A common paddling injury is blisters, if we grip onto the paddle too tightly it will cause blisters as there is a lot of friction between our skin and the fibreglass of the paddle.
When we increase our training volume or the amount of duration, we will increase the wear and tear on our hands. We need to increase our training volume over a longer period of time, not go from a small volume of training to a large volume of training in a short period of time.