You are probably in a good enough shape to benefit from HIIT. For usual couch potatoes it might not be the case; it would benefit them more to start with swimmi

You are probably in a good enough shape to benefit from HIIT. For usual couch potatoes it might not be the case; it would benefit them more to start with swimming/walking, then later running a bit and once they are somewhat in shape and have proper injury-avoiding practices, they can do HIIT.