Why can't I run as fast as I walk?

[sniffle12]

I've always been a fit and fast walker but have never been able to run.

I've started a running challenge and am finding it really difficult, but the silly thing is I can speed walk at 7kph on the treadmill until the cows come home, but if I then switch to a run at 7kph I just can't keep it up, even though it's the exact same speed!

As I'm new to running I'm just trying to understand the mechanics of it. Clearly it's not a speed thing - so what is it about running that's so much harder than just walking fast?

Running is inefficient compared to walking that is to say it requires more effort because you are taking off and landing, when you say you cant keep it up do you mean that you get out of breath?

Not really out of breath but I just feel exhausted, hot, sweaty, like I can't keep up - it just becomes hard to concentrate for how uncomfortable I feel. Whereas speed walking I feel cooler and more in control even if the speed is the same.

I find running tough too, but I cant walk as fast as you!
how about you try a minute running and a minute walking, sorta c25k type protocol then gradually build up to less time walking & more time running

What about doing C25K , that way you can build up how much you run over time.

From experience, the first few minutes of any running session can feel hard - it does take a while for the body to acclimatise. I would forget any comparisons with your walking speed and settle for a speed that feels comfortable for you to run. It doesn't matter if this is slower than your walking pace. You can work on speed later, once you've built up frequency and duration. It might be easier to run outside at first and just get comfortable with the process of running. It really does become easier with practice.