Effects of consecutive days of match play on technical performance in tennis

Dietary Intake and Daily Distribution of Carbohydrate, Protein and Fat in Youth Tennis Players over a 7-Day Training and Competition Period

During a 7-day training and/or competition period, macronutrient intake and distribution was assessed using food diaries, supported by remote food photography and 24-hr multiple pass recalls of youth tennis players categorised by under 12s, under 14s and under 16+ age groups (n = 27). Total energy did not differ between age groups nor type of day (training [TD], competition day [CD]), irrespective of a significant increase in body mass reported in the older players (U16+; p < 0.05). Average intakes were consistently below 2250 kcal·day-1 (range 1965 ± 317-2232 ± 612 kcal·day-1). Carbohydrate consumption was below guidelines for all groups (≤6g·kg-1). Conversely, protein intake met or exceeded guidelines throughout, with intakes ≥2 g·kg-1 for both the U12 and U14 age groups on both days. Protein intake was ~17% higher on TDs than CDs (p < 0.05), with protein intake at lunch significantly higher on TDs than CDs (p < 0.05). No further differences were observed between breakfast, lunch or dinner between group or day. Inconsistent snacking was reported, with players consuming snacks on less than half of the days reported (46 ± 12% of TDs and 43 ± 30% of CDs). In conclusion, youth tennis players present sub-optimal nutrition practices, appearing to under fuel and under consume carbohydrate for performance, adaptation, recovery and health.

A Combined Sleep Hygiene and Mindfulness Intervention to Improve Sleep and Well-Being During High-Performance Youth Tennis Tournaments

PURPOSE

To investigate the effects of combined sleep hygiene recommendations and mindfulness on actigraphy-based sleep parameters, perceptual well-being, anxiety, and match outcomes during high-performance junior tennis tournaments.

METHODS

In a randomized crossover design, 17 high-performance junior tennis players completed the baseline, control, and intervention (INT) conditions across 3 separate weeks. The baseline consisted of unassisted, habitual sleep during a regular training week, and the control was unassisted sleep during a tournament week. The players attended a sleep education workshop and completed a nightly sleep hygiene protocol during a tournament week for the INT. Analysis was performed on the weekly means and on the night prior to the first match of the tournament (T-1).

RESULTS

Significant differences were observed for increased time in bed, total sleep time, and an earlier bedtime (P < .05) across the INT week. These parameters also significantly improved on T-1 of the INT. A moderate effect size (P > .05, d > 1.00) was evident for decreased worry on T-1 of the INT. Small effect sizes were also evident for improved mood, cognitive anxiety, and sleep rating across the INT week. The match performance outcomes remained unchanged (P > .05).

CONCLUSIONS

Sleep hygiene INTs increase the sleep duration of high-performance junior tennis players in tournament settings, including the night prior to the tournament's first match. The effects on perceptual well-being and anxiety are unclear, although small trends suggest improved mood, despite no effect on generic match performance outcomes.

Developmental fitness curves: assessing sprint acceleration relative to age and maturity status in elite junior tennis players

BACKGROUND

The influence of maturity-status on athletic performance is reasonably well-documented. Methodological and practical issues of assessment and lack of longitudinal data have impacted the success of various models.

AIM

To develop age- and sex-specific developmental curves for sprint acceleration in elite youth tennis players and to address variation in performance relative to chronological and biological age.

SUBJECTS AND METHODS

Measures of acceleration were available for 3120 elite youth tennis players aged 8-15 years attending National and Regional Talent Identification days. Variation in acceleration by chronological and estimated biological ages was evaluated in corresponding data for an independent sample of elite youth players 8.9 to 15.1 years of age.

RESULTS

Acceleration varied as a function of chronological and biological age relative to developmental curves. Early maturing males and females had significantly poorer performances when acceleration was considered relative to biological age. Significant discrepancy in percentiles relative to biological versus chronological ages was also evident between early and late maturing players of each sex.

CONCLUSION

Evaluating performance relative to developmental curves and maturity status may be a practical means of monitoring long-term athlete development in tennis.

Set-to-set Performance Variation in Tennis Grand Slams: Play with Consistency and Risks

The study analysed the set-to-set variation in performance using match statistics of 146 completed main-draw matches in Australian Open and US Open 2016-2017 men’s singles. Comparisons of technical-tactical and physical performance variables were done between different sets; and the within-match coefficients of variation (CV) of these variables were contrasted between match winning and losing players. All comparisons were realized via standardized (Cohen’s d) mean differences and uncertainty in the true differences was assessed using non-clinical magnitude-based inferences. Results showed that there was possibly to very likely decreases in the serve, net and running related variables (mean difference, ±90%CL: -0.16, ±0.14 to -0.45, ±0.24, small) and an increase in the return and winner related variables (0.17, ±0.24 to 0.24, ±0.14, small) in the last sets when compared to the initial sets, indicating the influence of match fatigue and the player’s choice of match tactics and pacing strategy. Besides, winning players were revealed to have lower CV values in most of performance variables (-0.16, ±0.24 to -0.82, ±0.23, small to moderate) except for the second serve, winner, and physical performance variables (0.25, ±0.26 to 1.6, ±0.25, small to large), indicating that they would sacrifice the consistency to gain more aggressiveness and to dominate the match.

Game Activity and Physiological Responses of Young Tennis Players in a Competition With 2 Consecutive Matches in a Day

Purpose: To determine whether the game activity and physiological responses of young tennis players differed depending on the session of play (eg, morning [MOR] vs afternoon [AFT]) and the final match outcome (eg, winners vs losers) during a simulated competition with 2 matches on the same day. Methods: A total of 12 well-trained male tennis players (age 14.5 [0.8] y) took part in a simulated competition of two 3-set matches separated by 3 h. All the matches were video recorded, and the participants were monitored using 10-Hz global positioning system units including a heart-rate monitor. Effect-size (ES) statistics were used to investigate the magnitudes of the differences. Results: During the AFT matches, in absolute terms, players covered longer total distance (ES = moderate) and ran more distance between 0 and ≤4 m·s−1 (ES = small to large) than in MOR matches. Total duration was also longer (ES = large) in the AFT, where the rest time between rallies was also longer (ES = very large). Heart rate was similar during AFT and MOR matches, but higher rates of perceived exertion (ES = moderate) were reported in the AFT. Only peak running velocity was observed to be likely higher for losers than for winners (ES = small). Conclusions: Game activity and physiological responses of young tennis players differ when 2 consecutive matches are played on the same day. These data might help elucidate the need for specific precompetition training loads and/or between-matches/sessions recovery strategies when facing overloaded competitions.