Yeah I started to fast after a break, I was doing good with no shin splints, then took a week off and started with hill sprints and got them. I just need to be carefulAlso, for shin splints, you may need to lower your intensity and mileage to let your legs get used to running, your bones, tendons and ligaments take about 6-8 weeks from beginner status to adapt to running. If you do too much too soon it’ll lead to injury and shin splints.