Differences in the key parameters of the individual versus relay swimming starts

Abstract

The purpose of the present study was twofold: (i) to compare the kinematic characteristics of individual and relay swimming starts; and (ii) to relate the kinematic variables to 5 m performance for both starts. Twelve elite-level swimmers performed 2 × 25 m at maximal effort (one with an individual and one with a relay start randomly). Two-dimensional direct linear transformation algorithms were used to calculate swimmers' centre of mass (CM) kinematics during each subphase. The results indicated moderate to much faster 5 m, 10 m 15 and 15 m times (29.4, 10.7 and 6.5%) for relay than individual starts as well as the differences at specific parameters, but no differences in take-off horizontal velocity between start techniques. Large correlations to performance times were found in block time, horizontal takeoff velocity, take-off velocity and entry angle (r = 0.77 to 0.83) 20 for individual start, but in changeover time, take-off height and entry distance (r = 0.69 to 0.90) for relay start. Differences on swim start regulations between individual and relay events were in line with different key parameters related to start performances in each event. This should be considered by swimmers and coaches when addressing the starting improvement.

Comparison of Starts and Turns between Individual and Relay Swimming Races

“…In the start segment, swimmers participating in the 100 m events of the European Junior Swimming Championships globally performed 6.22 ± 0.14% faster 15 m times in relays than in individual events. This was in line with previous differences observed under experimental setup conditions [ 4 ] and it was accompanied by differences in each of the start subsections except the flight phase. The reason was potentially the different start regulations in relay versus individual events.…”

“…However, faster 15 m times in relay starts did not reflect a superior performance in each start section. In the flight phase, swimmers presented similar average flight distances and times when racing in individual or relay events ( Figure 1 ), despite previous results where international-level swimmers presented longer centre of mass dive distances when performing relay starts in an experimental setup [ 4 , 12 ]. Although preparatory block movements on relay starts should theoretically lead to a longer flight distance [ 27 , 28 ], the present results suggest that swimmers do not profit from them when competing.…”

“…This is consistent with previous results showing slower start performances in relay starts if specific training was not conducted [ 12 ]. The reason for this is probably the different swimmers’ body posture and centre of mass position at the instant of take-off and water entry in relays [ 4 ], which may have several implications for the subsequent underwater swimming. Modifications of the entry width (horizontal distance from hand to feet water entry) could result in variations in the trajectory while underwater and to an increase in the drag forces [ 29 ] (pp.…”

“…From a biomechanical point of view, individual and relay starts present some spatiotemporal differences in the swimmers’ centre of mass during the aerial phase. However, no differences in take-off velocities have been observed [ 4 ]. Additionally, the kinematic start parameters related to 5 m performance times do not coincide between both techniques as the change-over times, take-off height, and entry distance are largely related to the start performances in relays [ 4 ].…”

Predicting performance in 4 x 200-m freestyle swimming relay events

“…In swimming, key considerations for relay team performance include flying start technique and exchange block times [4][5][6]. As a result, much of the relay literature in swimming focuses on technical components related to the dive start, including differences between the flat start performed in individual events and the flying start performed by swimmers assigned to the second to fourth relay positions [7,8]. However, in both track running and swimming, it appears that selecting the fastest athlete for the first or lead-off relay leg is popular and successful [1][2][3], although further research is required to determine how this impacts team performance.…”