An Individualized Intervention Increases Sleep Duration in Professional Athletes.

ABSTRACT: Sargent, C, Lastella, M, Schwerdt, S, and Roach, GD. An individualized intervention increases sleep duration in professional athletes. J Strength Cond Res 35(12): 3407-3413, 2021-Athletes typically obtain less sleep than is generally recommended for healthy adults. The aim of this study was to determine whether individualized feedback could increase sleep duration in professional cricket players in the 3 weeks before the start of the domestic season. Players were randomly assigned to a control group (i.e., no individual feedback; n = 8) or an intervention group (i.e., individual feedback about bedtime, wake time, and sleep duration; n = 7). Night-time sleep and daytime naps were monitored using wrist activity monitors in conjunction with self-report sleep diaries for 1 week before, and 1 week after, the feedback intervention. Cumulative sleep duration was calculated as the sum of the sleep duration for a night-time sleep episode and any naps that occurred on the following day. Differences in cumulative sleep duration before and after the intervention were examined using a mixed-effects analysis of variance. There was an interaction between group and week for cumulative sleep duration (p = 0.039; η2 = 0.6; large). The average cumulative sleep duration was longer (+36 minutes) in the intervention group in week 2 compared with week 1. Individualized feedback can be used to increase sleep duration in professional cricket players. In future, it will be important to determine whether improvements in sleep duration can be maintained throughout the season.

External and internal workload demands of women's twenty 20 cricket competition.

OBJECTIVE: To quantify the external and internal workloads of women's Twenty-Twenty (T20) cricket and compare match demands between International, National and Youth level cricket players. DESIGN: A retrospective analysis of data collected form T20 matches played by Australian teams (International level, n = 3; National level, n = 12; Youth level, n = 4) during the 2016-17 Australian cricket season. METHOD: Thirty-four women's T20 cricket players playing for the Australian (International; n = 10), South Australian (National; n = 11) and South Australian Youth (Youth; n = 13) teams participated in the study. Global Positioning System devices captured player movements during matches including distance (metres [m]), PlayerLoad (arbitrary units [AU]), and distance covered at different velocities. A smartphone app was used to capture the sessional rating of perceived exertion (sRPE) for each match Multilevel mixed-effects linear regression was performed for each outcome to evaluate the differences between player level (International, National and Youth). Statistical significance was set at p < 0.05. RESULTS: International players covered the most total distance per match (International players 5250 ±â€¯1664 m, National players 4113 ±â€¯885 m, Youth players 3436 ±â€¯1026 m, p < 0.003 for main effect) and covered more distance at >21 km/h (i.e. high speed running; International players 73 ±â€¯62 m, National players 31 ±â€¯28 m, Youth players 20 ±â€¯4 m, p < 0.003). PlayerLoad was greatest in International players (426 ±â€¯143 AU) compared to National players (391 ±â€¯84 AU) and Youth players (290 ±â€¯4 0 AU) (p < 0.001). sRPE was lower for International players (352 ±â€¯77 AU) and National players (398 ±â€¯58 AU) compared with Youth players (499 ±â€¯171 AU) (p < 0.005). CONCLUSIONS: The external workload of women's T20 cricket matches became greater as the level of competition increased from Youth to National to International, but Youth players perceive the match demands as greater.

Accelerometer detected lateral sway during a submaximal running test correlates with endurance exercise performance in elite Australian male cricket players.

OBJECTIVE: To identify whether movement patterns during a standardized submaximal running test (SSRT), assessed by accelerometry, were associated with improvements in endurance exercise performance. DESIGN: A retrospective analysis of data collected from the 2018-2019 Australian cricket preseason. METHODS: Thirty-nine high-performance male cricket players were studied (25±3 years, 82±6kg, 183±6cm). SSRT was performed monthly prior to a two kilometre (km) running time trial (2kmTT). SSRT involved running between markers, positioned twenty metres apart, for three minutes. Foot strikes were timed to a metronome (154beats/min) to elicit a running speed of ˜eight km/h. Triaxial accelerometers were worn in vests on the upper back and used to assess PlayerLoad medio-lateral vector (PL1Dside%), vertical vector (PL1Dup%) and anterior-posterior vector (PL1Dfwd%) were assessed. RESULTS: 2kmTT performance improved over the study period (p<0.05). PlayerLoad vectors during the first minute of SSRT were not related to 2kmTT performance (p>0.23). During the second and third minutes there were positive associations between 2kmTT (run time) and PL1Dside% (SSRT2min, ß 2.12, p<0.03, 95% CI: 0.22-4.01; SSRT3min, ß 2.30, p<0.03, 95% CI:0.32-4.29), but not PL1Dup% (SSRT2min, ß -0.15, p=0.77, 95% CI: -1.13-0.83; SSRT3min, ß -0.15, p=0.77, 95% CI: -1.11-0.87) or PL1Dfwd% (SSRT2min, ß -0.45, p=0.42, 95% CI: -1.49-0.62; SSRT3min, B-0.45, p=0.40, 95% CI: -1.51-0.60). CONCLUSION: Assessment of PL1Dside% during the second or third minutes of SSRT may inform how an athlete's endurance exercise performance is responding to changes in training load.