In open-water swimming, reduce your kick frequency to use it primarily as a tool for stabilization and body alignment, in order to conserve energy and avoid breathlessness.

noli's read

Research in swimming biomechanics and physiology fully validates this recommendation for conserving effort. In a foundational physiological study, researcher Ingvar Holmér (1974) established that the flutter kick consumes a disproportionate amount of oxygen relative to its low propulsive contribution, which accounts for only 10 to 15% in long-distance swimming. Furthermore, data from the biomechanical study by Hollander (1988) confirm that leg work is three to four times less energetically efficient than arm work. In a literature review published by Paola Zamparo (2020), it is emphasized that the essential function of the kick in distance freestyle is to stabilize the pelvis to reduce hydrodynamic drag. In practice, adopting a minimalist rhythm such as the two-beat kick (one kick per arm pull) allows for maintaining this body alignment without overworking the large thigh muscles. Reducing this frequency thus preserves cardiorespiratory endurance and optimizes overall swimming economy.

the sources

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