Martin, as a running/triathlon/endurance coach, you are not alone in dealing with the first few minutes of running.

Everyone can give you some advice on warming up or whatever and I think everyone can come up for what works best for them but the best advice I can give you is not a physical adaptation but a mental one....

NEVER JUDGE A RUN BY THE FIRST TEN MINUTES.

Running can be very hard on the body for the first few minutes until it reaches a point of bio-mechanical fluidity and internal adaptation. Add to this daily stress that affects you mentally.

As long as your not blasting the beginning of your run into an anaerobic zone, as you've already seen once you get past the first ten minutes your good.