Is it true that SS cardio is better if you are on a keto diet? And if so, should I do HIIT the day after my cheat meal? Thanks!
HIIT cardio runs off of stored glycogen, and as such, if you are on a keto diet, doing excessive amounts of it may lead to more muscle loss than you find acceptable. If you're having one cheat meal, or refeed day etc, you may not want to dig into your newly stored glycogen so quickly. Steady state is the safer call in your case as you're not just after weight loss, but fat loss with muscle retention.
Cardio is vastly overrated. You aren't going to run off a bad diet into single digit body fat.
Walking is for digestion, bf level is mostly about diet, lifting is for muscle.