Your slow running and limited control is all in your head. If you have doubts that you won't be able to run properly, then most likely you won't. Remember your mind entirely, and its limitations for that matter, control/build/execute your dreams. It takes practice indeed, but 90% of dream control imo, is confidence and expecting things to happen. If you 100% know and believe that you will be able to run properly, then you will. Now sometimes it can be tricky, so I can suggest a few things that may work. Next time your in a LD and your running isn't right, look and see if your shoes are tied. Hard to run without properly tied laces. If you shoes are fine, try taking them off. Its possible that you have slow shoes on (in dreams objects can have abilities/characteristics that aren't possible in real life). Look around for some new shoes to put on or just try and run barefoot. You could also look around for a box of wheaties. Wheaties will definitely bring out the athlete in you! You may laugh at these suggestions, but you would be surprised how often things like this work. If you want to improve strength you can always take some steroids in the dream. Look around for a needle or some anabolics. If you ever are wanting an item/object in a dream. Just think about the object/picture it in your mind..and then look around for it. Much easier than spawning an object out of thin air. In dreams, there are always loopholes. The key is mastering these to exert control on your dreams. Some can control their dreams by pure will and brute force (lucky them), others have to find ways around it (like me). Be creative, because thats what LDs are all about! Good luck to you and I hope this helped.