Anecdata: shin splints injuries are usually bad biomechanics and easy to solve given interest on the topic. After many years without any running at all, it took me 6 months from 0km to running 5 half-marathons (1 every 15 days at the end of such period) without injuries. I was 35 when I started, I think. I enjoy barefoot techniques quite a lot, but I recommend caution.