April 8, 2015

Exercise Improves Non-Alcoholic Fatty Liver Disease

AMSTERDAM, the Netherlands -- April 8, 2015 -- A study published in the Journal of Hepatology shows that exercise, regardless of frequency or intensity, benefits obese and overweight adults with non-alcoholic fatty liver disease (NAFLD).

There are no approved drug treatments for NAFLD, but lifestyle interventions such as diet, exercise, and the resulting weight loss have been shown to help improve NAFLD. In particular, these interventions can improve some features of non-alcoholic steatohepatitis (NASH).

Weight loss is the commonly recommended strategy for all obese and overweight patients with NAFLD. However, the exact role of the amount and the intensity of aerobic exercise that would be needed to reverse or improve NAFLD (or NASH) have not been systematically assessed.

In the current study, researchers examined the effect of various aerobic exercise regimens in improving liver and visceral fat in overweight and obese people who had sedentary lifestyles. A total of 48 patients were randomised into 4 groups: low-to-moderate intensity, high-volume aerobic exercise (LO:HI); high-intensity, low-volume aerobic exercise (HI:LO); low-to-moderate intensity, low-volume aerobic exercise (LO:LO); and placebo (PLA) for an 8-week period. Change in liver fat was assessed by magnetic resonance spectroscopy (MRS).

All 3 treatment groups, irrespective of the exercise regimen, showed improvement in liver fat of about 18% to 29% from the average baseline of 7.5%, compared with the placebo group in which liver fat increased by an average of 14%. The improvement was independent of weight loss.

There were no significant differences between the various aerobic exercise regimens in reducing liver fat over an 8-week period. However, the investigators conducted additional exploratory analyses and proposed that there was a trend towards greater reduction in liver fat and visceral fat in the 2 groups that utilised either high intensity with low volume (HI:LO) or low intensity with high volume (LO:HI) aerobic exercise.

“The results from our study show that all exercise doses, irrespective of volume or intensity, were efficacious in reducing liver fat and visceral fat by an amount that was clinically significant, in previously inactive, overweight, or obese adults compared with placebo,” said Nathan Johnson, PhD, University of Sydney, Sydney, Australia. “These changes were observed without clinically significant weight loss.”

In an accompanying editorial, Rohit Loomba, MD, University of California at San Diego, San Diego, California, and Helena Cortez-Pinto, MD, Hospital de Santa Maria, Lisbon, Portugal, observed that "”here is good quality evidence to support that regular exercise is beneficial in reducing the risk of NAFLD. In addition, both aerobic and resistance training regimens are equally effective in reducing liver fat in individuals with NAFLD even in the absence of weight loss.”

They suggest that duration of exercise and intensity of exercise are both important and one could perhaps personalise the exercise regimen based upon a participant's choice and still achieve similar results.

“There are, however, no data to support that exercise alone without weight loss can improve or reverse NASH,” they added. “There is preliminary evidence that vigorous exercise may be associated with a decreased risk of having NASH. The individual and joint effect of dose and intensity of exercise and their association with improvement in liver fat and other histologic features that are associated with NASH are key research priorities. In our expert opinion, a more stringent exercise-regimen than the US Department of Health and Human Services recommends, coupled with dietary interventions, may be needed to induce improvement in liver histologic features associated with NASH.”

SOURCE: Elsevier Health Sciences
Log in to post comments

Tell us what you think of DG News

Click to like Click to dislike