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This week: Sleep lost and weight gained • Cardio versus weights effect on metabolism • Fitness Show & FILEX Immersive this October

Sleep lost and weight gained…

new study from Sweden has added to previous study findings that, in addition to other negative health impacts, lack of sleep can lead to weight gain.

Researchers from the University of Uppsala found that one night of sleep loss has a tissue-specific impact on the regulation of gene expression and metabolism in humans.  This may explain how shift work and chronic sleep loss impairs our metabolism and adversely affects our body composition.

In the new study, the researchers studied 15 healthy normal-weight individuals who participated in two in-lab sessions in which activity and meal patterns were highly standardised. In randomised order, the participants slept a normal night of sleep (over eight hours) during one session, and were instead kept awake the entire night during the other session. The morning after each night-time intervention, small tissue samples (biopsies) were taken from the participants’ subcutaneous fat and skeletal muscle. These two tissues often exhibit disrupted metabolism in conditions such as obesity and diabetes. At the same time in the morning, blood samples were also taken to enable a comparison across tissue compartments of a number of metabolites. These metabolites comprise sugar molecules, as well as different fatty and amino acids.

The tissue samples were used for multiple molecular analyses, which first of all revealed that the sleep loss condition resulted in a tissue-specific change in DNA methylation, one form of mechanism that regulates gene expression. DNA methylation is a so-called epigenetic modification that is involved in regulating how the genes of each cell in the body are turned on or off, and is impacted by both hereditary as well as environmental factors, such as physical exercise.

‘Our research group were the first to demonstrate that acute sleep loss in and of itself results in epigenetic changes in the so-called clock genes that within each tissue regulate its circadian rhythm. Our new findings indicate that sleep loss causes tissue-specific changes to the degree of DNA methylation in genes spread throughout the human genome. Our parallel analysis of both muscle and adipose tissue further enabled us to reveal that DNA methylation is not regulated similarly in these tissues in response to acute sleep loss’ said Jonathan Cedernaes who led the study.

Source: University of Uppsala

Cardio versus weights effect on metabolism

Researchers from the University of Copenhagen have come closer to understanding the diverse effects of different forms of training. In a new study published in the scientific Journal of Clinical Investigation –  Insight, the researchers show that cardio training on an exercise bike causes three times as large an increase in the production of the hormone FGF21 than strength training with weights. FGF21 has a lot of positive effects on metabolism.

‘Of course it is very exciting for us researchers to see how different forms of physical activity actually affect the body differently. We have known about the effects of various forms of training on more well-known hormones like adrenalin and insulin for a long time, but the fact that strength training and cardio exercise affect FGF hormones differently is new to us’, says Associate Professor from the Novo Nordisk Foundation Center for Basic Metabolic Research Christoffer Clemmensen, who is one of the researchers behind the study.

The researchers have studied the effects on 10 healthy young men, who had been randomly divided into two groups and did both forms of training once a week. Both training forms were relatively hard and lasted 60 minutes. The cardio exercise consisted of cycling at a level of 70 percent maximum oxygen intake, while the strength training consisted of five exercises repeated 5 x 10 times and involving the main muscle groups in the body.

Subsequently, eight blood samples were taken from the participants over a period of four hours in order to measure the development in blood sugar, lactic acid, various hormones and bile acid in the body. It was these measurements that revealed a significant increase in the production of the hormone FGF21 in connection with cardio exercise, while strength training showed no significant change with regard to this hormone.

Source: University of Copenhagen

Fitness Show & FILEX Immersive this October

If you’re looking for a little industry inspiration you can catch the 2018 Fitness Show in Melbourne on 13 and 14 October.

The Show brings together the latest in fitness education, technology, health foods, sports nutrition, group fitness and fitness apparel. For fitness professionals, the event provides a platform to meet face-to-face with fitness and health business owners and expand your professional network.

As a fitness professional, you can register for a complimentary two-day access pass to attend the Fitness Show Melbourne by using the code IND at

The Fitness Show is open to trade and general public from 10am – 5pm on both days at the Melbourne Convention & Exhibition Centre, Southbank.

The Fitness Show is co-located with the FILEX Immersive event, which features 13 sessions over two days, addressing industry topics pertaining to business and fat loss. You can find out more and register at

Source: The Fitness Show

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