title: Role of leisure-time physical activity in nonalcoholic fatty liver disease: a population-based study.
abstract: Physical activity (PA) is commonly recommended for nonalchoholic fatty liver disease (NAFLD) patients. However, there is limited evidence on the independent role of PA in NAFLD. The aim of this study was to examine the association between PA and NAFLD. We conducted a cross-sectional study of a subsample (n = 375) of the Israeli National Health and Nutrition Survey. Exclusion criteria were any known etiology for liver disease. Participants underwent an abdominal ultrasound examination; biochemical tests, including leptin, adiponectin, and resistin; and the noninvasive biomarker SteatoTest and anthropometric evaluations. A semiquantitative food frequency questionnaire and a detailed PA questionnaire were administered. Three hundred forty-nine patients (52.7% men, 30.9% primary NAFLD) were included. The NAFLD group engaged in less aerobic, resistance, or other kinds of PA (P </= 0.03). The SteatoTest was significantly lower among subjects engaging in any PA or resistance PA at least once a week (P </= 0.01). PA at least once a week in all categories was associated with a reduced risk for abdominal obesity. Adjusting for sex, engaging in any kind of sports (odds ratio [OR] 0.66, 95% confidence interval [CI] 0.44-0.96 per 1 standard deviation increment in PA score) and resistance exercise (OR 0.61, 95% CI 0.38-0.85) were inversely associated with NAFLD. These associations remained unchanged after adjusting for homeostasis model assessment, most nutritional factors, adiponectin, and resistin. Only the association with resistance PA remained significant with further adjustment for body mass index (OR 0.61, 95% CI 0.44-0.85). Adding leptin or waist circumference to the model eliminated the statistical significance.
  
  
  CONCLUSIONS
  Habitual leisure-time PA, especially anaerobic, may play a protective role in NAFLD. This association appears to be mediated by a reduced rate of abdominal obesity.
authors.affiliation: The Liver Unit, Department of Gastroenterology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
authors.forename: Shira
authors.initials: S
authors.lastname: Zelber-Sagi
authors.forename: Dorit
authors.initials: D
authors.lastname: Nitzan-Kaluski
authors.forename: Rebecca
authors.initials: R
authors.lastname: Goldsmith
authors.forename: Muriel
authors.initials: M
authors.lastname: Webb
authors.forename: Izabel
authors.initials: I
authors.lastname: Zvibel
authors.forename: Ilana
authors.initials: I
authors.lastname: Goldiner
authors.forename: Laurie
authors.initials: L
authors.lastname: Blendis
authors.forename: Zamir
authors.initials: Z
authors.lastname: Halpern
authors.forename: Ran
authors.initials: R
authors.lastname: Oren
mesh_terms: D052242:Adiponectin / Q000097:blood; D000328:Adult; D015992:Body Mass Index; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005234:Fatty Liver / Q000097:blood / Q000503:physiopathology* / Q000628:therapy*; D005260:Female; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D007557:Israel; D007899:Leisure Activities; D020738:Leptin / Q000097:blood; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009043:Motor Activity / Q000502:physiology*; D015999:Multivariate Analysis; D009752:Nutritional Status; D009765:Obesity / Q000097:blood / Q000503:physiopathology; D052243:Resistin / Q000097:blood
chemical_list: D052242:Adiponectin; D020738:Leptin; D052243:Resistin