"shock" to me is just simply changing your daily routine, I used to bike for 30-45 mins, after 21 days your body will get used to it and you will achieve less results, then I switched to power walking for 30-45 mins, then running, then the "ski" machine thingy for an hour. Also I mixed up the wights like from machines to free wieghts just making sure my body doesn't get used to it. As far as my goal wieght it was 160 which I achieved and I'm only 5'7 and I thought that weight would be fine for me.
Also I edited my original post (added more) take a look it might help