My 8 yo child told me that they learned at school that they should lay down flat on the ground in case of lightning. I told him that the more correct position is crouching down with feet together, but it looks like that there is no better or worse position.
I then tried to find some information on the actual risk of lying down, but found none. I can imagine a worst case scenario where the lightning hits you close to your feet so that you are radially oriented towards the field change and that the potential difference between heart and feet would be enough to trigger a ~30+ mA current in your body (this is also the limit for AC current in home installations in Europe).
Assuming that you are not fried (and whatever is practical for the estimation), would the radial potential gradient big enough for a lethal current?