Assembly is - you have to make sure that the parts really engage each other. Then there is a very stable tires. The training is very effective. Gradually the bruises to leave and I can confirm that the body is really used to it. I've been training for 10 days daily 20-minute tire and lost 2cm hip. I have a BMI of 20 and therefore that's a good performance. My hip is all my life been my problem area, though I do a lot of sports
