I wouldn't consider myself particularly "fit" or "unfit", but I'm having problems running. I can run for about 1min30sec, and after that I just seem totally out of breath or in pain. I've had a history of foot-ailments in the past (knee muscles used to just 'give away', was resolved with insoles when I was young), but I'm still flat footed (and due to see a foot-person for insoles again). Loads of studies have shown that flat-footedness doesn't affect a persons ability to run (or their susceptibility to injury), but I'm unconvinced. I try, and try, but I just can't run any further. Even if I take it in run 1/walk 1 intervals, after the 4th running minute, my Soleus (muscle on the back of the lower leg) hurts too much to continue running. I do a 5 minute warmup walk before the run, and stretch properly after the walk, before the run. I don't think it's just a case of being unfit or unmotivated to push through, I'm just not physically ABLE to. It's probably worth noting that I run on tarmac. I was just wondering if anyone has got any tips or suggestions on how I could progress? It's a hell of a long way getting from "0.25 mile in 1:40 and in agony" to "1.5 mile in 10dd" -- but I've got lots of time to train to that level, if I can figure out how to make ANY form of progression. I've been stuck like this for about 5 weeks! Hopefully somebody with similar experiences will have some knowledge!