A high center of gravity horizontal velocity, the hole-entry technique, and an arched-back posture after takeoff are reported as important factors that contribute to improving backstroke swimming start. A recent study reported that starting performance can be improved with the modified archedback posture and high hip joints. We hypothesized that a starting technique involving the greater trochanter at a higher position could improve performance. The purpose of this study was to investigate the usefulness of the original starting technique by comparing it with the conventional starting technique using a backstroke ledge. The participant of the study was an international-level female college swimmer (height: 1.59 m, weight: 51 kg, FINA points: 893 points). Two 15-m backstroke-swimming tests were performed: a SEIKO backstroke starting system placed 4 cm above the water level (High) and our original starting technique (Original). The tests were filmed using above-water and underwater video cameras (120 Hz), and the coordinates of the body feature points using the 4-point conversion method were identified to calculate the kinematics. The results showed that 1) the time at which the head passed the 5-m point tended to be faster, 2) the center of gravity horizontal velocity at takeoff tended to be higher, and 3) the height of the greater trochanter when the fingertips entered the water tended to be higher for Original. These findings suggest that Original may improve starting performance compared with High.
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