Tanita scales can be as much as 8% out (too high), and you could get your body fat down to 20% and still be the same weight you are now.
If you look at the stats I posted the other day you'll see I am heavier now than I was when the first test was done last year, but my body fat is lower. My hydrated body (amount of fluid, not just water) is also better, and water weighs too so the way I look at it is what is the fat, muscle and hydration like because if the muscle and fluid is good, then it doesn't matter so much about the weight.
I think of fat as being like a lazy oik having a piggyback - every moment of every day. It does nothing to contribute to the journey, whereas the muscle will be helping you every step of the way.
Of course, weight loss is always advanatgeous, especially if you want to run faster, but whilst you are doing that, sometimes looking at the other stuff helps if you are not losing weight - you may be losing fat and gaining muscle.
