Mirrored from Sudopedia, the Free Sudoku Reference Guide
A loop is continuous when it fully complies with the rules defined for that loop. A continuous loop has alternating weak and strong links all the way round. Candidates can then be eliminated outside the loop, but within the unit of the links with weak inference.
The following image illustrates the concept:
This loop has 2 simple rules:
When we close the loop at node A, we can see that these rules are obeyed by the complete loop. Therefore, this is a continuous loop.