Myocyte

Should You (or Should You Not) Be Working Out on an Empty Stomach?

As the amount of fitness information available is getting bigger, the chances of being exposed to bad advice are also growing, creating more fitness myths than ever. Yet, one of the most debatable myths that has been out there forever is the myth of working out on an empty stomach.

It has been a prevailing thought for decades that you shouldn’t eat or drink prior to working out, and it seems that only recently the public has started questioning its accuracy.

“Fasted” versus “Fed”

The common belief of the effectiveness of the “hungry workout” isn’t unsupported; actual research backs it up. The British Journal of Nutrition1 and the International Journal of Sports Nutrition and Exercise Metabolism both published studies that show data in favor of “fasted” as opposed to “fed” training when it comes to the percentage of fat lost per workout.2

Additionally, a study published in the European Journal of Applied Physiology shows that fasted training provides a better anabolic post workout response to weight training, meaning it provides a better environment for building lean mass.

Namely, the conclusions indicate that “prior fasting may stimulate the intramyocellular [stored fats] anabolic response to ingestion of a carbohydrate/protein/leucine mixture following a heavy resistance training session.”3

Moreover, by providing better absorption of the post workout meal nutrients, fasted training has the great potential to improve insulin sensitivity, and is, therefore, an important agent in the fat loss process.

As insulin sensitivity shows how easily fat and muscle cells in our body take in glucose, regulating insulin sensitivity helps lower the blood sugar levels, which is one of the most important factors in weigh loss. The Journal of Physiology published a study4 that shows significantly greater insulin sensitivity improvement for the fasted training group as opposed to fed training group.

Finally, fasted training proved beneficial to endurance performance. In a study5 published in the Journal of Strength and Conditional Research, ten professional cyclists maintained lean mass, lowered fat mass, and maintained performance.

Why fed training is better?

However, there is another side to the story that trumps the beliefs of efficacy of fasted workouts. As sports dietetics specialist Kelly Pritchett, Ph.D., R.D. explains, while the body’s response to a high-intensity fasted workout is to burn glycogen, the stored up carbohydrates, eventually, the body starts to adjust to the new system and starts storing fat from the next meal and burning…

New stem cell method produces millions of human brain and muscle cells in days

Scientists at the University of Cambridge and the Wellcome Trust Sanger Institute have created a new technique that simplifies the production of human brain and muscle cells – allowing millions of functional cells to be generated in just a few days.

Human pluripotent stem cells are ‘master cells’ that have the ability to develop into almost any type of tissue, including brain cells. They hold huge potential for studying human development and the impact of diseases, including cancer, Alzheimer’s, multiple sclerosis, and heart disease.

In a human, it takes nine to twelve months for a single brain cell to develop fully. It can take between three and 20 weeks using current methods to create human brain cells, including grey matter (neurons) and white matter (oligodendrocytes) from an induced pluripotent stem cell – that is, a stem cell generated by reprogramming a skin cell to its ‘master’ stage. However, these methods are complex and time-consuming, often producing a mixed population of cells.

Opti-OX

The new platform technology, OPTi-OX, optimises the way of switching on genes in human stem cells. Scientists applied OPTi-OX to the production of millions of nearly identical cells in a matter of days. In addition to the neurons, oligodendrocytes, and muscle cells the scientists created in the study, OPTi-OX holds the possibility of generating any cell type at unprecedented purities, in this short timeframe.

Producing neurons, oligodendrocytes and muscle cells

To produce the neurons, oligodendrocytes, and muscle cells, the team altered the DNA in…

Immune cells play surprising role in steady heartbeat

macrophages and heart cells
IT’S ELECTRIFYING Macrophages (green) “plug in” to heart cells (light purple and pink), providing an electrical boost that helps the heart cells contract and pump blood, a study in mice finds.

Immune system cells may help your heart keep the beat. These cells, called macrophages, usually protect the body from invading pathogens. But a new study published April 20 in Cell shows that in mice, the immune cells help electricity flow between muscle cells to keep the organ pumping.

Macrophages squeeze in between heart muscle cells, called cardiomyocytes. These muscle cells rhythmically contract in response to electrical signals, pumping blood through the heart. By “plugging in” to the cardiomyocytes, macrophages help the heart cells receive the signals and stay on beat.

Researchers have known for a couple of years that macrophages live in healthy heart tissue. But their specific functions “were still very much a mystery,” says Edward Thorp, an immunologist at Northwestern University’s Feinberg School of Medicine in Chicago. He calls the study’s conclusion that macrophages electrically couple with cardiomyocytes “paradigm shifting.” It highlights “the functional diversity and physiologic importance of macrophages, beyond their role in host defense,” Thorp says.

Matthias Nahrendorf, a cell biologist at Harvard Medical School, stumbled onto this electrifying find by accident.

Curious about how macrophages impact the heart, he tried to perform a cardiac MRI on a mouse genetically engineered to not have the immune cells. But the rodent’s heartbeat was too slow and irregular to…