Specific aspects of the physical training for the racket sports. Presented By Olivier GIRARD

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1 Specific aspects of the physical training for the racket sports Presented By Olivier GIRARD

2 Physical skills and components relevant to racket sports Major physical components ANAEROBIC AEROBIC AUXILLARY Speed Agility Strength Muscular endurance Power Aerobic endurance Body awareness /dynamic balance Flexibility Reaction time /anticipation Racket sport performance

3 OUTLINES Movement pattern in racket sports Strength training and neuromuscular adaptations Improving aerobic and anaerobic components Sport-Specific Incremental Tests High-Intensity Interval Training Repeated Sprint Training

4 Mechanical demands of racket sports A tennis player typically runs an average of 3 m per shot and a total of 8-12 m in the course of a point, completing high intensity efforts (2 to 3.5 km) during a best of three set match (Fernandez et al. 2009). The number of directional changes in an average point is four. About 80% of all strokes are played within 2.5 m of the player s ready position, while about 10% of strokes are made with m of movement with primarily a sliding type movement pattern. More than 70% of movements are side to side with less than 20% of movements in a forward direction and less than 8% of movements in a backward direction (Weber et al. 2007).

5 The development of racquet speed Stroke production requires a generation of high force and power outputs, through varying ranges of motion. The use of elastic energy (shoulder muscles) Affected by stroke technique (foot-up vs. foot-back) or performance level The distance over which racket speed can be developed The use of coordinated movements (proximo-to-distal sequencing) Contractions of the lower extremity musculature, and thus interaction of the feet with the court, produce the ground reaction forces (GRFs) central to successful stroke and movement production.

6 The development of racquet speed Proximo-to-distal sequencing Major contributors to racquet speed : Speed Racquet Shoulder internal rotation + wrist flexion (56%) (Elliott et al. 1986; Elliott et al. 1995) Kinematic chain Segment n Speed Racquet Segment 2 Segment 1 GRF Shoulder Elbow Wrist Time Hip Coordinated 3-D segmental rotations Time Optimal racquet position, trajectory and velocity at the impact

7 The development of racquet speed The use of elastic energy (Bahamonde, 1997; Elliott, 2002) Countermovement Acceleration of the upper arm segment shorte n muscle stretch muscle force with stretch without stretch joint angle Backswing = ECCENTRIC Forwardswing = CONCENTRIC Impact Shoulder EXTERNAL rotation Shoulder INTERNAL rotation

8 Lower limb electromyogram and ground reaction force profiles characterizing the tennis serve Leg power (W. kg - 1 ) Beginner (N = 7) 32 subjects 3 performance level groups Intermediate (N = 10) Elite (N = 15) Part A - Vertical jump testing Part B - 15 Power Serves Squat jumps Countermovement jumps Beginner I nt ermediat e Elit e Similar neuromuscular qualities between groups Lower extremities (GRF and EMG)

9 My changes (N. m - 1 ) Lower limb electromyogram and ground reaction force profiles characterizing the tennis serve Vmax (km. h - 1 ) *** 155 * * Beginner I nt ermediat e Elit e I height (% of st anding height ) Beginner I nt ermediat e Elit e 2, 7 * 1400 *** Fzmax (BW) 2, 4 2, 1 1, 8 1, , Beginner I nt ermediat e Elit e Beginner I nt ermediat e Elit e Correlation (r = 0.85; P < 0.001) between I height and Fz max in skilled players

10 Lower limb electromyogram and ground reaction force profiles characterizing the tennis serve Relat ive durat ion (%, t ot al serve durat ion) Suspension GRF Preparation Eccentric Concentric Initiation of the movement Knee flexion Knee extension Take-off Impact 100% ± s ± s ± s 80% 60% 40% 20% ** * Suspension Concent ric Eccent ric Preparat ion 0% Beginner I nt ermediat e Elit e Skilled players: Longer Preparation and shorter Concentric phases (no difference in total serve duration)

11 Lower limb electromyogram and ground reaction force profiles characterizing the tennis serve Electromyograms of successful performance in beginner and elite participants More refined neuromuscular coordination patterns (precocious EMG) distinguished the serves of elite players from those of their lower level counterparts.

12 Predictors of stroke effectiveness Strength is required in muscles and joints both for performance (ball velocity) enhancement and to reduce injuries (protection of joints, ligaments and tendons). Right rotation work (120.s) Right rotation work (60.s) Backhand medicine ball toss Forehand medicine ball toss Right rotation peak torque (120.s) Right rotation peak torque (60.s) Leftrotation work (120.s) Left rotation work (60.s) Left rotation peak torque (120.s) Left rotation peak torque (60.s) r = (Ellenbecker et al. 2004) Trunk rotation and flexion strength of elite junior players is significantly and positively associated with forehand and backhand medicine ball throwing distance.

13 Predictors of stroke effectiveness Serve ball velocity (mph) Isokinetics and on-court performance (Signorile et al. 2005) Knee extension Shoulder internal /external rotation Diagonal throwing motion 45 intermediate junior tennis players Isokinetic speeds = 0.785, 1.57, 3.14, 4.71, 7.85 (rad.s -1 ) Ball velocity Stroke Placement Isokinetic torque during diagonal throwing motion at 3.14 rad.s -1 (Nm) Serve, forehand, backhand However, no significant correlations between isokinetic variables and shot accuracy. Importance of movement specific strength training for increasing ball velocity.

14 Predictors of stroke effectiveness Ambiguity of the relations between strength measures and ball velocity: - Isokinetic internal/external rotation, wrist flexion/extension and forearm pronation strength (90, 210 and 300 deg.s -1 ) of the dominant arm not correlated to ball speed (Ellenbecker et al. 1991). - Leg, shoulder and wrist strength measures relate poorly to the serving speeds (Pugh et al. 2003) Methodological challenges in quantifying such relationships - Isokinetic testing still fails to replicate the actual velocities at which segments are rotated in stroke production. - Minimal effort has been made to ascertain whether measures other than peak torque/force (or maximum strength) like rate of force development, more meaningfully relate to the generation of racket velocity. - Powerful shots are likely a combination of strength, coordination, flexibility and technique.

15 Flexibility (Range Of Motion - ROM) Physical demands can cause musculoskeletal adaptation; = reduced joint ROM, changing biomechanical patterns, and the efficiency of force production, thus the risk of injury. Tennis players have a greater ROM for internal shoulder rotation than other athletes, but smaller external shoulder rotation (Chandler et al. 1990). A 4-month season of tennis play did not significantly change internal or external rotation strength or range of motion (Ellenbecker et al. 2002). = Practice is not enough! NS NS NS NS

16 TAKE HOME MESSAGES (1) #1 Training using specific movement patterns that are encountered during match play (e.g. focus training between 60 to 80% of the time on lateral movements, 10 to 30% of the time on linear forward movements, and only about 10% of the time on linear backward movement); using sprint activities that are no longer than the furthest distance that the athlete would run, per shot, during a point. #2 Adequate strength and range of motion are essential in preventing injuries. Both concentric and eccentric training (legs, shoulder) - at relatively fast functional velocities - is recommended. Conditioning programs should include exercises to facilitate and develop bilateral trunk rotation. Improve joint range of motion (e.g. shoulder external rotation) to fix the imbalanced created, while excessive flexibility training may induce negative outcome (reduced power output).

17 OUTLINES Movement pattern in racket sports Strength training and neuromuscular adaptations Improving aerobic and anaerobic components Sport-Specific Incremental Tests High-Intensity Interval Training Repeated Sprint Training

18 Strength training Maximum strength development with very high intensities (>85% 1RM) and low repetitions (1-5) Muscular power is needed for on court movement and stroke production (sprinting to the ball, reaching, jumping, lunging, changing directions, stopping, and starting.) Muscular endurance is required to maintain high levels of application throughout the entire match (= low intensity, high volume and short rest periods)

19 Moment-Velocity relationship Moment (N.m) TRAINING ECCCENTRIC -120.s s -1 ISOMETRIC 0 CONCENTRIC 60.s s -1 Velocities (.s - 1 )

20 Training & time course of underpinning neuromuscular adaptations EARLY LATE NERVOUS STRETCHING STRUCTURAL Recruitment Synchronization Elasticity Hypertrophy Fibers Coordination Reflex Sarcommers

21 Training & time course of underpinning neuromuscular adaptations Percentage (initial value) Resistance training BEFORE Position MVC EMG activity Contractility Moment EMG Position Moment AFTER EMG AFTER TRAINING Time (months) BEFORE

22 Rapid force characteristics Explosive muscle strength can be measured as the rate of force development during a maximal voluntary isometric contraction (Andersen et al. 2007) Moment EMG ms

23 Neuromuscular characteristics Knee extensor (quadriceps) and flexor (hamstring) torque-velocity characteristics and contractile rate of force development in elite badminton players (Andersen et al. 2007) Knee extensors Knee flexors Badminton players had greater maximal and explosive muscle strength. (adaptations from years of physical training)

24 Resistance training and rapid force characteristics 12 sessions of resistance training (plantar flexion isometric contractions) during 4 weeks (+42%) 38 sessions (5 series 3 to 10 repetitions) of resistance training (plantar flexion concentric contractions) during 14 weeks Del Balso et al Aagaard et al. 2002

25 Electromyostimulation (ES) 9 sessions of quadriceps ES (16 min) strength training during 3 weeks incorporated into tennis sessions during the preparatory seasons of competitive players SJ Progressive ES strength training may be safely included in the early tennis season and can lead to improvements in the anaerobic performance.

26 Plyometric training 8 sessions of plyometric jumps during 4 weeks in competitive women JUMP TESTS TENNIS SERVE Stretch-shortening cycle Countermovement Squat Jump Jump (24 to 26 cm) (22 to 24 cm) = Leg power Muscle contractility ( Force production) Muscle elasticity ( Force transmission) Serve velocity (+3%) Peak vertical force (952 to 1144 N)

27 TAKE HOME MESSAGES (2) #3 Players may develop strength and power without concomitant hypertrophy, increase local muscular endurance, prevent detraining and potentially reduce the risk of injury. Ideal in-season resistance training platform should include a minimum of two training sessions per week, alternating complex with muscular endurance training sessions

28 OUTLINES Movement pattern in racket sports Strength training and neuromuscular adaptations Improving aerobic and anaerobic components Sport-Specific Incremental Tests High-Intensity Interval Training Repeated Sprint Training

29 Evaluating aerobic fitness Ventilatory and metabolic parameters Laboratory tests = Reproducible and valid procedures Utilisation: Determine aerobic potential (aerobic power and capacity) [La] VT1 VT2. VE.. VE/VO 2.. VE/VCO 2 Intensity Identify target training areas (intensity zones ) Evaluate the effects of various training procedures (athlete progress)

30 Maximal oxygen uptake (VO 2max ) Maximal oxygen uptake (VO 2max ) values of French national teams (INSEP) m 3000 et 5000 m Middle-distance Road cycling Wlak (20 & 50 km) Middle distance Cycling Ice skating Orienting Rowing Pentathlon modern Skating (artistic) Boxing Skating (speed) Skating Sprint 400m Trampoline Swimming Judo Football Walk Alpine skying Kayak Decathlon Sprint 100 & 200 m Water polo Karate Basket-ball Golf Sailing Fencing Handball Rubgy Hockey (ice) Hockey (grass) Weight lifting Volley-ball Car drivers Kayak 65,4 64,6 64, ,4 60,8 60,5 59,3 59,1 59,1 58,6 58,1 58,1 57,9 57,7 57,6 57,3 57,3 57, ,8 56,3 55,5 54,4 54,4 53,6 52,9 52,2 71, ,9 69,1 68,8 68,6 67,9 75,5 77, , VO 2max (ml/min -1 /kg -1 )

31 VO 2max and racket sports VO 2max (ml.kg -1.min -1 ) Table tennis Tennis Badminton Squash Low High Moderate to high aerobic capacities (similar to team sports)

32 Evaluating aerobic fitness Laboratory tests have different mode of exercise and specific muscular involvement Treadmill (laboratory) Tennis (field) Continuous nature Forward running (no lateral displacements) Limited involvement of upper limbs Start and stop nature (intermittent) Multidirectional movements with changing pace/intensity Repeated dynamic upper (and lower) limbs movements

33 Evaluating aerobic fitness Development of a tennis-specific incremental test Progressive (incremental - Stages) Maximal (until exhaustion) Specific (including elements of tennis play) - Performed on a tennis court - Similar displacement technique to competition - Simulation of ball hitting - Randomized direction of motion - Visual feedback Multidirectional and incremental test consisting in repeated displacements simulating the game of tennis on the court Evaluation of aerobic fitness

34 Test protocol 3.60 m 1.20 m 0.80 m Multidirectional and incremental test consisting in repeated displacements simulating the game of tennis on the court 1.80 m C PLAYER 1.20 m Each stage Seven shuttle runs (randomly) From a central base to one of six targets located around the court 2 forward (offensive) 3 lateral (neutral) 2 backward (defensive) Alternated with 15 s of passive recovery

35 Test protocol Movement velocities and directions to the players Specialized software (PC) Simultaneously activate a tune and project a picture of a player moving towards the target (x 7) Duration of the first sequence: 40.5 s, by steps of 0.8 s for each stage

36 Test protocol Same running and mime of stroke technique as in competition 1 Movement direction 3 Mime of a powerful stroke 5 Movement direction 2 4 Displacement Repositioning 6 Passive recovery (15 s) Tests ends when: - Player fail to reach the target in time (that is, a > 1 m delay occurs) - Mime strokes with acceptable technique Objective criteria - A final HR > 95% of the age related maximum, - A final [La] > 8 mmol/l -1, - A final RPE > 18 points.

37 Determining target intensity zones Heart rate (bpm) «Anaerobie» zone «Aero-anaerobic» zone «Aerobic» zone «Warm-up» zone Progressive workload increase HR = 140 bpm HR = 165 bpm HR = 180 bpm HR = 192 bpm 460 s 1080 s 1400 s 1560 s = Stage 5 = Stage 17 = Stage 24 = Stage 28 Time (s)

38 Using the training software Specific training environment including a strict control of work-load intensity (ou repetitions) (ou series)

39 Tennis specific incremental test - Main results VO 2max (ml/min -1 /kg -1 ) Ventilatory Threshold Respiratory Compensation Point Parameters Laboratory Field Laboratory Field %HR max 83.0 (2.8) 83.6 (5.1) NS 92.3 (2.1) 92.1 (2.1). %VO2 max 73.5 (6.1) 69.4 (8.1) NS 85.5 (8.7) 84.4 (6.5) NS NS Physiological training intensity zones for tennis on-court aerobic exercises can be accurately prescribed using treadmill tests.. 66 * LABORATORY 63.8 FIELD. VO 2max Laboratory (ml/min -1 /kg -1 ) VO 2max FIELD (ml/min -1 /kg -1 ) Maximum oxygen uptake derived from laboratory testing is not relevant for accurately estimating one player s fitness level

40 Practical implication of the field test Main results: Using field testing in addition to treadmill testing should be (1) No difference between FTprescribe and TT for submaximal physiological used to accurately tennis on-court aerobic exercises.variables (%HRmax and %VO2max). (2) FT VO2max values were higher than TT values Benefits of the present FT: (1) Reproducible (CV < 5%) (2) Specific demand upon the player Combined with the training of sport-specific technical elements (3) Specific to tennis game ( motivation) - Performed on a tennis court (4) Easily administrated limited equipment and inexpensive - Similar displacement technique to competition - Randomized direction of motion - Simulation of ball hitting performance level (5) Adapted tothe each player s (6 cones and a portable PC (++ when weekly including the software of the test) training time is limited) Perspectives: FT should be used to.. - Judge of the efficiency of different training regimens (i.e. intermittent methods) - Analyse the effects of factors that could affect tennis performance (i.e. supplementation, drinking regimens)

41 Squash specific incremental test Te (s) y = x R 2 = 0.90 N = cm m m cm m Competition ranking order VT RCP Max Variables TT ST TT ST TT ST VO 2 (ml. min. kg -1 ) 45.8 ± ± 2.5 ** 50.5 ± ± 3.9 ** 54.9 ± ± 3.0 *** %VO 2max 83.2 ± ± ± ± %HR max 86.0 ± ± ± ± Using the squash tests to i) Assess performance level and ii) Prescribe physiological training intensity zones for on court squash training. Girard et al. (2005)

42 OUTLINES Movement pattern in racket sports Strength training and neuromuscular adaptations Improving aerobic and anaerobic components Sport-Specific Incremental Tests High-Intensity Interval Training Repeated Sprint Training

43 Speed endurance and repeated-sprint ability (RSA)-based training = Maximal or near-maximal short-term efforts (Repeated sprints) with minimal recovery between sprint bouts (i.e., maximal sprints or shuttle sprints of 10 seconds, with brief recovery periods ( 60 seconds); work:rest ratio of 1:4 1:6) anaerobic enzymes activity aerobic enzymes activity rate of anaerobic energy turnover the number of muscle membrane transport proteins involved in ph regulation and muscle capilarization muscle buffering capacity VO 2max

44 Pre-tests Post-tests Speed endurance and repeated-sprint ability (RSA)-based training 3 x [7 min repeated sprints 5 min rest] 24 competitive tennis players Short RS (5s - 20s) Medium RS (10s - 20s) Long RS (15s - 20s) Control Eicher et al. 2006

45 Speed endurance and repeated-sprint ability (RSA)-based training Improvement (%) Improvement (%) Combined with technical elements of the game, repeated sprint training (5,10 and 15s 20 s) +++ RSA and tennis-specific endurance Test 12 x 5-20 Test 12 x Test 12 x % (P<0.05) * * +8.2% (P<0.001) * * +6.8% (P<0.01) * * Tennis specific incremental test G 5-20 G G G C * * * G 5-20 G G G C 0 Pré-test Post-test Groups The involvement of the same muscles (acceleration and deceleration movements) could lead players to positive changes in specific coordination and agility during the RSA test

46 High-intensity interval training (HIIT) Characteristics: - Work and rest intervals ranging from 15 seconds to 4 minutes % velocity associated with VO 2max - Heart rate values > 90% HR max - Work-to-rest ratios of 1:1-4:1 in cardiovascular parameters (heart size, blood flow capacity, and artery distansibility) Capacity of the cardiovascular system to transport oxygen = Faster muscle and pulmonary VO 2 kinetics and higher VO 2max Hence, a greater amount of energy can be supplied aerobically, allowing a player to both sustain intense exercise for longer durations and also recover more rapidly between high-intensity phases of the game (Hazzell et al. 2010) Effective training strategy to enhance the aerobic capacity without negatively affecting strength, power, or sprint performance (Iaia et al. 2009).

47 High-intensity interval training vs. repeated sprint training in tennis

48 High-intensity interval training vs. repeated sprint training in tennis Both training interventions showed similar improvements in general aerobic fitness The resynthesis of PCr is related to aerobic fitness (% 4mM or LT) PCr Resynthesis (%) R 2 = mm (% VO 2 max) Bogdanis et al. (1996)

49 High-intensity interval training vs. repeated sprint training in tennis SPECIFICITY OF TRAINING! Repeated Sprint Training induces greater in RSA (specific coordination/agility changes) High-Intensity Interval Training induces greater in tennis-specific endurance Both training modalities jumping and sprinting abilities

50 Speed and agility Assessment of the relationship between speed and agility parameters in tennis players (Leone et al. 2006) Lack of relationship among the different type of running velocity tests (r 2 < 20%) Running speed and agility are specific qualities, most of the time unrelated, and have limited transfer to one another.

51 Strength Speed, vertical power abilities, and maximal strength in the dominant side are significantly correlated with tournament play performance in competitive teenager tennis players (Girard & Millet, 2009). Unlike the asymmetrical differences seen in upper body strength, lower body strength measures have been shown to be symmetrical in racket sport players.

52 TAKE HOME MESSAGES (3) #4 The inclusion of either high-intensity interval training or repeated-sprint training programs, 3 times per week, to normal tennis training sessions represents an effective means of increasing cardiorespiratory fitness (VO 2max ) in high-level tennis players (Fernandez Fernandez et al. 2011). #5 Repeated sprint training (i.e., 3 x [10 x 15 seconds] shuttle sprints, with 20-second rest between repetitions, 3 min rest between sets) +++ to repeated sprint ability #6 High-Intensity Interval Training (i.e., 3 x [3 x 90 seconds, 90 95% HR max ], with 3-minute rest) +++ to activity-specific aerobic fitness #7 Lack of improvement in sprinting and jumping using those two different training protocols => additional resistance training needed!

53 Training, buffer capacity and RSA How best to improve muscle buffer capacity? Aerobic (< LT) Interval (30 s all-out sprint: 4 min recovery) Interval (2 ~ 80%VO2max: 1 min recovery) Interval (2 ~ 90%VO2max: 1 min recovery) Repeated Sprint Training (matched work with interval) Interval (2 ~ 100%VO2max: 1 min recovery) Change in muscle buffer capacity (umol H +.g -1 dw.ph -1 ) Edge, Bishop et al. (2005). EJAP. 96: Harmer et al. (2000). JAP. 89: Edge & Bishop. (2006). JAP. 101: Edge & Bishop. (2008). Am J Phys. In Review. Bishop et al. (2008). Unpublished.

54 Training, buffer capacity and RSA Work (J) Muscle Buffer Capacity Interval Training 2 80% VO 2max with 1 min recovery between intervals Continuous Training Same total work 90% lactate threshold 3/weeks during 5 weeks Accumulation of H Pre-Train - CONT Pre-Train - INT Post-Train - CONT Post-Train - INT H + Production Buffer Capacity (β) Cont Interval * Sprint Number Edge et al. (2005) 20 Pre-Train Post-Train High-Intensity Interval (but not continuous) Training induces in muscle buffer capacity

55 How best to improve VO 2max? Aerobic (< LT) Interval (2 ~ 80%VO2max: 1 min recovery) Interval (2 ~ 90%VO2max: 1 min recovery) Interval (2 ~ 100%VO2max: 1 min recovery) Interval (4-10 x 30-s all-out sprint: 4 min recovery) Small-sided games Repeated Sprint Training (matched work with interval) Change in VO 2max (ml/kg/min) Edge, Bishop et al. (2005). EJAP. 96: Edge & Bishop. (2006). JAP. 101: Edge & Bishop. (2008). Am J Phys. In Review. Impellizzeri et al. (2006). IJSM. 27: Harmer et al. (2000). JAP. 89: Bishop et al. (2008). Unpublished.

56 [PCr] (mmol.kg -1 dw) [PCr] (mmol.kg -1 dw) Training and PCr resynthesis Training Post-training (5 wk: 6-12 x 2 min 5 weeks: 6-12 x 2 ~90-100% VO2max: 1 min rest) 100% VO 2max : 1 min rest Pre-training * * Training 7 weeks: 3 x / wk 3-10 x 30-s: 3-4 min rest s sprint Rest Post +1 min +3 min s sprint Rest Post Post-training Pre-training + 3 min lactate threshold (12-20%) No VO 2max High-intensity interval training, that improves VO 2max and the lactate threshold, can improve short-term PCr resynthesis

57 TAKE HOME MESSAGES (4) To more effectively resist to fatigue: #8 It seems important to include (i) some training to improve single-sprint performance. This should include i) specific sprint training; ii) strength/power training and iii) occasional high intensity (>VO 2max ) training (repeated, 30-s, all-out efforts separated by 10 min of recovery) to increase the anaerobic capacity. #9 It seems important to include (i) some interval training to best improve the ability to recover between sprints. This should include some high-intensity (~80-90% VO 2max ) interval training, interspersed with rest periods (1 minute) that are shorter than the work periods (2 minutes) to improve aerobic fitness (VO 2max, lactate threshold), the rate of Pcr resynthesis and muscle buffer capacity (Bishop et al. 2011). #10 Training harder is not always better!

58 Periodization Complex bio-energetic nature of match play Intensive calendars, punctuated by weekly inter-continental travel with uncertain playing times Challenge in the planning of specific strength and conditioning interventions

59 Detraining Periodization of resistance training over 9 months is superior for enhancing strength and motor performance in collegiate women tennis players (Kraemer et al. 2000) Essential for optimization of resistance- training programs

60 Detraining A 5 week interruption of normal training results in significant in speed, power and aerobic capacity in competitive tennis players (Kovacs et al. 2007)

61 Thank you! Questions?