Diabetes is related to retinopathy. Therefore extreme care should be taken when doing certain types of exercise. In particular, caution should be exhibitied when undertaking:
- Jumping. (Reference)
just trying to get multiple references going. 
so that when i re-use it works like this
- Gleeson and Bishop (2013). dfhtghnekd g wterp erger. 12-13.
- this is a new one.