DEFINING LOWER EXTREMITY DOMINANCE: THE RELATIONSHIP BETWEEN PREFERRED LOWER EXTREMITY AND TWO FUNCTIONAL TASKS

Abstract

Background: A commonly utilized operational definition of lower extremity (LE) dominance assumes the LE with which a participant prefers to kick a ball with is the same preferred LE a participant would choose for a unilateral landing task. Hypothesis/Purpose: The purpose of this study was to determine the relationship between the preferred lower extremity (LE) when performing a unilateral landing and kicking task. The authors hypothesized a strong correlation between the LE the participant chose for the landing task and the LE the participant chose for the kicking task would be evident. Study Design: Repeated measures. Methods: A convenience sample of 50 (age = 21.9±0.9 years; sex = 27 female; 23 male; height = 170.6±10.8 cm; weight = 73.3±18.3 kg) healthy, recreationally active college aged students performed two tasks (kicking a ball; unilateral drop jump landing) in a counterbalanced order. Results: Thirty-three participants kicked and landed with their right LE; 14 kicked with the right and landed on their left; two kicked and landed with their left and one participant kicked with their left and landed on their right LE. The Phi Coef-ficient (φ = 0.18; p = 0.18) indicated little to no relationship between the preferred LE for kicking a ball and landing from a drop jump. Similarly, the Chi-squared statistic revealed no differences between observed and expected frequencies (χ2 = 1.76; p = 0.23). Discussion: When studying anterior cruciate ligament injury mechanisms in the laboratory, most investigators examine characteristics of the dominant LE. Dominance is frequently defined by which LE the individual kicks a ball with. The majority of ACL injuries however occur to the landing or plant LE. Hence, LE limb selection based on this approach may be flawed. Conclusion: A significant relationship was not evident between the preferred LE for kicking a ball and a unilateral landing in a group of healthy recreationally active college aged students. The data suggests the preferred LE for kicking a ball and a unilateral landing task is not necessarily the same.