This is the second time I have attempted c25k and I have completed W4. However, I am doing it all at the gym on the treadmill. Today I read posts on here about running on the treadmill vs outside and the general consensus was it is better to run outside as it is more challenging. So now I feel a fraud for running on the treadmill and feel that I haven't actually achieved as much as I should, or indeed could, have. I appreciate that regardless I am in a better position now than I was 4 weeks ago, but still feel I am not really doing this 'properly'.
Anyone in a similar position or can offer any advice?