The rate at which work is done or energy is transferred is power. To determine the power produced by a paddler, use the equation:
Since work is equal to force time distance,
Velocity is equal to the boat's distance traveled over time, thus:
WHICH MUSCLES DO YOU USE?
When kayaking, the muscles in the upper body are predominantly used. A stand up paddle board engages the same upper body muscles plus utilizes the core and leg muscles for stability.
Figure: The paddler on the left highlights the key muscles that are engaged when kayaking. This includes: lats, traps, biceps, triceps, and deltoids. The paddler on the right is SUPing. In addition to the upper body muscles used when kayaking, this paddler is also engaging their abdominal and leg muscles.
Maintaining the paddler's box allows a paddler to produce maximum power and prevents the risk of injuries and fatigue on the shoulder and arm muscles. The paddler's box refers to the rectangular shape that is formed between the paddler's hands in relation to the shoulders when the paddle is extended out in front of the paddler's chest. It is important for the paddler to rotate their torso to maintain this rectangle shape as best they can to reduce the risk of injuring shoulder and arm muscles.
Figure: The imaginary rectangular box (yellow dotted line) represents the paddlers box.
It is important to find the right balance between exerting maximum power and maintaining stamina. Engaging the entire body produces the most power, but causes a paddler to become fatigued more quickly.
Imagine there is a force arrow pointing from the blade of the paddle. To propel the boat forward, this arrow must be as close to the direction of motion as possible. Furthermore, the shaft should be as vertical as possible to not waste power pushing the boat into or pulling the boat out of the water.
Figure: Notice the force arrow coming off of the paddle blade as compared to the force arrow indicating the direction the boat is propelled. When the paddle shaft is tilted forward, it causes the boat to be pulled down, deeper into the water. Conversely, when the paddle shaft is tilted back, it causes the boat to be pushed up, out of the water.