Operational Insights into Analysing Team and Player Performance in Elite Rugby League: A Narrative Review with Case Examples.

In professional team sports, like Rugby League, performance analysis has become an integral part of operational practices. This has helped practitioners gain deeper insight into phenomena like team and athlete behaviour and understanding how such behaviour may be influenced by various contextual factors. This information can then be used by coaches to design representative practice tasks, inform game principles and opposition strategies, and even support team recruitment practices. At the elite level, the constant evolution of sports technology (both hardware and software) has enabled greater access to information, making the role of the performance analyst even more valuable. However, this increase in information can create challenges regarding which variables to use to help guide decision-making, and how to present it in ways that can be utilised by coaches and other support staff. While there are published works exploring aspects of performance analysis in team sports like Rugby League, there is yet to be a perspective that explores the various operational uses of performance analysis in Rugby League, the addition of which could help guide the practices of emerging performance analysts in elite organisations like the Australian National Rugby League and the European Super League. Thus, this narrative review-with accompanying case examples-explores the various ways performance analysis can help address pertinent operational questions commonly encountered when working in high-performance sport.

Cardiac Autonomic Modulation Is Associated with Arterial Stiffness in Patients with Symptomatic Peripheral Artery Disease.

BACKGROUND: The objective of this study was to analyze the association between cardiac autonomic modulation and arterial stiffness in patients with peripheral artery disease (PAD). METHODS: This cross-sectional study included one hundred fourteen patients with symptomatic PAD (67.5% men; 65 ± 7 years; body mass index: 26.8 ± 4.5 kg/m2). Heart rate variability (HRV) was measured within time (standard deviation of all RR intervals [beat to beat heart interval] [SDNN], root mean square of the successive differences between adjacent normal RR intervals [RMSSD], and the proportion of successive RR intervals that differed by more than 50 msec [pNN50]) and frequency (low frequency [LF] and high frequency [HF]) domains. Arterial stiffness was assessed by carotid-femoral pulse wave velocity (cfPWV). Crude and adjusted linear regression analyses examined the relationship between HRV and cfPWV. RESULTS: Nonsignificant crude associations were identified among cfPWV and RMSSD (P = 0.181), SDNN (P = 0.105), pNN50 (P = 0.087), LF (P = 0.376), HF (P = 0.175), and LF/HF ratio (P = 0.426). After adjustments for age, sex, smoking, body mass index, ankle-brachial index, and use of beta-blockers, significant associations were identified among cfPWV and RMSSD (P = 0.037), SDNN (P = 0.049), and pNN50 (P = 0.049). CONCLUSIONS: Cardiac autonomic modulation was significantly associated with arterial stiffness in patients with PAD after adjustment for confounding factors. This relationship may contribute to the enhanced cardiovascular disease risk for PAD patients and provides a target for strategies to improve patient clinical outcomes.

Reproducibility of heart rate recovery in patients with intermittent claudication.

BACKGROUND: Postexercise heart rate recovery (HRR) is a non-invasive tool for cardiac autonomic function assessment. Reproducibility of HRR has been established in healthy subjects; however, no study has evaluated this reproducibility in clinical populations who may present autonomic dysfunction. Patients with peripheral artery disease and intermittent claudication (IC) often present altered cardiac autonomic function and HRR could be an interesting tool for evaluating autonomic responses to interventions in this population. Therefore, the reproducibility of HRR should be determined in this specific population. OBJECTIVE: To determine the reproducibility of HRR indices in patients with IC. METHODS: Nineteen men with IC underwent two repeated maximal treadmill tests. Raw HR and relative HRR (difference to exercise peak) indices measured at 30, 60, 120, 180, 240 and 300s of recovery were evaluated. The presence of systematic bias was assessed by comparing test and retest mean values via paired t-test. Reliability was assessed by intraclass correlation coefficient (ICC), and agreement by typical error (TE), coefficient of variation (CV) and minimal detectable difference (MDD). RESULTS: There were no significant differences between the test and retest values of all raw HR and relative HRR indices (P ≥ 0·05), except for HR120s (P = 0·032). All indices exhibited excellent reliability (ICC ≥ 0·78). Raw HR and relative HRR indices showed TEs ≤ 6·4 bpm and MDDs ≤ 17·8 bpm. In addition, all indices showed CVs ≤ 13·2%, except HRR30s (CV = 45·6%). CONCLUSIONS: The current results demonstrated that most HRR indices were highly reproducible with no systematic error, excellent reliability and good agreement in patients with IC following maximal graded exercise.

Acute Inflammatory Responses to Exercise in Patients with Abdominal Aortic Aneurysm.

PURPOSE: Inflammation and extracellular matrix degeneration contribute to abdominal aortic aneurysm (AAA) development. We aimed to assess the effect of exercise intensity on circulating biomarkers of inflammation and extracellular matrix degeneration in patients with AAA and healthy older adults. METHODS: Twenty patients with AAA (74 ± 6 yr) and 20 healthy males (72 ± 5 yr) completed moderate-intensity cycling at 40% peak power output, higher-intensity intervals at 70% peak power output, and control (rest) on separate days. Circulating matrix metalloproteinase-9 (MMP-9), transforming growth factor beta 1, interleukin-6 (IL-6), IL-10, and tumor necrosis factor alpha (TNF-α) were analyzed at rest and 0 to 90 min postexercise. RESULTS: Biomarkers at baseline were similar between groups. IL-6 responses to exercise were similar between groups, with a greater increase in ΔIL-6 after moderate-intensity compared with higher-intensity exercise (P < 0.001). Delta MMP-9 showed a 118-ng·mL (95% confidence interval = 23 to 214, P = 0.02) greater increase immediately after higher-intensity exercise compared with changes in control in both groups. Delta MMP-9 then decreased by 114 ng·mL (18 to 211, P = 0.02) 90 min after higher-intensity exercise compared with the changes in control. Delta TNF-α was not different between protocols in healthy adults. In patients with AAA, delta TNF-α showed a greater decrease after higher-intensity compared with moderate-intensity exercise (-6.1 pg·mL, -8.5 to -3.6, P < 0.001) and control (-4.9 pg·mL, -7.4 to -2.4, P < 0.001). IL-10 and transforming growth factor beta 1 did not change in either group. CONCLUSIONS: These findings suggest that a bout of higher-intensity exercise elicits a greater anti-inflammatory response compared with moderate-intensity exercise, which may be further augmented in patients with AAA. Exercise-induced reductions in biomarkers associated with AAA progression may represent a protective effect of exercise in patients with AAA.

The repeated bout effect of traditional resistance exercises on running performance across 3 bouts.

This study investigated the repeated bout effect of 3 typical lower body resistance-training sessions on maximal and submaximal effort running performance. Twelve resistance-untrained men (age, 24 ± 4 years; height, 1.81 ± 0.10 m; body mass, 79.3 ± 10.9 kg; peak oxygen uptake, 48.2 ± 6.5 mL·kg-1·min-1; 6-repetition maximum squat, 71.7 ± 12.2 kg) undertook 3 bouts of resistance-training sessions at 6-repetitions maximum. Countermovement jump (CMJ), lower-body range of motion (ROM), muscle soreness, and creatine kinase (CK) were examined prior to and immediately, 24 h (T24), and 48 h (T48) after each resistance-training bout. Submaximal (i.e., below anaerobic threshold (AT)) and maximal (i.e., above AT) running performances were also conducted at T24 and T48. Most indirect muscle damage markers (i.e., CMJ, ROM, and muscle soreness) and submaximal running performance were significantly improved (P < 0.05; 1.9%) following the third resistance-training bout compared with the second bout. Whilst maximal running performance was also improved following the third bout (P < 0.05; 9.8%) compared with other bouts, the measures were still reduced by 12%-20% versus baseline. However, the increase in CK was attenuated following the second bout (P < 0.05) with no further protection following the third bout (P > 0.05). In conclusion, the initial bout induced the greatest change in CK; however, at least 2 bouts were required to produce protective effects on other indirect muscle damage markers and submaximal running performance measures. This suggests that submaximal running sessions should be avoided for at least 48 h after resistance training until the third bout, although a greater recovery period may be required for maximal running sessions.

Reproducibility of Anaerobic and Pain Thresholds in Male Patients With Intermittent Claudication.

PURPOSE: Maximal and submaximal parameters assessed during treadmill tests are used to prescribe exercise training and assess exercise-induced adaptations in patients with intermittent claudication (IC). Although reproducibility of maximal parameters is well documented, the reproducibility of submaximal is not clear. The aim of this study was to identify the reproducibility (reliability and agreement) of heart rate (HR) and oxygen uptake ((Equation is included in full-text article.)O2) measured at the anaerobic (AT) and the pain (PT) thresholds assessed during a maximal test in patients with IC. METHODS: Twenty male patients with IC underwent 2 cardiopulmonary treadmill tests to maximal pain. The HR and (Equation is included in full-text article.)O2 at the AT and PT were identified, and differences between repeat tests were compared. Reliability was determined by intraclass coefficient correlation (ICC). Agreement was assessed by coefficient of variation (CV), standard error of measurement (SEM), smallest detectable difference (SDD), and limits of agreement (LOA). RESULTS: The (Equation is included in full-text article.)O2 at AT and PT exhibited moderate reliability and moderate/good agreement (ICC = 0.73 and 0.70; CV = 9.6% and 11.1%, respectively). The HR at the AT and PT exhibited high reliability and good agreement (ICC = 0.87 and 0.92; SEM = 3.9 and 3.2 bpm; SDD = 10.8 and 8.8 bpm, respectively). The LOA for (Equation is included in full-text article.)O2 at AT and PT were ≤20% and for HR ≤11 bpm. CONCLUSIONS: The (Equation is included in full-text article.)O2 and HR measured at the AT and PT were moderately to highly reproducible in male patients with IC. The HR and (Equation is included in full-text article.)O2 at AT and PT may be used to establish training intensity and evaluate training effectiveness for these patients in clinical practice and research.

Intensity, recovery kinetics and well-being indices are not altered during an official FIFA futsal tournament in Oceanian players.

Physiological responses (intensity and recovery kinetics) and well-being indices were examined during a 4-day FIFA international tournament. Ten outfield New Caledonian players (age: 25.5 ± 3.8 years; height: 170 ± 7 cm; weight: 70.7 ± 8.6 kg) were assessed during the four matches. Players' aerobic and anaerobic capacities were measured before the tournament while heart rate (HR), intra-matches recovery and well-being indices (Hooper index) were measured throughout the tournament. HR (168 ± 8 bpm), exercise intensity (83.4 ± 2.3% of HR reserve) and recovery indices were similar throughout the tournament. Well-being indices were largely alike during the tournament while rating of perceived exertion increased throughout the tournament that was not associated with HR or well-being indices. High aerobic and anaerobic capacities were associated with high match intensities and slow recovery indices. In summary, match intensity assessed by HR, recovery kinetics and well-being of Oceanian futsal players were not modified during a 4-day FIFA futsal tournament. Assessment of aerobic and anaerobic capacities may be useful to select players for optimal performance during this type of international tournament.

Autonomic correlates of Yo-Yo performance in soccer referees / Correlatos autonômicos do desempenho no Yo-Yo em árbitros de futebol

We tested the hypothesis that: basal cardiac autonomic modulation (i.e. heart rate variability, HRV) was associated with the parasympathetic withdrawal during, and overall Yo-Yo IR1 performance; and therefore HRV could be used as a simple tool for specific fitness assessment. Nine sub-elite soccer referees performed the Yo-Yo IR1 until exhaustion with simultaneous recording of heart rate with the autonomic response during exercise calculated as the area under the curve (AUC). In the same week but with at least 48 hrs between days, a night-time HR recording was obtained from participants for determination of basal HRV. Correlation analysis demonstrated strong (r>0.83) relationships among Yo-Yo IR1 performance, AUC and basal HRV. These results indicate that both nocturnal HRV and AUC can be utilised as simple and valid monitoring tools of soccer referees' fitness.

Nós testamos a hipótese de: que a modulação autonômica cardíaca (i.e. variabilidade da freqüência cardíaca, VFC) está associada com a retirada parassimpática durante a execução do Yo-Yo IR1; e que, portanto, a VFC poderia ser usada como uma ferramenta simples para a avaliação do desempenho físico específico. Nove árbitros sub-elite de futebol executaram o Yo-Yo IR1 até a exaustão com registro simultâneo da freqüência cardíaca e VFC para o cálculo da área sob a curva (ASC). Na mesma semana, mas com mínimo de 48 horas entre dias, obteve-se um registro noturno da FC dos participantes para a determinação da VFC basal. As análises de correlação demonstraram elevados coeficientes (r>0,83) entre o desempenho no Yo-Yo IR1, a ASC e a VFC basal. Estes resultados indicam que a VFC noturna e a ASC podem ser empregadas como ferramentas simples e válidas para o monitoramento do desempenho de árbitros de futebol.

Impact of a soccer match on the cardiac autonomic control of referees.

The purpose of this study was to assess the effect of a soccer match on the cardiac autonomic control of heart rate (HR) in soccer referees. Sixteen Spanish regional and third division referees (11 males: 26 ± 7 years, 74.4 ± 4.1 kg, 178 ± 3 cm, Yo-Yo IR1 ~600-1,560 m; 5 females: 22 ± 3 years, 59.3 ± 4.8 kg, 158 ± 8 cm, Yo-Yo IR1 ~200-520 m) participated with 24-h HR recordings measured with a Polar RS800 during a rest and a match day. Autonomic control of HR was assessed from HR variability (HRV) analysis. Inclusion of a soccer match (92.5% spent at >75% maximum HR) reduced pre-match (12:00-17:00 hours; small to moderate), post-match (19:00-00:00 hours; moderate to almost perfect), and night-time (00:00-05:00 hours; small to moderate) HRV. Various moderate-to-large correlations were detected between resting HRV and the rest-to-match day difference in HRV. The rest-to-match day differences of low and high-frequency bands ratio (LF/HF) and HR in the post-match period were moderately correlated with time spent at different exercise intensities. Yo-Yo IR1 performance was highly correlated with jump capacity and peak lactate, but not with any HRV parameter. These results suggest that a greater resting HRV may allow referees to tolerate stresses during a match day with referees who spent more time at higher intensities during matches exhibiting a greater LF/HF increment in the post-match period. The relationship between match activities, [Formula: see text] and HR recovery kinetics in referees and team sport athletes of different competitive levels remains to be clarified.