Evaluation of Paddling Performances through Force Acquisitions with a Specially Instrumented Kayak

Kayaking is an athletic discipline admitted by the International Canoe Federation (ICF). In flat-water racing events, paddlers race on a straight course, each boat in a separate lane, over different distances up to 1000 m. There are kayak events, for men and women, in single (K1), double (K2) and four paddlers (K4). This form of racing is an Olympic discipline and its programme includes events over the distance of 500 m and 1000 m. Unlike canoeing, where the paddler is kneeling on one knee, and uses a single blade paddle, the kayak athlete is seated and uses a two-blade paddle. Both kayaking and canoeing are sports whereby propulsion of the boat is derived mainly from muscle actions of the upper body. This paper presents the evaluation of paddling athletic performances during K1 training session by means of an instrumented kayak with a stand-alone data acquisition system. The on purpose experimental device is first presented. Force strokes measured through instrumented paddle with strain gauges at both ends are simultaneously recorded with the hull speed of the boat. A deep analysis of the different phases of the stroke sequence (i.e. 1-preparation and catch phase, 2-propulsion power or stroke, 3-stroke end 4-exit phase and aerial preparation of the next stroke) is available for each training session of the athlete. Effect of stroke rate on average velocity and on the application and exertion of force during the drive phase of the stroke cycle is analyzed. In this way some important considerations can be related to paddling parameters such as the angular offset of the blades, the grip width and the angle of attack which is the angle at which the blade enters the water. Quantitative measurements of paddle forces during on-water training offer a particularly suitable system to evaluate the techniques of paddling and racing sprint boats and to refine the efficiency of stroke and paddling style.