Thanks so much for this educational video. I just wanted to make two points, instead of the Apple body shape which describes a person with a big shoulder. You probably meant Pear shape, meaning a person's shape is round with a belly greater than the shoulder. The second one is about the HIIT resting time principle, during the demo section you said we should exercise for 30 seconds and rest for 10 seconds before resuming the exercise. As I know the HIIT resting intervals are usually equal to or longer than the exercise time depending on how intensive the exercise is. In order to reach the VO2 index the formula is HR = 220 - person's age.