Tennis Physiology

Heart rate deflection point relates to second ventilatory threshold in a tennis test

The relationship between heart rate deflection point (HRDP) and the second ventilatory threshold (VT2) has been studied in continuous sports, but never in a tennis-specific test. The aim of the study was to assess the relationships between HRDP and the VT2, and between the maximal test performance and the maximal oxygen uptake ((Equation is included in full-text article.)) in an on-court specific endurance tennis test. Thirty-five high-level tennis players performed a progressive tennis-specific field test to exhaustion to determine HRDP, VT2, and (Equation is included in full-text article.). Ventilatory gas exchange parameters were continuously recorded by a portable telemetric breath-by-breath gas exchange measurement system. Heart rate deflection point was identified at the point at which the slope values of the linear portion of the time/heart rate (HR) relationship began to decline and was successfully determined in 91.4% of the players. High correlations (r = 0.79-0.96; p < 0.001) between physiological (HR and oxygen uptake [(Equation is included in full-text article.)]) and performance (Time, Stage, and Frequency of balls [Ballf]) variables corresponding to HRDP and VT2 were observed. Frequency of balls at the HRDP (BallfHRDP) was detected at 19.8 ± 1.7 shots per minute. Paired t-test showed no significant differences in HR (178.9 ± 8.5 vs. 177.9 ± 8.7 b·min for HRDP vs. HRVT2, respectively) at intensities corresponding to HRDP and VT2. Maximal test performance and (Equation is included in full-text article.)were moderately correlated (r = 0.56; p < 0.001). Heart rate deflection point obtained from this specific tennis test can be used to determine the VT2, and the BallfHRDP can be used as a practical performance variable to prescribe on-court specific aerobic training at or near VT2.

Enhancing physical performance in elite junior tennis players with a caffeinated energy drink

The aim of this study was to investigate the effectiveness of a caffeinated energy drink to enhance physical performance in elite junior tennis players. In 2 different sessions separated by 1 wk, 14 young (16 ± 1 y) elite-level tennis players ingested 3 mg caffeine per kg body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed a handgrip-strength test, a maximal-velocity serving test, and an 8 × 15-m sprint test and then played a simulated singles match (best of 3 sets). Instantaneous running speed during the matches was assessed using global positioning (GPS) devices. Furthermore, the matches were videotaped and notated afterward. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased handgrip force by ~4.2% ± 7.2% (P = .03) in both hands, the running pace at high intensity (46.7 ± 28.5 vs 63.3 ± 27.7 m/h, P = .02), and the number of sprints (12.1 ± 1.7 vs 13.2 ± 1.7, P = .05) during the simulated match. There was a tendency for increased maximal running velocity during the sprint test (22.3 ± 2.0 vs 22.9 ± 2.1 km/h, P = .07) and higher percentage of points won on service with the caffeinated energy drink (49.7% ± 9.8% vs 56.4% ± 10.0%, P = .07) in comparison with the placebo drink. The energy drink did not improve ball velocity during the serving test (42.6 ± 4.8 vs 42.7 ± 5.0 m/s, P = .49). The preexercise ingestion of caffeinated energy drinks was effective to enhance some aspects of physical performance of elite junior tennis players.

Grunting in tennis increases ball velocity but not oxygen cost

Grunting is widely used by professional tennis players, but no research has been done to verify enhanced performance with grunting. Therefore, the purpose of this study was to determine if grunting enhanced ball velocity in groundstrokes and secondly, to determine if grunting increased the physiological cost of hitting (VO2, HR, VE/VO2, and RPE). Participants were 10 members of the men's (n = 5) and women's (n = 5) tennis teams at a Division I university who had just completed their indoor competitive season. Two hitting sessions were used as players repetitively hit forehand and backhand shots while either grunting or not grunting. Each hitting session consisted of five 2-minute periods with a 1-minute break in between each period. Ball velocity was measured with a radar gun. During each hitting session, players wore a portable metabolic measuring unit. HR was monitored using a Polar monitor, and RPE was assessed using Borg's 6-20 scale. Grunting increased ball velocity (kph) 3.8% compared with non-grunting condition (p < 0.034) with the mean ± SD being 83.4 ± 0.6.1 and 80.3 ± 0.8.7, respectively. The physiological responses (VO2, HR, VE/VO2, and RPE) for the 2 hitting conditions were not significantly different for any variable. When averaged across both hitting conditions, HR over the 5-time periods was higher in periods 3-5 than period (p < 0.018) 1, whereas VE/VO2 and RPE were greater in periods 2-5 than period 1 (p = 0.001). RPE significantly increased over time with periods 2-5 being greater than period 1 (p = 0.001). It was concluded that grunting increased ball velocity without increasing VO2 or VE/VO2 or RPE in comparison with not grunting. It may be worthwhile for players and coaches in tennis and other sports to experiment with grunting to determine possible improvement in performance.

Tennis for physical health: acute age- and gender-based physiological responses to cardio tennis

This study described physiological and perceptual responses to Cardio tennis for "younger" and "older" adult populations of both sexes for health-related outcomes. Thirty-one active participants, each with prior recreational tennis experience (∼2 years) (8 younger and 8 older males, and 7 younger and 8 older females) performed preliminary testing and a 50-minute instructor-led Cardio tennis session. Cardio tennis is a conditioning-based tennis program comprised of warm-up movements, drill-based exercises (set movement and hitting games), and competitive play scenarios. Participants performed the 20-m shuttle run test to determine maximal heart rate (HR) during preliminary testing. Before, after, and 30-minute post Cardio tennis session, HR, blood pressure (BP), rate pressure product (RPP), and capillary blood lactate and glucose were determined. Furthermore, HR and pedometer-derived step counts were measured throughout, while the session was filmed and coded for technical skill. After the session, ratings of perceived exertion, enjoyment, and challenge were obtained. Heart rate, systolic BP, and RPP were significantly increased by Cardio tennis (p ≤ 0.05), though returned to pre-exercise levels after 30 minutes (p > 0.05). Heart rate and BP did not differ between groups pre- or 30-minute postexercise (p > 0.05); however, these were lower in younger males during and higher in younger females postsession (p ≤ 0.05). Lactate and glucose concentrations were increased in all groups (p ≤ 0.05), with lactate being highest in male groups (p ≤ 0.05), without differences in glucose between groups (p > 0.05). Stroke and step counts were not different between groups (p > 0.05). Ratings of perceived exertion and perceived challenge were lowest in the younger male group compared with all other groups (p ≤ 0.05). Cardio tennis presents as an effective stimulus to invoke sufficient cardiovascular and metabolic load to benefit health and fitness, though age- and sex-based responses should be considered in prescription.

Fitness testing of tennis players: how valuable is it?

In tennis, sport-specific technical skills are predominant factors, although a complex profile of physical performance factors is also required. The fitness test batteries assist in examining tennis players' capabilities for performance at different levels in the laboratory as well as in the field, in the junior or elite level. While laboratory tests can be, and are, used to evaluate basic performance characteristics of athletes in most individual sports, in a more specific approach, field-based methods are better suited to the demands of complex intermittent sports like tennis. A regular test battery performed at different periods of the year allows to obtain an individual's performance profile, as well as the ability to prescribe individual training interventions. Thus, the aim of the present review was to describe and evaluate the different physical tests recommended and used by practitioners, sports scientists and institutions (national tennis federations).

Physiological, perceptual, and technical responses to on-court tennis training on hard and clay courts

The aim of this study was to investigate the effect of court surface (clay vs. hard court) on technical, physiological, and perceptual responses to on-court tennis training. Four high-performance junior male players performed 2 identical training sessions on hard and clay courts, respectively. Sessions included both physical conditioning and technical elements as led by the coach. Each session was filmed for later notational analysis of stroke count and error rates. Furthermore, players wore a global positioning satellite device to measure distance covered during each session, while heart rate, countermovement jump distance, and capillary blood measures of metabolites were measured before, during, and after each session. Additionally, a respective coach and athlete rating of perceived exertion (RPE) were measured after each session. Total duration and distance covered during each session were comparable (p > 0.05; d < 0.20). Although forehand and backhands stroke volume did not differ between sessions (p > 0.05; d < 0.30), large effects for increased unforced and forced errors were present on the hard court (p > 0.05; d > 0.90). Furthermore, large effects for increased heart rate, blood lactate, and RPE values were evident on clay compared with hard courts (p > 0.05; d > 0.90). Additionally, although player and coach RPE on hard courts were similar, there were large effects for coaches to underrate the RPE of players on clay courts (p > 0.05; d > 0.90). In conclusion, training on clay courts results in trends for increased heart rate, lactate, and RPE values, suggesting that sessions on clay courts tend towards higher physiological and perceptual loads than hard courts. Furthermore, coaches seem effective at rating player RPE on hard courts but may underrate the perceived exertion of sessions on clay courts.

Muscle damage after a tennis match in young players

The present study investigated changes in indirect markers of muscle damage following a simulated tennis match play using nationally ranked young (17.6 ± 1.4 years) male tennis players. Ten young athletes played a 3-hour simulated match play on outdoor red clay courts following the International Tennis Federation rules. Muscle soreness, plasma creatine kinase activity (CK), serum myoglobin concentration (Mb), one repetition maximum (1RM) squat strength, and squat jump (SJ) and counter movement jump (CMJ) heights were assessed before, immediately after, and 24 and 48 h after the simulated match play. All parameters were also evaluated in a non-exercised group (control group). A small increase in the indirect markers of muscle damage (muscle soreness, CK and Mb) was detected at 24-48 hours post-match (p < 0.05). A marked acute decrement in neuromuscular performance (1RM squat strength: -35.2 ± 10.4%, SJ: -7.0 ± 6.0%, CMJ: -10.0 ± 6.3%) was observed immediately post-match (p < 0.05). At 24 h post-match, the 1RM strength and jump heights were not significantly different from the baseline values. However, several players showed a decrease of these measures at 24 h after the match play. The simulated tennis match play induced mild muscle damage in young players. Coaches could monitor changes in the indirect markers of muscle damage to assess athletes’ recovery status during training and competition.

Criterion validity and accuracy of global positioning satellite and data logging devices for wheelchair tennis court movement

PURPOSE

To compare the criterion validity and accuracy of a 1 Hz non-differential global positioning system (GPS) and data logger device (DL) for the measurement of wheelchair tennis court movement variables.

METHODS

Initial validation of the DL device was performed. GPS and DL were fitted to the wheelchair and used to record distance (m) and speed (m/second) during (a) tennis field (b) linear track, and (c) match-play test scenarios. Fifteen participants were monitored at the Wheelchair British Tennis Open.

RESULTS

Data logging validation showed underestimations for distance in right (DLR) and left (DLL) logging devices at speeds >2.5 m/second. In tennis-field tests, GPS underestimated distance in five drills. DLL was lower than both (a) criterion and (b) DLR in drills moving forward. Reversing drill direction showed that DLR was lower than (a) criterion and (b) DLL. GPS values for distance and average speed for match play were significantly lower than equivalent values obtained by DL (distance: 2816 (844) vs. 3952 (1109) m, P = 0.0001; average speed: 0.7 (0.2) vs. 1.0 (0.2) m/second, P = 0.0001). Higher peak speeds were observed in DL (3.4 (0.4) vs. 3.1 (0.5) m/second, P = 0.004) during tennis match play.

CONCLUSIONS

Sampling frequencies of 1 Hz are too low to accurately measure distance and speed during wheelchair tennis. GPS units with a higher sampling rate should be advocated in further studies. Modifications to existing DL devices may be required to increase measurement precision. Further research into the validity of movement devices during match play will further inform the demands and movement patterns associated with wheelchair tennis.

Wheelchair tennis match-play demands: effect of player rank and result

PURPOSE

To examine the heart-rate (HR) response and court-movement variables during wheelchair tennis match play for high- (HIGH) and low- (LOW) performance-ranked players. Analysis of physiological and movement-based responses during match play offers an insight into the demands of tennis, allowing practical recommendations to be made.

METHODS

Fourteen male open-class players were monitored during tournament match play. A data logger was used to record distance and speed. HR was recorded during match play.

RESULTS

Significant rank-by-result interactions revealed that HIGH winners covered more forward distance than HIGH losers (P < .05) and had higher average (P < .05) and minimum (P < .01) HRs than LOW winners. LOW losers had higher average (P < .01) and minimum (P < .001) HRs than LOW winners. Independent of result, a significant main effect for rank was identified for maximum (P < .001) and average (P < .001) speed and total (P < .001), reverse (P < .001), and forward-to-reverse (P < .001) distance, with higher values for HIGH. Independent of rank, losing players experienced higher minimum HRs (P < .05). Main effects for maximum HR and actual playing time were not significant. Average playing time was 52.0 (9.1) min.

CONCLUSIONS

These data suggest that independent of rank, tennis players were active for sufficient time to confer health-enhancing effects. While the relative playing intensity is similar, HIGH players push faster and farther than LOW players. HIGH players are therefore more capable of responding to ball movement and the challenges of competitive match play. Adjustments to the sport may be required to encourage skill developmental in LOW players, who move at significantly lower speeds and cover less distance.

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

The aim of this study was to compare the effects of high-intensity interval training (HIIT) and repeated-sprint training (RST) on aerobic fitness, tennis-specific endurance, linear and repeated-sprint ability (RSA), and jumping ability. Thirty-one competitive male tennis players took part in a training intervention of 6 weeks. The players were matched into 3 groups, HIIT (n = 11), RST (n = 12), or control group (CON, n = 9). The results showed significant time × intervention interactions for VO(2)peak, with a significant increase in the VO(2)peak level of 6.0% in HIIT (p = 0.008) and 4.9% in RST (p = 0.010), whereas no changes occurred in CON. However, the following differences were found between the intervention groups: The HIIT-induced greater improvements in tennis-specific endurance (HIIT 28.9% vs. RST 14.5%; p < 0.05) and RST led to a significant improvement in RSA (i.e., reduction in the mean sprint time of 3.8%; p < 0.05). Neither training strategy induced any effects on jumping and sprinting abilities. Both training interventions showed similar improvements in general aerobic fitness. Also, the present results suggest that RST represents a time-efficient stimulus for a simultaneous improvement of general and tennis-specific aerobic fitness as well for RSA.

A six-week neuromuscular training program for competitive junior tennis players

This study evaluated the effectiveness of a tennis-specific training program on improving neuromuscular indices in competitive junior players. Tennis is a demanding sport because it requires speed, agility, explosive power, and aerobic conditioning along with the ability to react and anticipate quickly, and there are limited studies that evaluate these indices in young players after a multiweek training program. The program designed for this study implemented the essential components of a previously published neuromuscular training program and also included exercises designed to improve dynamic balance, agility, speed, and strength. Fifteen junior tennis players (10 girls, 5 boys; mean age, 13.0 +/- 1.5 years) who routinely participated in local tournaments and high-school teams participated in the 6-week supervised program. Training was conducted 3 times a week, with sessions lasting 1.5 hours that included a dynamic warm-up, plyometric and jump training, strength training (lower extremity, upper extremity, core), tennis-specific drills, and flexibility. After training, statistically significant improvements and large-to-moderate effect sizes were found in the single-leg triple crossover hop for both legs (p < 0.05), the baseline forehand (p = 0.006) and backhand (p = 0.0008) tests, the service line (p = 0.0009) test, the 1-court suicide (p < 0.0001), the 2-court suicide (p = 0.02), and the abdominal endurance test (p = 0.01). Mean improvements between pretrain and posttrain test sessions were 15% for the single-leg triple crossover hop, 10-11% for the baseline tests, 18% for the service line test, 21% for the 1-court suicide, 10% for the 2-court suicide, and 76% for the abdominal endurance test. No athlete sustained an injury or developed an overuse syndrome as a result of the training program. The results demonstrate that this program is feasible, low in cost, and appears to be effective in improving the majority of neuromuscular indices tested. We accomplished our goal of developing training and testing procedures that could all be performed on the tennis court.

A comparison of the physiological demands of wheelchair basketball and wheelchair tennis

PURPOSE

To examine the physiological profiles of wheelchair basketball and tennis and specifically to: (a) identify if there are differences in the physiological profiles of wheelchair basketball and tennis players of a similar playing standard, (b) to determine whether the competitive physiological demands of these sports differed (c) and to explore the relationship between the blood lactate [Bla-] response to exercise and to identify the sport specific heart rate (HR) training zones.

METHODS

Six elite athletes (4 male, 2 female) from each sport performed a submaximal and VO2peak test in their sport specific wheelchair. Heart rate, VO2, and [Bla-] were measured. Heart rate was monitored during international competitions and VO2 was calculated from this using linear regression equations. Individual HR training zones were identified from the [Bla-] profile and time spent within these zones was calculated for each match.

RESULTS

Despite no differences in the laboratory assessment of HRpeak, the VO2peak was higher for the basketball players when compared with the tennis players (2.98 ± 0.91 vs 2.06 ± 0.71; P = .08). Average match HR (163 ± 11 vs 146 ± 16 beats x min(-1); P = .06) and average VO2 (2.26 ± 0.06 vs 1.36 ± 0.42 L x min(-1); P = .02) were higher during actual playing time of basketball when compared with whole tennis play. Consequently, differences in the time spent in the different training zones within and between the two sports existed (P < .05).

CONCLUSIONS

Wheelchair basketball requires predominately high-intensity training, whereas tennis training requires training across the exercise intensity spectrum.

Physiological responses and characteristics of table tennis matches determined in official tournaments

The purpose of this study was to verify the physiological responses and the match characteristics of table tennis and also to compare these responses in 2 different performance-level athletes from official tournaments. Twenty male table tennis players (12 regional experience-RP and 8 national and international experience-NP) were participants in the study. Blood lactate concentration ([LAC]) and heart rate (HR) were measured as physiological parameters in 21 official table tennis matches, and other 12 matches had recorded the duration of rally (DR), rest time, effort and rest ratio (E:R), total playing time (TPT), effective playing time (EPT), and frequency of shots by video analyses. The [LAC] verified in all matches was 1.8 mmol.L (+/-0.8), whereas the [LAC] peak was 2.2 mmol.L (+/-0.8). There were no significant differences between the 2 groups (p > 0.05) in both parameters. The HR was 164 b.min (+/-14), corresponding to 81.2% (+/-7.4) of the predicted maximum HR. As characteristics of the matches, the DR corresponded to 3.4 seconds (+/-1.7), rest time to 8.1 seconds (+/-5.1), E:R to 0.4 (+/-0.2), TPT to 970.5 seconds (+/-336.1), EPT to 44.3% (+/-23.7), and frequency of shots to 35.3 balls.min (+/-7.7). Among groups, the rest time was lower in RP than in NP. Consistently, the E:R and EPT were higher in RP than in NP (p < 0.05). The results suggest that table tennis matches present the aerobic system as a principal output energy, the phosphagenic system being the most important during efforts. The information pertaining to the physiological profile and the characteristics of table tennis should be used by coaches planning physical training and specific exercise prescriptions aiming at achieving maximal sport performance.

A review of fluid and hydration in competitive tennis

Hypohydration is known to impair performance and increases the risk of heat injury. Therefore, the consumption of appropriate fluid volumes before, during, and after tennis play is important to maintain physiological homeostasis and performance. Tennis is a sport that typically has points lasting fewer than ten seconds, with short-to-moderate rest periods between each work bout. This sequence is repeated over hours. Most fluid and hydration research has focused on continuous aerobic exercise, which provides vastly different physiological strain compared with tennis practice and competition. Consequently, practical recommendations on maintaining hydration status for aerobic continuous exercise may not be appropriate for tennis athletes. Tennis players can sweat more than 2.5 L.h(-1) and replace fluids at a slower rate during competition than in practice. In warm and hot environments, electrolyte-enhanced fluid should be consumed at greater than >200 mL per changeover and ideally closer to 400 mL per changeover. Tennis scientists, coaches, and players need to individualize hydration protocols to arrive at the optimal hydration strategy.

Exercise-induced homeostatic perturbations provoked by singles tennis match play with reference to development of fatigue

This review addresses metabolic, neural, mechanical and thermal alterations during tennis match play with special focus on associations with fatigue. Several studies have provided a link between fatigue and the impairment of tennis skills proficiency. A tennis player's ability to maintain skilled on-court performance and/or optimal muscle function during a demanding match can be compromised as a result of several homeostatic perturbations, for example hypoglycaemia, muscle damage and hyperthermia. Accordingly, an important physiological requirement to succeed at competitive level might be the player's ability to resist fatigue. However, research evidence on this topic is limited and it is unclear to what extent players experience fatigue during high-level tennis match play and what the physiological mechanisms are that are likely to contribute to the deterioration in performance.

Physical performance changes after unsupervised training during the autumn/spring semester break in competitive tennis players

BACKGROUND

All competitive tennis players take time away from coaches throughout the year; however, little information is available as to the short-term physiological effect of these breaks.

OBJECTIVE

The purpose of this investigation was to evaluate the impact of a 5 week off-campus structured, yet unsupervised, break from regular training in top collegiate tennis players.

METHODS

A nationally ranked collegiate NCAA Division I male tennis team (n = 8) performed a test battery in December and again in January after a 5 week period of recommended, yet unsupervised, training. The tests performed were 5, 10 and 20 m sprints, spider agility test, medicine ball power throws, standing long jump, Wingate anaerobic power test, VO2max, push-up and sit-up test, grip strength and range of motion (ROM) measures (goniometer) of the shoulder, hip, hamstring and quadriceps.

RESULTS

Paired t tests (p<0.05) showed significant decreases in mean (SEM) Wingate power measurements in Watts/kg (pre: 8.35 (0.19) w/kg ; post: 7.80 (0.24) w/kg ), minimum Wingate power (pre: 5.89 (0.27) w/kg; post: 5.10 (0.38) w/kg) and VO2max values (pre: 53.90 (1.11) ml/kg/min; post: 47.86 (1.54) ml/kg/min). A significant increase was seen in the athlete's fatigue index (pre: 44.26 (2.85)%; post: 51.41 (3.53)%), fastest 5 m (pre: 1.07 (0.03) s; post: 1.12 (0.02) s), 10 m (pre: 1.79 (0.03) s; post: 1.84 (0.04) s) and 20 m (pre: 3.07 (0.05) s; post: 3.13 (0.05) s) sprint times. No significant differences were seen for the other variables tested.

CONCLUSIONS

These results suggest that a 5 week interruption of normal training can result in significant reductions in speed, power and aerobic capacity in competitive tennis players, likely owing to poor compliance with the prescribed training regimen. Therefore, coaches and trainers might benefit from techniques (eg, pre- and post-testing) requiring athletes' to have accountability for unsupervised workouts.