Change your shoes every (500km or so) say the manufacturers. If you run on roads and still heel strike, then maybe the advice is not as self-seeking as it seems to a sceptic like me. Since I started running mid-foot (simply by pushing both nipples forward by 1 cm) it seems the shoe has become less important as the foot – designed by mother nature expressly for the job – does more of the work.
Finally one morning the shoes gave up the ghost.

Time for new shoes?
Time for new shoes? No need. In Nepal you can find someone on many a street corner to fix them up. They’re equipped with industrial needle, strong thread and a brain-numbing glue. Rs. 20 later (just €0.20) and the shoes are almost as good as new. Almost.

Gopal (Kumari) fixing shoes on Lazimpat