Childhood Obesity, Exercise and Heart Failure, Testosterone Supplements for Astronauts and More from the Journal Medicine & Science in Sports & Exercise®

Childhood Obesity, Cognition and Academics

Childhood obesity is a serious health concern in the United States and around the world. About one-third of children in the United States are believed to be overweight or obese. During childhood, it has been shown that obesity has harmful effects on the health of the heart (as well as the circulatory system) and other organs. New research suggests that obesity may also negatively impact brain health. In this study, researchers investigated the link between obesity and the amount of fat stored in the visceral area (VAT) with cognition and academics. VAT is stored around important organs in the abdomen. Measures of interest for a group of 8-9-year-old obese girls (n=55) were obtained and compared to those from an age- and fitness-matched group of normal-weight girls (n=55). The findings indicated that children with obesity had worse scores on reading and math tests compared to normal weight children. Having more VAT was related to poorer cognition in children with obesity. These findings suggest that children with obesity perform more poorly on academic tests than their normal-weight peers, and that for children with obesity, VAT is related with worse cognition. Thus, keeping a normal body weight and limiting fat in the stomach area are related to academic success and cognitive health.

For more information, view the abstract or contact the investigator. 

Exercise May Turn Off Bad Genes in Persons with Heart Failure

More than 6.5 million people in the United States are living with heart failure (HF). Scientists are looking for new targets for HF therapy that can help people lead better lives. One approach is finding how behavior can turn on and off genes, by changing the epigenetics. HF is an inflammatory disease, and higher inflammation leads to worse HF. In this pilot study, participants were randomly assigned either to a three-month walking exercise group (n=38) or a control group (n=16). The investigators found that exercise training was able to turn off an inflammatory gene in persons with HF. By turning off this gene, there was less overall inflammation. Changing the epigenetics, or the process of turning genes on and off, may be a natural way that exercise can lead to better outcomes in persons with heart failure.

For more information, view the abstract or contact the investigator.

Make Space for Testosterone? Supplements to Exercise May Help Astronauts Maintain Muscle Mass In The Future

Testosterone is a male hormone that is known to boost muscle growth in young men. It is often used to treat older men to help fight age-related muscle loss. Muscle loss is also a problem for astronauts during long missions in space. While astronauts exercise regularly to reduce muscle loss during space flight, this is not always enough. In this NASA study, healthy men, average age 35 years, were confined to head-down tilt bed rest for 70 days to mimic space flight-related effects on muscle. None of the 24 men who completed the study were allowed to get up during the 70 days.  Eight did no exercise (controls), while the other 16 followed a strict and specially designed routine of aerobic and resistance exercises. In addition, half of the exercise group received intermittent periods of testosterone treatment. The findings of the study showed that exercise reduced the losses of muscle size and strength and that the added testosterone treatment resulted in increased muscle size. Thus, while astronauts should continue to exercise to stay healthy, treatments like testosterone may be a safe supplement where exercise alone is not enough. 

For more information, view the abstract or contact the investigator.

A Hard Day’s Work May Reduce Older Workers’ Ability to Keep Cool

Workers in many occupations often perform back-to-back days of hard work in hot conditions. This can cause excessive fatigue and sweating, as well as dangerous increases in the body’s internal (core) temperature over the workday. This increases the risk of heat-illness. In this study, investigators at the University of Ottawa were concerned that, for older workers, a hard day’s work in the heat might also affect their ability to keep cool on the next workday. Using a direct calorimeter, a unique device that precisely measures how much heat the body can dissipate, the study team assessed nine healthy, middle-aged men (53-64 years) during exercise in the heat on the same day prior to (day one), and on the day following (day two), a simulated workday in the heat. They found that a reduction in the body’s ability to lose heat on day two (compared to day one) – this led to a greater amount of heat being stored in the body and a higher body core temperature on day two. These findings indicate that a hard day’s work in the heat reduces the body’s ability to keep cool and may elevate the risk of heat-illness in older workers on the next workday.

For more information, view the abstract or contact the investigator.

HIIT in the Real World: Does It Really Work?

High intensity interval training (HIIT) is popular because it is an effective way of gaining exercise benefits, while enabling that outcome with less time investment than regular exercise. However, it is not currently known whether overweight people will do HIIT on a long-term basis–without the intensive support that most research studies provide. In this study of 250 overweight adults, the investigators chose 104 people to try unsupervised HIIT–they did their exercise sessions three times each week, instead of doing regular daily moderate-intensity exercise. After one year, those who had opted for HIIT had not lost more weight or improved their fitness, in comparison to those who chose normal types of exercise. However, only 20 percent of the people who chose to try HIIT were still doing it regularly after one year. Members of this 20 percent HIIT-adherent subgroup were more likely to be men and were more likely to have lost significantly more weight and body fat than those who didn’t do HIIT regularly. This study shows that many people cannot maintain an independent HIIT program. However, if they do, they will lose fat and gain health benefits.

For more information, view the abstract or contact the investigator.