJ with 1567 participants prescribed high intensity interval training (HIIT) or  moderate intensity continuous training (MICT) to older adults, with surprising results.

The researchers found no difference in all cause mortality between the control group (4.7%, 37 participants) and combined HIIT and MICT group (4.5%, 35 participants).

They also found no differences in cardiovascular disease or cancer between the control group and the combined HIIT and MICT group.

For example, the total proportion of participants with cardiovascular disease after five years was 15.6%, with 16% (125 participants) in the control group, 15% (58 participants) in the MICT group, and 15.3% (61 participants) in the HIIT group.

“This study suggests that combined MICT and HIIT has no effect on all cause mortality compared with recommended physical activity levels,” write the researchers.