Effects of task and environmental constraints on axial kinematic synergies during the tennis service in expert players

Abstract

The aims of this study were to examine the effects of task and environmental constraints on axial synergies and to find an association between synergies and arm acceleration as a performance variable. Participants of this study were 10 expert tennis players (age: 34.4±7.46) who voluntarily took part and executed 60 serves under two different conditions: no-opponent and opponent. An inertial motion unit (IMU) capture system was used to calculate the 3D angular joint motions in the neck, back and lumbar segments. The results of the principal component analysis showed that the redundancy in the axial segments is decomposed into 2 main synergies that are responsible for the loading (backward swing) and firing phase (forward swing). The total variance and loading synergy variance were significantly lower in the topspin service than other service types. The emerged firing synergy was strongly associated with the arm acceleration regardless of service type. In conclusion, the effective strategy to utilise the axial motions in the trunk is through creating functional synergies that have a flexible role based on the type of service and conditions. The topspin service showed less coordination variability relative to other types of service and serving in the opponent condition required participants to change the nature of synergy among the axial segments. These findings support the design of practice that emphasises the importance of more realistic contexts with special attention given to the order of different service types.

Skill Level in Tennis Serve Return Is Related to Adaptability in Visual Search Behavior

“…Interestingly, the first two AOIs, namely, tossing hand movement area and ball upward movement, were also the most important predictors of return performance category and individual server. These results are consistent with the observations of Jackson and Mogan ( 2007 ), who pointed out the importance of ball toss for ball flight anticipation, as well as observations that important kinematic synergies are typical for these phases and can be specific for an individual server (Shafizadeh et al, 2019 , 2020 ). Other AOIs located in the following phases of the movement of a server have been shown to contribute less to the classification of returning player and individual server.…”

“…Eye-tracking data were filtered using a raw filter without gap-fill interpolation and with noise reduction both available in the Tobii Pri Lab software. To assess the gaze behavior during the movement of a server, serve actions were categorized into the following five phases based on major serve events that also determine the important time frames for the emergence of movement synergies of servers (Shafizadeh et al, 2019(Shafizadeh et al, , 2020, which are defined by the organization of different body parts that work together to achieve a specific goal of the movement task and provide stability and flexibility of the system (Latash et al, 2007): (i) the preparation phase, starting 500 ms before and ending at the first observable upward movement of the tossing hand (preparation), (ii) the ball toss, ending at the instance the ball left the hand (ball toss), (iii) the windup phase, ending at an instance when the racket began to move upward, (iv) the hitting phase, ending when the racket contacted the ball, and (v) the follow-through phase, ending at an instance when the gaze of the participant started following the flying ball. In addition, 25 areas of interest (AOI) were defined according to the movement synergies present during the movement of servers (Jackson and Mogan, 2007;Shafizadeh et al, 2019) (Table 1), six in the first, nine in the second, three in the third, two in the fourth, and five in the fifth phase of servers movement.…”

Kinematics characteristics of key point of interest during tennis serve among tennis players: a systematic review and meta-analysis

“…The 27 articles selected cover 4 of the 5 continents (America, Asia, Europe, and Oceania) in 12 different countries. Seven studies were conducted solely on male tennis players ( 19 , 21 , 23 , 24 , 26 , 30 , 33 ), three studies included only female players ( 6 , 8 , 35 ), nine studies had a mixed population ( 1 , 3 , 11 , 13 , 20 , 22 , 25 , 31 , 36 ) and height did not provide this information ( 4 , 9 , 12 , 27 – 29 , 32 , 34 ). Different age categories were studied.…”

“…Different age categories were studied. Data were reported using the following designations: children, teenagers, prepubescent, pubescent, adults (ranging from 9.3 ( 25 ) to 34.4 ( 31 ) years). Several levels of expertise were also studied.…”

“…Reid and Giblin also studied the effect of the final position of the lower limb during the follow-through phase [normal vs. arabesque ( 12 )]. Four other studies investigated the effect of a specific condition: difference between two laboratories ( 32 ), racket size ( 11 ), wearing a postural shirt vs. a normal shirt ( 36 ), and with or without opponent ( 31 ).…”