I'm really searching for a useful advice. I work as copywriter in office and I spend really much time sitting while I'm writing articles. And because of that I feel usually very tired of beign too long in one and the same position. Also back pain after the working day is really awful, it's so bad now and what will happen when I'm pregnant again (we're planning to have a second child during next year)? Are there any solutions for this? What can you recommend me?