In our Framingham Offspring Study, in a community setting, our findings were threefold: firstly, in persons with DM, we observed that greater physical activity was associated with higher circulating IGF-1 and BDNF levels; secondly, the association with IGF-1 was only significant in older adults (≥60 years) with DM; and finally, no significant relations were observed in adults without DM. This evidence concerns the gene IGF1 and diabetes mellitus.