Been doing one 'barefoot' (ie in aqua shoes which are now so worn they've got a hole in the sole - so I guess that's pretty close to barefoot!) run a week for a few months now, and all my other running is done with forefoot strike. I've found the transition from heel striking tough, and thought I was doing something wrong - even now I can't so more than 4 or 5 miles (on the roads) without risking a calf strain. However, I recently discovered I have osteoarthritis in my right ankle, giving it less flexibility. I guess my calf muscle has shortened over time.

When I'm on the fells I do find I still revert to heel striking on steep downhills - with anything more than a gentle decline I feel like I'm stretching out too much and puttuing the brakes on with each landing - I know I should be using shorter steps, but my legs don't move fast enough!