Changes in Duration and Intensity of the World's Top-Level Badminton Matches: A Consideration of the Increased Acute Injuries among Elite Women's Singles Players

Difference in badminton-specific endurance evaluated by a newly developed on-court test between competitive levels: A pilot study of female players

We developed a test to evaluate badminton-specific endurance. The study included 10 female badminton players. Five participants were ranked in Japan's top 100 national rankings (ranked), whereas the others were unranked (unranked). Participants reacted quickly with badminton-specific steps from the base center to the four sensors at each corner of a singles badminton court. On each set, they reacted eight times to randomized instructions at stage-specific intervals (1.2, 1.0, and 0.8 s for stages 1, 2, and 3, respectively), which were performed six times with a rest of 20 s in each stage (8 movements × 6 sets × 3 stages). On a different day, participants ran on a treadmill as a comparative test. Blood lactate concentration (BLa) was measured on each test. In the badminton-specific test, ranked participants had lower BLa (4.2 ± 1.7 mM vs. 6.3 ± 3.1 mM), with medium or large effect sizes. The average reach time to sensors was shorter in ranked participants (1.56 ± 0.03 s vs. 1.62 ± 0.07 s), with medium or large effect sizes. BLa was similar between groups, with trivial or small effect sizes in the running test. These results suggest that the newly developed test can evaluate badminton-specific endurance.

Shoulder muscle imbalance as a risk factor for shoulder injury in elite badminton players: A prospective study

OBJECTIVES

To assess the impact of preseason shoulder testing on the risk of significant shoulder injury (SSI) in elite badminton players.

DESIGN

Prospective cohort study.

SETTING

Secondary care, academic medical center.

PARTICIPANTS

Nineteen elite badminton players (19.37 ± 4.79 years, n = 13 males).

MAIN OUTCOME MEASURES

At preseason, they had shoulder examination tests including the table-to-acromion distance and the glenohumeral rotation range of motion. The glenohumeral internal rotation deficit (GIRD) was calculated. Isokinetic internal and external rotator shoulder muscle strength was tested at 60°/s (concentric and eccentric modes) and 240°/s (concentric mode). Bilateral strength ratio (non-dominant:dominant) and unilateral agonist:antagonist conventional and functional ratios (FR: eccentric-to-concentric) were calculated.

RESULTS

During the follow-up time of 38 weeks, SSIs were assessed by an experienced sport physician and 42% of the participants sustained at least one SSI at their dominant side. The preseason GIRD and FR at 240°/s (FR₂₄₀) were independently associated with SSIs (G² = 6.28, p = .012 and G² = 6.23, p = .013, respectively). FR₂₄₀ < 0.69 (odds ratio = 28.0) and GIRD> 14° (odds ratio = 36.14) were predictors for SSIs.

CONCLUSIONS

Lower functional deceleration ratio and greater GIRD are associated with a higher risk of SSI at the dominant side in elite badminton players.

Notational Analysis and Physiological and Metabolic Responses of Male Junior Badminton Match Play

We examined the game characteristics of badminton and the physiological and metabolic responses in highly trained male junior players. Players from a Badminton England accredited Performance Centre (n = 10, age: 14.0 ± 1.2 y, height: 1.69 ± 0.06 m, body mass: 59.1 ± 5.0 kg) completed a 20-m shuttle run test (V˙O_2max: 64 ± 7 mL·kg^-1·min^-1) and a simulated ability-matched competitive singles badminton game consisting of two 12-min games with a 2-min break wearing the COSMED K5 metabolic system with notational analysis. In five games, 427 points were contested with a rally time of 5.7 ± 3.7 s, a rest time of 11.2 ± 5.9 s, shots per rally of 5.6 ± 3.6, work density of 0.50 ± 0.21, an effective playing time of 32.3 ± 8.4%, and shots frequency of 1.04 ± 0.29. During badminton play, heart rate was 151 ± 12 b·min^-1 (82 ± 10% of maximum heart rate), oxygen uptake was 39.2 ± 3.9 mL·kg^-1·min^-1 (62 ± 7% of V˙O_2max), and energy expenditure was 11.2 ± 1.1 kcal·min^-1 with a post-game blood lactate of 3.33 ± 0.83 mmol·L^-1. Compared to adult badminton play, the physiological responses of junior badminton are lower and may be due to the shorter rally durations. Male junior badminton players should be exposed to training methodologies which include rally durations in excess of what they encounter during match play so as to develop greater consistency. Our observations on game characteristics and physiological responses during junior badminton can be used to inform training practice.

Data Collection Procedures and Injury Definitions in Badminton: A Consensus Statement According to the Delphi Approach

ABSTRACT

Previous studies involving injury surveillance in badminton players have used nonstandardized injury definitions and data collection methodologies. The purpose of this study was to apply a Delphi method to (1) reach a consensus on an injury definition in badminton and (2) develop a standardized badminton injury report form. An Injury Consensus Group was established under the auspices of the Badminton World Federation, and initial injury definitions and injury report form were developed. An internal panel was formed from the Injury Consensus Group, and an external panel was selected based on a combination of profession, experience in the field, sport-specific knowledge/expertise, and geographical location to obtain a widely representative sample. Through 2 rounds of voting by the external panel, consensus was reached on both the definition of an injury in badminton and a standardized injury report form. The agreed injury definition was "Any physical injury sustained by a player during a match or training regardless if further diagnostic tests were done or if playing time was lost" and the injury report form contained the following 7 sections: Injury record, Diagnosis, Injury mechanism, Regarding pain, Pain and return to play/training after injury, Grade of severity, and Recurrence. We recommend the use of the definitions and methods presented in this consensus statement for the reporting of injury in all international and domestic badminton players. This should make future injury surveillance reports directly comparable and hence more informative in recognizing trends over time and differences between countries.

Training and injuries among world elite junior badminton players - Identifying the problems

Background

The game of badminton has evolved since the early injury epidemiology studies. Since there is no published literature on injuries in elite junior badminton players from an international cohort, this study provides an updated reference of injuries in this population to inform future injury prevention strategies. The objective of this study was to report injury prevalence and training hours in elite junior badminton players participating at the World Junior Championships in 2018.

Methods

A questionnaire was used to collect data and was available in English, French, Spanish, Korean, Japanese or Chinese. It was designed to collect information including basic demographics, hours of training and competition, number of tournaments per year, current and previous injuries characterized by anatomical region, diagnosis, treatment and injury duration. The questions were focused on previous significant injuries lasting a minimum of 30 days and current musculoskeletal symptoms.

Results

One hundred and sixty-four of 436 players with a mean age of 17.1 years (SD ± 0.8) filled in the questionnaire. Participants represented North and South America, Europe, Asia, Africa and The Pacific's including the top 10 performing nations, providing a good overall representation of tournament participants. A total of 104 significant injuries (median duration of 90 days) with disruption of full training or competition capacity were reported. Seventy-eight (48%) players reported one or more significant injury. The most common location of significant injury was in the knee, ankle and lower back. Eleven injuries were reported as stress fractures. In 35 cases a player felt lasting limitation from a significant injury and in 37 cases a player felt lasting pain.

Conclusion

Previously in their career almost 50% of the players had sustained a significant injury with a median duration of 90 days. The lower extremities and the lower back were the predominant injured regions. In one third of the injuries a player had lasting limitations or pain. Stress fractures may be a serious underestimated problem in badminton.

Morning Heart Rate Variability as an Indication of Fatigue Status in Badminton Players during a Training Camp

This study aimed to clarify whether changes in the fatigue status of elite athletes during a precompetition period could be evaluated using morning heart rate variability (HRV) indices. Eight Japanese National Badminton Team players (age, 23.0 ± 2.8 years) participated in this study. HRV and subjective fatigue were measured during the first (days 1–4: Phase 1) and the second half (days 5–8: Phase 2) of an 8-day national team training camp. The global and parasympathetic HRV indices were as follows: standard deviation of all R-R intervals (SDNN) (Phase 1, 87.5 ms; Phase 2, 104.3 ms; p < 0.05), root mean square of the successive R-R interval differences (RMSSD) (Phase 1, 66.6 ms; Phase 2, 103.6 ms; p < 0.05), and high-frequency component power (HF) (Phase 1, 1412.0 ms²; Phase 2, 3318.5 ms²; p < 0.05). All the aforementioned indices increased significantly from Phase 1 to Phase 2. Significant correlations were observed between the change in subjective fatigue and changes in SDNN, RMSSD, and HF (ρ = −0.80, p = 0.017; ρ = −0.77, p = 0.027; and ρ = −0.80, p = 0.017, respectively). Measuring morning HRV indices may be effective for objectively evaluating changes in the fatigue status of elite athletes during a precompetition period.

Effect of Scaling Task Constraints on the Learning Processes of Under-11 Badminton Players during Match-Play

Scaling equipment and the playing space according to junior badminton players’ characteristics and needs is a key aspect to design optimal learning environments. The purpose of the study is to analyze the incidence of reducing the court size (from 13.40 m × 5.18 m to 11.88 m × 5.18 m) and net height (from 1.55 m to 1.30 m) for under-11 badminton players on the following technical and tactical variables: (a) service area; (b) stroke effectiveness; (c) kinds of technical strokes; (d) players’ hitting area; (e) shuttle landing area; (f) shuttle flight; and (g) rally length. Twenty-eight badminton players (mean age of players: 9.81 ± 0.93) were selected and played a badminton competition (B) with the current federative rules and a mini-badminton competition (MB) with the altered net height and court dimensions. The results showed that a lower net height and a shorter court would increase the frequency and variability of strokes and play patterns, introducing quantifiable changes considered beneficial for children in their first stages, both in training and competition.