Inclusion Criteria:  Age 18-69 years Sedentary [<90 min/wk of exercise identified by the Get Active Questionnaire (GAQ) BMI >30kg/m2  Liver biopsy within six months prior to enrollment showing:  NASH defined by NASH Clinical Research Network (CRN) histology scoring system (NAS) >4 and MRI-PDFF >5% and; Liver fibrosis stage 1-3  Exclusion Criteria:  Active cardiac symptoms Body mass index (BMI) >45kg/m2 Cancer that is active Inability to walk >2 blocks Institutionalized/prisoner Other liver disease Pregnancy Secondary hepatic steatosis Severe comorbidities AUDIT-C questionnaire identified significant alcohol use Substance abuse/active smoking Uncontrolled diabetes (changes in drug dosing over previous three months or A1c >9%) GAQ response indicates exercise may be unsafe.