See how long you can hold your breath underwater.

“When I began my own attempt, I was already shivering like mad. I was able to hold for one-and-a-half minutes underwater, but it wasn't anything like it was on land. Put me on a yoga mat, and I can relax the rest of my body, but in the water, shivering and watching, it's incredibly difficult. It didn't occur to me until I returned from the event that I hadn't been swimming with my head underwater since I had a near-death experience during two surgeries. This is a primal fear I didn't have before, that sort of kicked in when I had to let go and float without breathing.”

“My swimming pond is 7 metres long and can only safely be entered and climbed out of at one end. Although I can pause holding on to a strap at the far end, whenever I swim I am committed to at least 14 metres. I can’t breath while doing so, the water being wild, is murky with lots of bits and bobs in it, not to mention the animals, so the traditional half submerged side breathing with a front crawl is not an option. So what I do is simply hold my breath and take a couple at each end when turning, obviously this is only possible for a while before a break out of the water has to be taken or a longish hanging on at one end or the other.”