I just started track this year and I'm doing sprints. I've been ok for the first 2-3 practices but after that, my quads hurt a lot after I sprint really hard. It goes away for the day if I stop running but if I start running again, it hurts even more. I've never had soreness like this before, even when i was doing weight training and I was wondering if it is a problem. It feels like my quads are really bruised and whenever I run or walk, it feels like someone is punching it really hard. It also feels like they are going to tear if I run again. Ive been stretching a lot but it doesn't seem to do much. Any advice?! thanks