QUOTE (Ironkid94 @ Mar 8 2009, 08:11 PM)

Funrunner,
are you saying if I pack on muscle it could slow my running down..?
Currently, I'm 64.2kg and 165cm.
Cheers,
Chris
What I'm saying Chris is your current weight and height gives you a Body Mass Index of 23.6. In adults, a range of 20-25 is considered "healthy". Above that is considered either overweight or in extreme cases, obese.
Putting on an extra 5-10kg won't add to your height, so you'll end up with a higher Body Mass Index- nothing necessarily wrong with that if it's in the form of muscle and your skeleton can hold it. Arnold Schwarzneger, Gordon Tallis, Alan Langer are all examples of guys with high Body Mass Indexes that performed really well in their chosen sports.
However, in running, generally speaking, it's really the sprinters who have well muscled upper bodies, whereas endurance athletes tend to have leaner bodies.
You just need to decide what you want to do. Generally speaking carrying more weight in the upper body won't help you run faster over longer distances, it just increases the amount of work you have to do over those longer distances.
You might want to think about strengthening your "core" with Pilates type exercises.
Be interesting to see if someone shoots me down on what I've just said- they're my ideas,
Funrunner aka Craig