Hi Cecilia Tilley. Great question. In a previous version of Grokker, if you followed an expert, you would receive a notification whenever the expert commented on something. However, that resulted in users receiving a lot of unnecessary messages, so we disabled that feature. We still offer the ability to follow an expert, so that in later versions we can add functionality around a user's expert preference. If there is anything you'd like to see related to following experts, please feel free to let us know. We'd love to hear some input.

In regard to advanced series...have you tried: Sarah Kusch's Interval Training/HIIT Program - https://grokker.com/fitness/interval-training-hiit/program/hiit-afterburn/58dd7fb42629dd1eb2e772c0. Or her Mind, Body Fit Program - https://grokker.com/fitness/interval-training-hiit/program/mind-body-fit-with-sarah-kusch/56cdd08cbd2d55dd2ff89f41. Or perhaps Kelly Lee's HIIT Club: https://grokker.com/fitness/interval-training-hiit/program/hiit-club-workouts-with-kelly-lee/5501c488d55df4db0c7459cc. You may want to go to the programs page and see if there are any others that fit your needs: https://grokker.com/recent_videos