This set is a nice way to get some milage in without being boring. The main set has two rounds and is to be swam straight through. The set is based on 1:30 being the off time for 100m and other times are scalled off that, except for the 50s, they have an extra 5 seconds taken off to give it a bit of a kick. Two versions of the main set are provided, one Frontcrawl and one IM version.
The usual disclaimers apply, this is session is written for my own ability. I don’t mind if people adapt it for themselves or have a go, but they do so at their own risk.