A side ache will inevitably haunt one of your runs, they key is to not let it ruin your workout. When a side ache arrises address it immediately:
1. Slow down but DO NOT stop
2. Lift your arms above your head (I place the palm of my hands on the back of my head, kind of like you do when you do a sit up).
3. Stop talking and focus on your breathing, try to exhale very deeply.