I saw [most of] an infomercial on this. I rarely watch them. Many fitness equipment infomercials are for gimmick products. You can exercise well on a mat. I have not bought these products, but, judging from the infomercial, they are excellent training DVDs. One must be fit to do the exercises and will only get more fit, all other factors like diet remaining the same or being enhanced. Many exercises involve interval training and plyometrics. If you are a beginner, get a physician's approval before you start. Do not forget to stretch before and after the exercises.
My new fitness book Pocket Guide to Fitness Edition II is out now!