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Members of racial/ethnic minority groups have a lower lifetime prevalence than have Whites of mental disorders, a risk factor for suicide attempts; paradoxically, however, lesbian, gay, and bisexual (LGB) ethnic minority youths may be at increased risk for suicide attempts relative to White LGB youths. We found that the increased risk of suicide attempts among racial/ethnic minority LGB respondents in our sample relative to White respondents was not explained by excess youth onset of depression and substance abuse or by a higher susceptibility to suicide in the racial/ethnic minority LGB group.

Sleep is considered vital to human health and well-being, and is critical to physiological and cognitive functioning. Elite athletes experience high training and competition demands, and are often exposed to various factors, situations, and environments that can cause sleep impairments. Previous research has shown that athletes commonly experience sleep loss in the lead up to and following competition, which could have significant impacts on their preparation, performance, and recovery. In particular, the results from previous research show significant reductions in total sleep time (~1:40 h:min) and significant increases in sleep latency (~45 minutes) following evening competition. Napping is common in both the training and competition setting in athletes; however, research on the effect of napping on physiology and performance is limited. In contrast, research on strategies and interventions to improve sleep are increasing in the athletic population, with sleep hygiene research resulting in significant improvements in key sleep indices. This review investigates the physiological importance of sleep in athletes, current tools to monitor athletes’ sleep, the role of sleep for cognitive functioning and athletic performance, the prevalence of sleep disturbances and the potential mechanisms causing sleep disturbances, the role of napping, and different intervention strategies to improve sleep.

The findings from the study would suggest that a short nap (<20 min) on the day of competition can enhance jump velocity and improve subjective performance in elite netball players, as assessed by coaching staff.

The use of counter-movement jumps as a measure of neuromuscular performance in athletes has become common in the sport setting. Accurate methods of measuring jump parameters are often expensive, difficult to transport and require expert knowledge. A new smartphone application (My Jump) claims to be a valid and reliable tool for assessing jump height but is yet to be evaluated by independent researchers. Sixty-one recreational athletes (30 male/31 female, mean AE SD; age: 20 AE 4 years) each performed three counter-movement jumps (totalling 183 jumps) on a force plate following a standardised warm-up. All jumps were recorded using an iPhone 6 s and analysed for jump height (m) and flight time (s) using the My Jump application. Jumps were compared between a force plate and My Jump for validity with inter-scorer reliability also assessed. Results show that My Jump is valid (mean bias ¼ 0.9 cm, r ¼ 0.96) and reliable (typical error of estimate ¼ 1.4 cm) for assessing jump performance in recreational athletes using an iPhone 6 s with a 240 Hz high-speed camera. My Jump is a cost-effective and easy-to-use alternative for measuring vertical jump performance without the need for specialist equipment or expertise.

Actigraphy has become a common method of measuring sleep due to its non-invasive, cost-effective nature. An actigraph (Readiband™) that utilizes automatic scoring algorithms has been used in the research, but is yet to be evaluated for its inter-device reliability. A total of 77 nights of sleep data from 11 healthy adult participants was collected while participants were concomitantly wearing two Readiband™ actigraphs attached together (ACT1 and ACT2). Sleep indices including total sleep time (TST), sleep latency (SL), sleep efficiency (SE%), wake after sleep onset (WASO), total time in bed (TTB), wake episodes per night (WE), sleep onset variance (SOV) and wake variance (WV) were assessed between the two devices using mean differences, 95% levels of agreement, intraclass correlation coefficients (ICC), typical error of measurement (TEM) and coefficient of variation (CV%) analysis. There were no significant differences between devices for any of the measured sleep variables (p>0.05). TST, SE, SL, TTB, SOV and WV all resulted in very high ICC's (>0.90), with WASO and WE resulting in high ICC's between devices (0.85 and 0.80, respectively). Mean differences of −2.1 and 0.2 min for TST and SL were associated with a low TEM between devices (9.5 and 3.8 min, respectively). SE resulted in a 0.3% mean difference between devices. The Readiband™ is a reliable tool for researchers using multiple devices of this brand in sleep studies to assess basic measures of sleep quality and quantity in healthy adult populations.

Stress hormone and sleep differences in a competition versus training setting are yet to be evaluated in elite female team-sport athletes. The aim of the current study was to evaluate salivary cortisol and perceptual stress markers during competition and training and to determine the subsequent effects on sleep indices in elite female athletes. Ten elite female netball athletes (mean ± SD; age: 23 ± 6 years) had their sleep monitored on three occasions; following one netball competition match (MATCH), one netball match simulation session (TRAIN), and one rest day (CONTROL). Perceived stress values and salivary cortisol were collected immediately pre- (17:15 pm) and post-session (19:30 pm), and at 22:00 pm. Sleep monitoring was performed using wrist actigraphy assessing total time in bed, total sleep time (TST), efficiency (SE%), latency, sleep onset time and wake time. Cortisol levels were significantly higher (p < .01) immediately post MATCH compared with TRAIN and CONTROL (mean ± SD; 0.700 ± 0.165, 0.178 ± 0.127 and 0.157 ± 0.178 μg/dL, respectively) and at 22:00 pm (0.155 ± 0.062, 0.077 ± 0.063, and 0.089 ± 0.083 μg/dL, respectively). There was a significant reduction in TST (-118 ± 112 min, p < .01) and SE (-7.7 ± 8.5%, p < .05) following MATCH vs. TRAIN. Salivary cortisol levels were significantly higher, and sleep quantity and quality were significantly reduced, following competition when compared to training and rest days.