Why ask me how long I have to workout each time?
From what I understand, Intelliburn is an algorithm that determines which videos to display for you based your answers to the questionaire and how you rate each video you watch. I imagine there is some weighting done to each variable in order to bias certain things. Which is to say, it likely biases selection towards workout type rather than time. So it selects videos of a variety that firstly). you are interested in, secondly). that it thinks will help with your goals, and finally). that fit in your timeframe. As buckry said, there aren't a lot of videos at the 15-30 minute range that are really good for most goals so you will tend to get longer videos. Just remember that you can always rate a video as too long after you've completed it to better help Intelliburn understand what it is you're looking for.
I noticed this as well, the videos in the 15-30 minute category aren't really strong workouts on their own. I started out trying to do 30 minutes and eventually just freed up more time, usually I do a full hour now, 2 30's or a 40 and a 20. There just aren't any great short workouts here, however that being said, doing an hour has been amazingly effective, I've lost 8 pounds in a month. I doubt I could have done that with only 30 minutes.
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