You'll notice several checkboxes around the training schedule. Click any of these depending on what you're looking to copy, cut, paste, delete.
In the example above we've selected day 26 Mon, 28 Wed and 29 Thu. In the bottom we've pressed copy.
We've then hovered over another day. We've given you two options regards pasting:
Paste
Paste keeping the structure
The 'paste' option will paste all the copied/cut parts into the same day, and keeping the structure will remember the day order you copied/cut them from and paste them keeping that logic.
PASTE
FITR