Having all these paddling pictures on here you would think that I spent most of my time on the water, but I'm starting to ramp it up a bit with my running .My training , I guess I shouldn't  call it training because there is no consistency in my running I don't believe in doing long runs like running an marathon distance every other day. I find that running a more strenuous shorter route say 10 or 12km . :instead of running 20 km on the road"-- is just as beneficial  our breaking up your long run of 24 km in one day instead do a  12 km one day and the other 12 km the next day. But total distance is different for every one  some people think 20 km is long but then if your training for a marathon you should at least be able to run 30 km comfortable. I found that when I trained for a half marathon I rarely ran that distance, But was able to do the longer runs because with my training I did a lot of shorter hillier runs.