I was wondering if I could do Hiit workouts or other basic cardio workouts, burpees etc. on these tiles.

Using the 1/2" Eco Soft + tiles is not recommended for HIIT workouts because they can separate under repeated aggressive movement. We would recommend you check out some of our rubber mat products that are better suited for HIIT style workouts. If you do choose to use the 1/2" Eco Soft + tiles for exercise it is recommended that you use a double sided tape on the underside of the tiles to secure them in place.