Help near pilates?

When they tell you to tighten your stomach, what does this suggest? Also, sometimes when the instructer on the video is saying this should really be hurting, I don't have a feeling it at all. I surmise this may be because I'm not really sure how to tighten my stomach. Is this right?Help near pilates?
Pilate's is not an intense workout, your not sup post to get really sweaty or tired. When they voice tighten your stomach it means push your stomach to your spine, so your wager on does not get hurt during the exercise. Pilate's is great for toning and sculpt but you should do another cardio workout with it to speed up the results, and because Pilate's burn little calories. Good luck.
Tightenening the stomach ability to sort of exhale and allow the stomach to expand which makes it tighten.