I've been training for a marathon and recently, when I started training with a group, I put more pressure on my body. I ran more times a week (from three days a week to like five or six.) I've also been adding more mileage slowly but surely in accordance with a training plan. While my body has been adapting to the mileage without problems, not so much with my mileage pace. When I started running with the group, I could pull off a seven and a half minute pace for six miles. My muscles were loose and flexible. I could have probably ran that way for at least 10 miles. Now as I get more involved with this group, and adhere more to disciplined runs on an almost daily basis, it seems like I just don't feel as powerful. I go out, and feel soreness in my soleus and calves, and just don't have the "spring" that I had before. Also my pacing has dropped to where, my leg muscles, while ripped more than they ever had been, just get way too tight during runs for me to keep up the pace I had before. Can someone give me some insight and suggestions?