Evidence from animal models and clinical data suggest that maternal obesity programs a range of detrimental effects in offspring, and limiting gestational weight gain may be a useful strategy to reduce these. Therefore we investigated the impact of voluntary exercise during pregnancy on markers of metabolic disease in adult offspring of obese and lean mothers. We used female Sprague-Dawley rats that were fed chow (C n=28) or high fat (F n=32) diet for 6 weeks before mating. Ten days before mating, half of each group were offered voluntary exercise with a running wheel (CE or FE), while the others remained sedentary (CS or FS). Wheels remained in home cages until the end of pregnancy. Pup body weight (BW) was monitored and two pups from each mother were killed at postnatal day (PND) 19. Thereafter siblings were fed chow and killed at 13 weeks for metabolic assessment. Both lean and obese mothers had similar modest levels of exercise (8.1±2.4 vs 5.1±1.5 km), with no significant effect on maternal BW. At PND 1, lean exercised mothers had lighter male and female pups (P<0.01), with no effect in those from obese mothers. Maternal obesity increased offspring BW and adiposity at PND 19 and 13 weeks with no effect of maternal exercise. Adult male pups from obese mothers had higher plasma insulin, leptin and triglyceride concentrations, which were normalised by maternal exercise, while in females only the insulin concentration was raised. In the males, hippocampus mRNA expression of TLR-4, FTO and IL-1β were upregulated by maternal obesity, and normalised by exercise (P<0.05). Thus, maternal obesity increased the risk of metabolic disease in adult offspring, with higher BW, adiposity, hyperleptinemia, hyperinsulinemia and increased brain inflammatory markers and FTO. Interestingly maternal exercise had sex specific benefits which were more marked in male offspring.