When choosing a kayak fishing paddle, finding the right length paddle is critically important.
If the paddle is too short, you’ll either bang your hands or the paddle shaft against the side of the kayak with each stroke. Or, you'll burn yourself out extending your upper-body enough to get the blade in the water.
If your paddle is too long, your kayak will zigzag in the water, wasting your energy and the efficiency of the kayak. Additionally, high-angle stokes (used when more power is needed) will be more cumbersome and it becomes more difficult to use your torso. Your torso is where the most power is in your upper body. So when you have a paddle that's too long, you're forced to use more arms, resulting in more fatigue.
It's not difficult to find information online about what length kayak paddle a person should use. The most “official” determination is based off of the individual's height and width of your kayak. Through this process most kayak anglers will find that 240cm or 250cm should do the trick. However, there are a few things that could change that.
If you're an athletic/active paddler, have an open water (ocean) fishing kayak, or a narrower kayak, it's best to size down 10cm to 230cm or 240cm. If you're a more relaxed angler, frequently use the high-seat option in your kayak, or over-load your kayak with gear, it's common to size up 10cm to 250cm or 260cm. If you're in a really wide kayak, like the Jackson Big Rig, just jump right into a 260cm paddle.
Check out more sizing information here: Kayak Paddle Sizing Guide. One of the benefits of the kayak paddle evolution is the introduction of adjustable length shafts. Many of the best paddles on the market will come with the ability to adjust the paddle length, allowing you to extend the paddle length 15cm and adjust the feathering angle.