No two swim workouts should be the same! We all have different skills, goals and training abilities so it’s super important to make sure our swim workouts are personalized to our speed to help us meet our goals.
The intervals are a function of the number of reps, distance, stroke type, eneergy zone, and your threshold ability for that particular stroke. An elite swimmer may be able to do 10 x 100s Freestyle @ 1:10, while a more beginner swimmer may do that same set of 10 x 100s Freestyle @ 2:00.