I'm one run away from graduation, one week short of a year since I started. I have a 5K race at the end of November, so as I cover about 3.6k in 30' I have decided to add a little bit to each run through November, until I can get to 5k (today was 3.78k in 30:51), and my breathing was hard and noisy towards the end. I have a one mile riverside route, which I am now doing two and a quarter times, and I know that to get to 5k that I need to do it three times.
I had a lot of trouble regulating my breathing at the start of the programme, and when C25Kers here ask how to regulate this I have no idea what to say because mine sort of fell into place with time and a good asthma medication regimen. So today I decided to be aware of how I was breathing. I start in through my nose, and out through my mouth, but it's only 200m until I need to also breath in through my mouth every third breath or so. I concentrate on pushing the out breath out, and the in breath then happens automatically. Towards the end of the run I was back to noisy out breathing, but I think this will quieten with improved fitness. I was also trying to sprint a bit in the last 60 seconds, sprint being a loose term in my case! My average pace in 8:10 (mins/km) and in the last minute I reached 5:18 for about 20m.
For any other London based runners this is the race <http://www.5kredrun.co.uk/> It's free to enter with a minimum fund raise of 50GBP and soup at the end.