Paddling may not be for everyone, but its a big component of the popular multis-sport races favored by Australia and New Zealand, adventure racing, and for some, an endurance pursuit in its own right. For these reasons, it it included in the guide. If you have neither the inclination to add paddling to your training, or the equipment for it, feel free to use similar rowing or swimning workouts instead.
But for those that are keen--you probably love a day on the water as much as I do. Although my paddle workouts are among the lowest intensity of my efforts, I still consider them valuable. It's not that I'm slacking off when I'm in a boat, it is more the fact that there is little opportunity (in my normal paddling circumstances) for objective feedback and quite often there are environmental conditions to contend with as well. There may also be the issue of not really incorporating much of your lower body into the action.
Now what I said for swimming goes doubly for paddling, where technique is even more important. There is a HUGE difference between the speed and efficiency of a paddler with good technique and one without it, so do yourself a favor if you're just getting in to paddling and either get someone with experience to evaluate your stroke or watch heaps of online videos and refine it the DIY way. Whatever you do, make sure you've got good technique before you get too worried about adding the intensity with the workouts below. Note--these workouts can be done in just about any type of boat, from canoes to kayaks to packrafts, even stand up paddleboards!
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