Standing up straight

amerr

I started the 30 day shred 11 days ago and ever since about day 5 I have noticed that I stand and sit up straighter than I used to and I find myself tightening my abs at the same time. My mom would be so proud. She's spent her entire life telling me to stand up straight and Jillian seems to be getting my core strong enough to do it! Anyone else notice anything like this after beginning to exercise?