The interaction between the tennis court and the player: how does surface affect leg stiffness?

Medical withdrawals in elite tennis in reference to playing standards, court surfaces and genders

OBJECTIVES

To examine the relationships between medical withdrawals, playing standards, court surfaces and genders in tennis players participating in all elite tours.

DESIGN

Descriptive epidemiology study.

METHODS

Medical withdrawals of men and women tennis players from Association of Tennis Professionals, Women Tennis Association, Challengers and International Tennis Federation Futures tours' matches have been identified considering the court surfaces (fast vs. slow). Proportion comparison and the binomial regression model were used to determine the influence of playing standards, court surfaces and genders on tennis players' likelihoods to withdraw.

RESULTS

A higher proportion of withdrawals was found for men in Challengers and Futures vs. Association of Tennis Professionals (4.8 %, 5.9 % vs 3.4 %; p < 0.001), but without difference between court surfaces (0.1 %, p > 0.05) whatever the playing standards. Women reported higher proportion of medical withdrawals sustained on slow surfaces (0.4 %, p < 0.001), but without different withdrawal rates between playing standards (3.9 %, p > 0.05). After adjustment, the odds of medical withdrawals were higher for Challengers (1.18, p < 0.001) and Futures (1.34, p < 0.001), with a higher likelihood to withdraw (1.04, p < 0.001) when playing on slow surfaces and with a gender-dependent effect indicating higher odds (1.29, p < 0.001) to withdraw for medical reasons in men in reference to women.

CONCLUSIONS

These findings demonstrated a gender-dependent effect on medical withdrawals from an elite tennis tournament with higher likelihood for men participating in Challengers/Futures tours and for women playing on slow surfaces.

Determining Stroke and Movement Profiles in Competitive Tennis Match-Play From Wearable Sensor Accelerometry

ABSTRACT

Perri, T, Reid, M, Murphy, A, Howle, K, and Duffield, R. Determining stroke and movement profiles in competitive tennis match-play from wearable sensor accelerometry. J Strength Cond Res XX(X): 000-000, 2023-This study determined stroke and movement accelerometry metrics from a wearable sensor and compared between court surface (grass vs. hard) and match outcome (win vs. loss) during competitive tennis match-play. Eight junior high-performance tennis players wore a trunk-mounted global positioning system, with in-built accelerometer, magnetometer, and gyroscope during singles matches on hard and grass courts. The manufacturer software calculated accelerometer-derived total player load (tPL). A prototype algorithm classified forehands, backhands, serves, and "other" strokes, thereby calculating stroke PL (sPL) from individual strokes. Movement PL (mPL) was calculated as the difference between tPL and sPL, with all metrics reported as absolute and relative (min -1 , %, and ·stroke). Analysis of accelerometer load and stroke count metrics was performed through a two-way (surface [grass vs. hard] × match outcome [win vs. loss]) analysis of variance ( p < 0.05) and effect sizes (Cohen's d ). No interaction effects for surface and match outcome existed for absolute tPL, mPL, and sPL ( p > 0.05). Increased mPL% featured on grass courts, whereas sPL% was increased on hard courts ( p = 0.04, d = 1.18[0.31-2.02]). Elevated sPL·min -1 existed on hard courts ( p = 0.04, d = 1.19[0.32-2.04]), but no differences in tPL·min -1 and mPL·min -1 were evident for surface or outcome ( p > 0.05). Relative forehand sPL (FH-sPL·min -1 ) was higher on hard courts ( p = 0.03, d = 1.18[0.31-2.02]) alongside higher forehand counts ( p = 0.01, d = 1.29[0.40-2.14]). Hitting demands are heightened on hard courts from increased sPL and counts. Conversely, increased mPL% on grass courts likely reflects the specific movement demands from point-play. Physical preparation strategies during training blocks can be tailored toward movement or hitting loads to suit competitive surfaces.

Risk Factors for Upper Limb Injury in Tennis Players: A Systematic Review

Studies in tennis injuries have successfully identified the incident rate, the location, and the type of the injury. The majority of the studies have multiple perspectives (epidemiology, biomechanics, performance), however only a few studies were able to identify risk factors or mechanisms that contribute to tennis injuries. Until now, there has not been a systematic literature review that identifies risk factors for tennis injuries. The objective of this review was to identify and critically appraise the evidence related to risk factors for upper limb injury in tennis players. A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework, using a research question developed by the Patient Problem, (or Population) Intervention, Comparison or Control, and Outcome (PICO) methodology. The quality of the studies included was moderate to low, indicating prolonged tennis (exposure to tennis), scapular dyskinesis, muscle fatigue, scapulothoracic properties, shoulder kinetics or kinematics, skill level, and technique as risk factors for upper limb injury in tennis players. In this review, it is evidenced that the majority of tennis injuries are associated with overuse and a chronic time course, however, tennis injuries do not arise from a linear combination of isolated and predictive factors. Therefore, the multifactorial and complex nature of tennis injuries has to be further examined. The necessity of more randomized control trial studies is highly recommended.

Relationship between split-step timing and leg stiffness in world-class tennis players when returning fast serves

This study investigated split-step timing when returning serves and whether this timing is related to neuromechanical capabilities in world-class tennis players. In Experiment 1, the split-step timing of four groups of world-class players (male and female ATP/WTA seniors, and ITF juniors) was measured on court when returning serves of the same level players. The four groups initiated the split-step at a similar time, starting around the time ball-racket contact in the serve stroke and landed when early ball-flight information was available. In Experiment 2, the neuromechanical capabilities (leg stiffness and vertical jump performance) of a group of world-class players and three groups of less-skilled tennis players were examined. The results showed an increase in leg stiffness with an increase in the level of expertise. A cross-experiment analysis in world-class male players (ATP/ITF, n = 10) revealed that the timing of initial foot movement was significantly correlated with the leg stiffness (r² = 0.54), with later lateral step after the serve in the players who had higher stiffness. The findings support the hypothesis that world-class tennis players adapt perceptual-motor control on the basis of their neuromechanical capabilities and maximise the time before initiating their interceptive action to rely on more reliable information.

Heat stress does not exacerbate tennis-induced alterations in physical performance

Objectives

To assess the time course of changes in physical performance in response to match-play tennis under heat stress.

Methods

Two matches consisting of 20 min of effective playing time (2×10 min segments) were played in COOL (∼102 min; ∼22°C and 70% relative humidity (RH)) and HOT (∼119 min; ∼36°C and 35% RH) environments. Repeated-sprint ability (3×15 m, 15 s rest), 15 m sprint time with a direction change (180°), vertical jump height (squat and countermovement jumps) and leg stiffness (multirebound jumps) were assessed in 12 competitive male players prematch, midmatch and postmatch, and 24 and 48 h after match completion.

Results

During the repeated-sprint ability test, initial (+2.3% and +3.1%) and cumulated sprint (+1.5% and +2.8%) times increased from prematch to midmatch and postmatch, respectively (p<0.001), while the sprint decrement score did not change. Match-play tennis induced a slowing (average of both conditions: +1.1% and +1.3% at midmatch and postmatch time points; p=0.05) of 15 m sprint time with direction change. Compared with prematch, leg stiffness (−6.4% and −6.5%; p<0.001) and squat jump height (−1.5% and −2.4%; p=0.05), but not countermovement jump height (−0.7% and −1.3%; p>0.05), decreased midmatch and postmatch, respectively, regardless of the condition. Complete recovery in all physical performance markers occurred within 24 h.

Conclusions

In tennis, match-related fatigue is characterised by impaired repeated-sprint ability, explosive power and leg stiffness at midmatch and postmatch, with values restored to prematch baseline 24 h into recovery. In addition, physical performance responses (match and recovery kinetics) are identical when competing in cool and hot environments.