Advice urgently required!!!! I've been running for about 3 months, going from nothing to 5km! All my training is in the gym, and I quite comfortably run 5km in about 32mins - however, when I venture outside (I'm running the Race for Life June 1st), I can't run more than 0.5 mile without ending up massively out of breath and needing to stop. I smoked for many years (gave up 2 years ago) and suffer mild asthma - but don't understand why outside is so different from the gym. Any ideas how I can improve my outdoor running???