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Standing and exercise linked to lower odds of obesity

Standing for at least one-quarter of the day has been linked to lower odds of obesity in a new study led by the American Cancer Society in collaboration with The Cooper Institute, the University of Texas, and the University of Georgia. The study appears inMayo Clinic Proceedings.

While sedentary behavior (such as watching TV and commuting time) has been linked to negative health effects, it is unclear whether more time spent standing has protective health benefits. To investigate further, a research team led by Dr. Kerem Shuval, Director of Physical Activity & Nutrition Research at the American Cancer Society, examined reported standing habits in relation to objectively measured obesity and metabolic risk among more than 7000 adult patients attending the Cooper Clinic (Dallas, Texas) for preventive medicine visits from 2010 to 2015. Specifically, the association between standing time and obesity was determined through three measures: body mass index (BMI), body fat percentage, and waist circumference. The association between standing and metabolic risk was assessed via metabolic syndrome, a clustering of risk factors that increase the risk for heart disease, stroke, and diabetes.

The study found that among men, standing a quarter of the time was linked to a 32% reduced likelihood of obesity (body fat percentage). Standing half the time was associated with a 59% reduced likelihood of obesity. But standing more than three-quarters of the time was not associated with a lower risk of obesity.

In women, standing a quarter, half, and three quarters of the time was associated with 35%, 47%, and 57% respective reductions in the likelihood of abdominal obesity (waist circumference). No relationship between standing and metabolic syndrome was found among women or men.

Researchers also investigated whether physical activity in conjunction with standing provided additional reduction in risk. They found that among those meeting physical activity guidelines (150 minutes of moderate activity and/or 75 minutes of vigorous activity per day) the addition of standing time was associated with incremental drops in the likelihood of all obesity measures and metabolic syndrome in both women and men. For example, men meeting physical activity guidelines and standing a quarter to half of the time had a 57% reduced likelihood for abdominal obesity, whereas those meeting guidelines and standing three quarters of the time or more had a 64% lower odds for abdominal obesity.

While the findings provide initial and important evidence on the potential protective benefits of standing, the study team cautions that their findings should be interpreted in the context of the study’s limitations. These findings are cross-sectional, meaning they capture a ‘snapshot’ in time, so it is unclear whether less standing leads to more obesity or whether in fact obese individuals stand less. Additional prospective studies are needed to determine whether standing has protective health benefits.

Moreover, while obesity and metabolic syndrome were objectively measured, standing and physical activity were not; they were based on self-report which may lead to over estimation of these behaviors. Further, due to the survey measure used in the study, it is unclear whether study participants were standing still or standing and moving. While standing and moving provides extra energy expenditure, standing still is similar to sitting with regards to energy expenditure.

Finally, it should be noted that some studies have found adverse health effects to prolonged standing, such as increased risk for varicose veins. Therefore, additional research into the effects of standing on health is definitely suggested.

Date: November 3, 2015

Source: University of Kent

University of Kent. “Endurance expert: Drugs could help ‘lazy’ people exercise: In what has been described as ‘doping for lazy people’ an endurance expert advocates psychoactive drugs to encourage sedentary people to exercise.” ScienceDaily. ScienceDaily, 3 November 2015. <www.sciencedaily.com/releases/2015/11/151103140442.htm>.

Endurance expert: Drugs could help ‘lazy’ people exercise

Endurance expert suggests drugs could help ‘lazy people’ exercise In what has been described as ‘doping for lazy people’ a University of Kent endurance expert has advocated the use of psychoactive drugs to encourage sedentary people to exercise.

Together with lack of time, physical exertion is one of the main perceived barriers to exercise. This is not surprising because humans evolved to be ‘lazy’, i.e. to conserve energy. Professor Samuele Marcora suggests that reducing perception of effort during exercise using caffeine or other psychoactive drugs (e.g. methylphenidate and modafinil) could help many people stick to their fitness plans.

Whilst acknowledging that such an intervention is both drastic and controversial, Professor Marcora points out that perception of effort is one of the main reasons why most people choose sedentary activities for their leisure time. Compared to watching television (zero effort), even moderate-intensity physical activities like walking require considerable effort. He says finding a way that makes people with very low motivation to do even moderate exercise, like walking, could be particularly useful.

Similarly, a reduction in perception of effort would be very helpful to the many people who find exercise difficult because they are overweight and/or exercise after work in a state of mental fatigue.

Professor Marcora also states that whilst there is no strong ethical opposition to the use of psychoactive drugs to help quit smoking (nicotine) or treat obesity (appetite suppressants), the negative perception of doping in sport may prevent the use of stimulants and other psychoactive drugs to treat physical inactivity.

Given that physical inactivity is responsible for twice as many deaths as obesity, he hopes that psychopharmacological treatment for physical inactivity will be considered fairly and seriously rather than immediately rejected on the basis of unrelated ethical considerations about doping in sport.

Professor Samuele Marcora is Director of Research at the University of Kent’s School of Sport and Exercise Sciences. His paper Can Doping be a Good Thing? Using Psychoactive Drugs to Facilitate Physical Activity Behaviour has been published in the journal Sports Medicine.

Source: University of Kent article, “Endurance expert: Drugs could help ‘lazy’ people exercise: In what has been described as ‘doping for lazy people’ an endurance expert advocates psychoactive drugs to encourage sedentary people to exercise.” Science Daily, 3 November 2015.

Low energy sweeteners help reduce energy intake and body weight, evidence shows

Source: University of Bristol

Summary: Use of low energy sweeteners (LES) in place of sugar, in children and adults, leads to reduced calorie intake and body weight – and possibly also when comparing LES beverages to water — according to a new review.

Use of low energy sweeteners (LES) in place of sugar, in children and adults, leads to reduced calorie intake and body weight — and possibly also when comparing LES beverages to water — according to a review led by researchers at the University of Bristol published in the International Journal of Obesity.

For the first time, all available science was integrated into a single review to evaluate the real impact of LES, such as saccharin, aspartame, sucralose and stevia, on energy intake (EI) and body weight (BW) over the short- and long-term. A considerable weight of evidence confirmed that consuming LES instead of sugar helps reduce relative energy intake and body weight.

Lead author Professor Peter Rogers from the University of Bristol said: “We believe that we should shift the question from whether LES are ‘good’ or ‘bad,’ and rather focus on how they should be best used in practice to help in the achievement of specific public health goals, such as the reduction of intakes of free sugars and energy.”

The authors conducted systematic reviews of relevant studies in animals and humans consuming LES in a non-restricted diet. In total, 12 human prospective cohort studies, 228 comparisons in human intervention studies (short and long-term) and 90 animal studies were examined.

Managing energy balance (that is, energy intake vs. energy expenditure) well results in a steady body weight. On the contrary, eating an excessive amount of food causes an increase in body weight as this extra energy is stored in the body as adipose tissue (fat). Low energy sweeteners were developed for consumers looking for ways to reduce their sugar and energy intake.

The comparison between LES beverages and water is important because it shows that LES do not increase appetite. If anything, the evidence suggests that LES beverages reduced weight more than water. One reason for this may be that switching from sugar-sweetened drinks to those with LES may be an easier and more acceptable dietary change to make than switching to water.