Isabelle Rogowski

Influence of fatigue on upper limb muscle activity and performance in tennis

The study examined the fatigue effect on tennis performance and upper limb muscle activity. Ten players were tested before and after a strenuous tennis exercise. Velocity and accuracy of serve and forehand drives, as well as corresponding surface electromyographic (EMG) activity of eight upper limb muscles were measured. EMG and force were also evaluated during isometric maximal voluntary contractions (IMVC). Significant decreases were observed after exercise in serve accuracy (-11.7%) and velocity (-4.5%), forehand accuracy (-25.6%) and consistency (-15.6%), as well as pectoralis major (PM) and flexor carpi radialis (FCR) IMVC strength (-13.0% and -8.2%, respectively). EMG amplitude decreased for PM and FCR in serve, forehand and IMVC, and for extensor carpi radialis in forehand. No modification was observed in EMG activation timing during strokes or in EMG frequency content during IMVC. Several hypotheses can be put forward to explain these results. First, muscle fatigue may induce a reduction in activation level of PM and forearm muscles, which could decrease performance. Second, conscious or subconscious strategies could lead to a redistribution of muscle activity to non-fatigued muscles in order to protect the organism and/or limit performance losses. Otherwise, the modifications of EMG activity could also illustrate the strategies adopted to manage the speed-accuracy trade-off in such a complex task.

Relationship between muscle coordination and forehand drive velocity in tennis

This study aimed at investigating the relationship between trunk and upper limb muscle coordination and stroke velocity during tennis forehand drive. The electromyographic (EMG) activity of ten trunk and dominant upper limb muscles was recorded in 21 male tennis players while performing five series of ten crosscourt forehand drives. The forehand drive velocity ranged from 60% to 100% of individual maximal velocity. The onset, offset and activation level were calculated for each muscle and each player. The analysis of muscle activation order showed no modification in the recruitment pattern regardless of the velocity. However, the increased velocity resulted in earlier activation of the erector spinae, latissimus dorsi and triceps brachii muscles, as well as later deactivation of the erector spinae, biceps brachii and flexor carpi radialis muscles. Finally, a higher level of activation was observed with the velocity increase in the external oblique, latissimus dorsi, middle deltoid, biceps brachii and triceps brachii. These results might bring new knowledge for strength and tennis coaches to improve resistance training protocols in a performance and prophylactic perspective.

Physical outcome in a successful Italian Serie A soccer team over three consecutive seasons.

Abstract Vigne, G, Dellal, A, Gaudino, C, Chemari, k, Rogowski, I, Alloatti, G, Wong, PD, Owen, A, and Hautier, C. Physical outcome in a successful Italian Serie A soccer team over three consecutive seasons. J Strength Cond Res 27(5): 1400–1406, 2013—The aim of this study was to examine the physical performance of a successful Italian Serie A team of more than 3 consecutive seasons. Twenty-five players participated in the study and were classified into 3 playing positions: defenders (n = 9), midfielders (n = 11), and forwards (n = 5). Activities match were studied by an analysis of multiple match camera SICS throughout the competition Italian Serie A matches played at home (n = 90) for 3 consecutive seasons (first: 2004/2005; second: 2005/2006; and third: 2006/2007). Total team ball possession and time-motion characteristics were examined. Results showed that total ball possession (52.1–54.9%) and the number of points accumulated at home (40/48) improved in the past 3 seasons, whereas the final rankings at home were stable. The total distances covered by minutes of play were significantly different between the 3 seasons (118.32 ± 6.69 m·min−1 to 111.96 ± 8.05 m·min−1). Distance running and high-intensity activities were similar in the 3 seasons, whereas the distance covered in moderate-intensity running decreased in the third (p < 0.05). Variations between playing positions were found during the 3 consecutive seasons, with midfielders covering greater distances than defenders (p < 0.05) and forwards (p < 0.01). This study showed how for 3 consecutive seasons a Serie A team of successful players reduced their distances performed at submaximal speeds, and increased ball possession, while maintaining the high-intensity activities and the number of points at home. It is suggested that this is because of a better understanding of roles and tactics team organization and to act collectively and individually on these parameters to reduce energy expenditure during the game to maintain a high-level performance throughout the season.

Relationship between muscle coordination and racket mass during forehand drive in tennis

This study aimed at investigating the relationship between the trunk and upper limb muscle coordination and mass of the tennis racket during forehand drive. A total of 15 male tennis players performed seven series of ten crosscourt forehand drives, both with their personal racket and six rackets with increased mass ranging from 6 to 16% (stepxa0=xa02%) of their personal racket mass. The electromyographic (EMG) activity was recorded from nine trunk and upper limb muscles. The onset before impact and EMGrms values of the bursts were individually calculated. Results showed that the ball speed and the muscle activation temporal sequences were similar, whatever the increase in racket mass. Interestingly, in all participants, the activation level of the pectoralis major, latissimus dorsi and biceps brachii decreased when the racket mass increased, while the variations in the anterior deltoid activation level were correlated to the individual personal racket mass. These findings strongly suggest that the study of muscle activity during tennis practice should be considered as a complementary technique to determine a better adequacy of the racket characteristics to those of the player.

Reliability of EMG normalisation methods for upper-limb muscles.

Abstract The study investigated different electromyographic (EMG) normalisation methods for upper-limb muscles. This assessment aimed at comparing the EMG amplitude and the reliability of EMG values obtained with each method. Eighteen male tennis players completed isometric maximal voluntary contractions and dynamic strength exercises (push-ups and chin-ups) on three separate test sessions over at least 7 days. Surface EMG activity of nine upper body muscles was recorded. For each muscle, an analysis of variance for repeated measures was used to compare maximal EMG amplitudes between test conditions. The intra-class correlation coefficient, the coefficient of variation and the standard error of measurement were calculated to determine the EMG reliability of each condition. On the basis of a compromise between maximal EMG amplitude and high reliability, the chin-ups appeared to be the optimal normalisation method for M. latissimus dorsi, M. posterior deltoid, M. biceps brachii, M. flexor carpi radialis and M. extensor carpi radialis. The push-ups seemed relevant to normalise M. anterior deltoid and M. triceps brachii activity, while isometric maximal voluntary contraction remained the most appropriate method for M. pectoralis major and M. middle deltoid. Thus, original methods are proposed to normalise EMG signal of upper-limb muscles.

Effects of two training protocols on the forehand drive performance in tennis.

Abstract Genevois, C, Frican, B, Creveaux, T, Hautier, C, and Rogowski, I. Effects of two training protocols on the forehand drive performance in tennis. J Strength Cond Res 27(3): 677–682, 2013—The aim of this study was to examine the effects of 2 training modalities on the tennis forehand drive performance. Forty-four tennis players (mean ± SD: age = 26.9 ± 7.5 years; height = 178.6 ± 6.7 cm; mass = 72.5 ± 8.0 kg; International Tennis Number = 3) were randomly assigned into 3 groups. During 6 weeks, the first group performed handled medicine ball (HMB) throws included in the regular tennis practice, the second group (overweight racket—OWR) played tennis forehand drives with an overweighed racket during the regular tennis practice, and the third group (regular tennis training—RTT) practiced only tennis training as usual. Before and after the 6-week program, velocity and accuracy of tennis crosscourt forehand drives were evaluated in the 3 groups. The main results showed that after 6-week training, the maximal ball velocity was significantly increased in HMB and OWR groups in comparison with RTT (p < 0.001 and p = 0. 001, respectively). The estimated averaged increase in ball velocity was greater in HMB than in OWR (11 vs. 5%, respectively; p = 0.017), but shot accuracy tended to be deteriorated in HMB when compared with OWR and RTT (p = 0.043 and p = 0.027, respectively). The findings of this study highlighted the efficiency of both training modalities to improve tennis forehand drive performance but also suggested that the HMB throws may be incorporated into the preseason program preferably, whereas the OWR forehand drives may be included in the on-season program.

Implementation of Motor Imagery during Specific Aerobic Training Session in Young Tennis Players

The aim of this study was to investigate the effects of implementing motor imagery (MI) during specific tennis high intensity intermittent training (HIIT) sessions on groundstroke performance in young elite tennis players. Stroke accuracy and ball velocity of forehand and backhand drives were evaluated in ten young tennis players, immediately before and after having randomly performed two HIIT sessions. One session included MI exercises during the recovery phases, while the other included verbal encouragements for physical efforts and served as control condition. Results revealed that similar cardiac demand was observed during both sessions, while implementing MI maintained groundstroke accuracy. Embedding MI during HIIT enabled the development of physical fitness and the preservation of stroke performance. These findings bring new insight to tennis and conditioning coaches in order to fulfil the benefits of specific playing HIIT sessions, and therefore to optimise the training time.

Scapulothoracic kinematics during tennis forehand drive

Scapular dyskinesis is recognized as an abnormality in the kinetic chain; yet, there has been little research quantifying scapular motion during sport tasks. Tennis forehand drives of eight highly skilled tennis players were studied to assess the scapulothoracic kinematics and evaluate repeatability using video-based motion analysis. Scapulothoracic downward/upward rotation, posterior/anterior tilt, and internal/external rotation were computed using an acromial marker cluster. On average, the upward rotation, anterior tilt, and internal rotation varied from 1° to 26°, from 7° to 32°, and from 42° to 100°, respectively, during the tennis forehand drive. During the backswing and forward swing phases of the forehand stroke, small changes were observed for the three scapular angle values, while all angles increased rapidly during the follow-through phase. This suggests that the tennis forehand drive may contribute to scapula dyskinesis, mainly due to the great amplitude in scapulothoracic anterior tilt and internal rotation observed during the follow-through phase. Knowledge of normal scapula motion during sport tasks performed at high velocity could improve the understanding of various sport-specific adaptations and pathologies.

Upper limb joint muscle/tendon injury and anthropometric adaptations in French competitive tennis players

Abstract The purpose of this study was to examine the relationship between the upper limb anthropometric dimensions and a history of dominant upper limb injury in tennis players. Dominant and non-dominant wrist, forearm, elbow and arm circumferences, along with a history of dominant upper limb injuries, were assessed in 147 male and female players, assigned to four groups based on location of injury: wrist (n = 9), elbow (n = 25), shoulder (n = 14) and healthy players (n = 99). From anthropometric dimensions, bilateral differences in circumferences and in proportions were calculated. The wrist group presented a significant bilateral difference in arm circumference, and asymmetrical bilateral proportions between wrist and forearm, as well as between elbow and arm, compared to the healthy group (6.6 ± 3.1% vs. 4.9 ± 4.0%, P < 0.01; −3.6 ± 3.0% vs. −0.9 ± 2.9%, P < 0.05; and −2.2 ± 2.2% vs. 0.1 ± 3.4%, P < 0.05, respectively). The elbow group displayed asymmetrical bilateral proportions between forearm and arm compared to the healthy group (−0.4 ± 4.3% vs. 1.5 ± 4.0%, P < 0.01). The shoulder group showed significant bilateral difference in elbow circumference, and asymmetrical bilateral proportions between forearm and elbow when compared to the healthy group (5.8 ± 4.7% vs. 3.1 ± 4.8%, P < 0.05 and −1.7 ± 4.5% vs. 1.4 ± 4.3%, P < 0.01, respectively). These findings suggest that players with a history of injury at the upper limb joint present altered dominant upper limb proportions in comparison with the non-dominant side, and such asymmetrical proportions would appear to be specific to the location of injury. Further studies are needed to confirm the link between location of tennis injury and asymmetry in upper limb proportions using high-tech measurements in symptomatic tennis players.

How Does the Scapula Move during the Tennis Serve

PURPOSEnThis study aimed to describe the scapulothoracic kinematics during the tennis serve in highly skilled tennis players.nnnMETHODSnThirteen male competitive players performed flat first serves while eight high-speed cameras recorded the three-dimensional trajectories of the 15 markers located on bony landmarks. The scapular position through the tennis serve was determined using the acromial marker cluster method.nnnRESULTSnThe results revealed that, during the cocking phase, the scapula externally rotated and posteriorly tilted to attain the maximal humeral external rotation. During the acceleration phase, the scapula upwardly rotated and anteriorly tilted to reach maximal racket head height. During the follow-through phase, the scapula internally and downwardly rotated, and posteriorly tilted, while the upper limb lowered and crossed the players body.nnnCONCLUSIONSnThe findings of this study provide new knowledge on the asymptomatic scapular motion during the tennis serve, which may help clinicians and coaches to understand the overhead sport motion mechanics and to better prevent and rehabilitate overhead shoulder injuries.