I fell over once crossing a river up at Arthur's Pass, NZ with a heavy pack on. I fell straight forward and wound up with the water (full on glacier melt) kind of on my hands and knees with water running just under my chest. Fortunately, I had my boots on and was able to get back on my feet - before the days when I started carrying trekking poles - I could barely breathe it was so cold. One reason I won't wear anything that looks like flip flops.