@AmyBrockman said in Ability to create customized interval workouts:
This has probably been mentioned somewhere on this forum before, my apologies if it has, I would imagine it might be a common topic…
Yes it was, several times 
Please use the search function before opening a new thread.
I’m closing this one to avoid duplicates.
https://forum.suunto.com/search?term=Structured interval&in=posts&matchWords=all&sortBy=relevance&sortDirection=desc&showAs=posts
https://forum.suunto.com/search?term=Trainingpeaks planner&in=posts&matchWords=all&sortBy=relevance&sortDirection=desc&showAs=posts