Once it succeeds, will legs, abdomen, back, buttocks, tense automatically and without effort of will. The first few minutes were disappointing: I did not plan to stand. After a pause, the next experiments. Towel etc. inferior: It then shakes a little less! At the beginning is essential. And after a few minutes I was shaky on the part. A few seconds. Bottom, back, automatically tense abdomen. More tough tests: After 10 minutes, safer state was possible. Then I played standing on the internet and I was a bit of sweat. Soon I could safely stand on the right leg. The left is still shaky. A great device for idlers who can do what and by the way want. My goal is, as far as to get into the balance that I can safely inline skating. I hope this is the right exercise for?