In the News: Women Are Naturally Fitter Than Men, Mammograms May Not Be Useful, Exercise Can Make Body Fat Healthier

Women are naturally fitter than men. A new study published in the journal Applied Physiology, Nutrition and Metabolism looked at the natural fitness ability of women as compared to men. Researchers from the University of Waterloo directed women and men who were of a similar age and BMI to walk at gradually increasing speeds and inclines on a treadmill, going until they had reached 80% of their maximum heart rate. Each person wore a face mask to measure how much oxygen they used and how much carbon dioxide they produced.The results found that women adjusted to the exercise after about 30 seconds, while men took 42 seconds. Women had a 30% faster rate of processing oxygen overall, a clear advantage when it comes to physical efficiency. It’s important to remember that fitness can’t just be defined by aerobic power; how quickly a person adapts to an exercise level is really a good indicator of health and fitness. Inspired to start working out? Try these exercises. (T)

Mammograms may not be useful. Picking up early signs of disease is the best way to prevent cancer from spreading, so it is widely recommended by doctors that patients get screened for all types of cancer on a regular basis. However, a new study published in BMJ shows that mammography did little to reduce either deaths or advanced breast cancer over a period of 23 years in the Netherlands. The study involved all Dutch women who were screened with mammograms every other year between 1989 and 2012, a total of eight million women overall. Over a long period of time, there was no significant decrease in stage 2 to stage 4 breast cancers, and the mammograms designed to pick up tumors led to overdiagnosis (most of which not requiring treatment) 60% of the time. This is dangerous, as overdiagnosis of breast cancer can lead to additional biopsies and even treatments that expose women to side effects, without necessarily protecting them from cancer. To learn more about breast health, take this quiz. (T)

Exercise may create healthier fat. A new study, which was published last month in the Journal of Applied Physiology, found that just a single session of exercise may change the molecular workings of fat tissue in ways that, over time, could improve metabolic health. Researchers gathered men and women who were overweight but did not have insulin resistance, then tested their body compositions and took fat samples. The researchers then had each volunteer exercise on a treadmill or stationary bike for an hour at a moderately tiring pace, and an hour later, repeated the fat biopsies. In almost all of the volunteers, the fat tissue after exercise showed greater amounts of a protein that is known to contribute to the development of more blood vessels. More blood vessels in tissue leaders to greater blood flow, which is great for metabolic health. While the changes were not enormous, they were shown to occur consistently and after a single session of exercise. With continued exercise, one could expect to improve fat health over time. (NYT)