Hey @suckypaddler Ill add a few things!
Speed in a kayak doesn't come from power, it comes from technique. If after paddling for a couple of hours your arms are tired, there is something wrong with technique.
• Here is a video on Youtube that will show how to do the forward stroke
• Keep your hands relaxed. Blisters or calluses is an indicator you are holding the paddle too tightly.
• Sit up straight, and have 5 points of contact with your kayak - Feet, thighs, bottom in the seat.
Good luck, have fun!