The impact phase of drop punt kicking for maximal distance and accuracy

Impact is an important aspect of the kicking skill. This study examined foot and ball motion during impact and compared distance and accuracy punt kicks. Two-dimensional high-speed video (4000 Hz) captured data of the shank, foot and ball through impact of 11 elite performers kicking for maximal distance and towards a target 20 m in distance. Four phases were identified during impact, with an overall reduction in foot velocity of 5.0 m · s^-1 (± 1.1 m · s^-1) and increase in ball velocity of 22.7 m · s^-1 (± 2.3 m · s^-1) from the start to end of contact. Higher foot velocity was found in distance compared to accuracy kicks (22.1 ± 1.6 m · s^-1 vs. 17.7 ± 0.9 m · s^-1, P < 0.05), and was considered to produce the significant differences in all impact characteristics excluding foot-to-ball speed ratio. Ankle motion differed between the kicking tasks; distance kicks were characterised by greater rigidity compared to accuracy kicks evident by larger force (834 ± 107 N vs. 588 ± 64 N) and smaller change in ankle angle (2.2 ± 3.3° vs. 7.2 ± 6.4°). Greater rigidity was obtained by altering the position of the ankle at impact start; distance kicks were characterised by greater plantarflexion (130.1 ± 5.8° vs. 123.0 ± 7.9°, P < 0.05), indicating rigidity maybe actively controlled for specific tasks.