Somatotypes of premenarcheal athletes and non-athletes

One-hundred thirty-four premenarcheal girls between the ages of 7 and 15 years were somatotyped according to the Health-Carter technique. Sexual maturation was determined by self-assessed Tanner stages. Statistical analysis was completed on 50 athletes (representing seven sports) and 29 non-athletes over the age of 10 years. The mean somatotype for the athletes was calculated to be 2.4-3.6-3.9 and for the non-athletes 3.7-3.7-3.6. Single component ANOVA's revealed that the athletes were significantly less endomorphic (p less than 0.01) than the non-athletes. The overall somatotype ratings and the equality of dispersion about the means were significantly different between the athletes and non-athletes. The single highest category for the athletes was mesomorph-ectomorph and for the non-athletes, mesomorphic-endomorph. Significant negative correlations were obtained between mesomorphy and breast development (-0.33, p less than 0.05) and mesomorphy and pubic hair development (-0.44, p less than 0.01) for the athletes. Significant positive correlations were obtained between endomorphy and breast development (0.55, p less than 0.01) and endomorphy and pubic hair development (0.45, p less than 0.05) for the non-athletes. The mean somatotype for the gymnasts was 2.1-3.9-3.6 and for the swimmers 2.5-3.4-4.1. These two groups were significantly different from each other on each separate component and overall somatotype, but not in equality of dispersion. The results support the conclusion that premenarcheal athletes are morphologically different from non-athletes despite their youth and from each other based on sport specificity.     

Efficient and Regular Patterns of Nighttime Sleep are Related to Increased Vulnerability to Microsleeps Following a Single Night of Sleep Restriction

Sleep-deprived people, or those performing extended monotonous tasks, can exhibit brief episodes in which they suspend performance and appear to fall asleep momentarily—behavioral microsleeps (“microsleeps”). In this study, microsleeps were identified using eye video and tracking response during a 20-min continuous tracking task undertaken by 16 healthy volunteers (mean age 24.9?yrs; 8 females, 8 males) in the early afternoon following a normally rested night and a night of restricted sleep (time-in-bed restricted to 4?h). Sessions were 1 wk apart and counterbalanced. Wrist actigraphy, self-reported sleepiness, and sleep quality were also recorded. We hypothesized that high microsleep rates when normally rested or after a night of sleep restriction would be related to poor sleep quality, sleep disturbance, circadian type, irregular sleep patterns, low daily sleep duration, or poor sleep efficiency. We also hypothesized that prior performance on a 10-min psychomotor vigilance task (PVT) (mean reaction time or number of PVT lapses) would be related to the number of microsleeps during the tracking task and that PVT performance could, therefore, be used as a fitness-for-duty indicator. The number of microsleeps during the tracking task increased following sleep restriction (mean 11.4 versus 27.9; p?=?0.03). There were no correlations between the number of microsleeps in the normally rested session and any of the actigraphically measured or self-reported sleep measures. However, the number of microsleeps following sleep restriction was correlated with sleep efficiency (r?=?0.73, p?=?0.001), sleep onset latency (r?=??0.57, p?=?0.02), and sleep onset time-of-day standard deviation (r?=??0.54, p?=?0.03) over 11 normally rested nights. There was no correlation between PVT performance and the subsequent number of microsleeps during the tracking task in either session. Attributes usually associated with beneficial nighttime sleep patterns—going to sleep at a similar time each night, falling asleep quickly, and infrequent arousals—were related to greater vulnerability to microsleeps following sleep restriction. There were intercorrelations between all the sleep measures associated with microsleep rate following sleep restriction, indicating that the measures form a pattern of behaviors and are not independently related to microsleep rate. Perhaps some people maintain a regular sleep pattern because they experience sleepiness the following day when their pattern is disrupted. Conversely, people with more variation in their sleep pattern may do so because this does not substantially increase sleepiness the following day. We conclude that people with consistent sleep patterns and efficient sleep may be more prone to microsleeps than other people when their usual regular pattern is disrupted by sleep restriction.     

SUBJECTIVE PERCEPTIONS OF THE EFFECTS OF SUSTAINED PERFORMANCE UNDER SLEEP-DEPRIVATION CONDITIONS

In today's society, numerous situations arise in which sleep deprivation is a common occurrence. Subjective perceptions are a vital component to understanding the effects of sustained performance during sleep deprivation, as they may be the first indication of the effects of sustained performance or sleep deprivation on the individual. Using the theoretical framework of the Controlled Attention Model, this study examined the effects of 16?h of sustained performance under 28?h of acute sleep deprivation on perceived effort, motivation, and stress of 24 participants while completing a complex cognitive and a simple vigilance task. Perceived effort increased for both tasks, with higher effort reported on the cognitive than the vigilance task at the beginning of the experimental period, but with higher effort reported on the vigilance than the cognitive task at the end. Subjective motivation decreased for both tasks, with significantly higher levels of motivation on the cognitive than the vigilance task. Perceived stress did not change for either task. Results suggest that functioning under sustained performance and sleep-deprivation conditions affects subjective perceptions differently for cognitive versus vigilance tasks. The controlled attention model offers one means of understanding how different tasks could affect a person's subjective perceptions and ability to perform, in that different levels of controlled attention are required for the two tasks. (Author correspondence: hodle@gettysburg.edu)     

Family Structure as a Correlate of Organized Sport Participation among Youth

Organized sport is one way that youth participate in physical activity. There are disparities in organized sport participation by family-related factors. The purpose of this study was to determine whether non-traditional family structure and physical custody arrangements are associated with organized sport participation in youth, and if so whether this relationship is mediated by socioeconomic status. Data were from the 2009–10 Health Behaviour in School-aged Children survey, a nationally representative cross-section of Canadian youth in grades 6–10 (N = 21,201). Information on family structure was derived from three survey items that asked participants the number of adults they lived with, their relationship to these adults, and if applicable, how often they visited another parent outside their home. Participants were asked whether or not they were currently involved in an organized sport. Logistic regression was used to compare the odds of organized sport participation according to family structure. Bootstrap-based mediation analysis was used to assess mediation by perceived family wealth. The results indicated that by comparison to traditional families, boys and girls from reconstituted families with irregular visitation of a second parent, reconstituted families with regular visitation of a second parent, single-parent families with irregular visitation of a second parent, and single-parent families with regular visitation of a second parent were less likely to participate in organized sport than those from traditional families, with odds ratios ranging from 0.48 (95% confidence interval: 0.38–0.61) to 0.78 (95% confidence interval: 0.56–1.08). The relationship between family structure and organized sport was significantly mediated by perceived family wealth, although the magnitude of the mediation was modest (ie, <20% change in effect estimate). In conclusion, youth living in both single-parent and reconstituted families experienced significant disparities in organized sport participation that was partially mediated by perceived family wealth.     

Comparison of blood pro/antioxidant levels before and after acute exercise in athletes and non-athletes

The aims of our study were to assess the redox state of adolescent athletes and non-athletes both at rest and after acute exposure to physical load and to find relations between parameters of redox state and morphofunctional characteristics of subjects. 58 young handball players and 37 non-athletes were subjected to body composition analysis, measuring of maximal oxygen consumption and blood sampling immediately before and after a maximal progressive exercise test. At rest, athletes had significantly higher superoxide dismutase (SOD) and catalase (CAT) activity, higher levels of glutathione (GSH) and nitric oxide (NO) and lower levels of lipid peroxidation (TBARS) compared with non-athletes. A maximal exercise test induced statistically significant rise of superoxide anion radical (O2-), hydrogen peroxide (H2O2) and NO levels in non-athletes, while TBARS levels decreased. Athletes experienced the fall in NO levels and the fall in CAT activity. After exercise, athletes had significantly lower levels of O2- compared with non-athletes. Two way repeated measures ANOVA showed that the response of O2-, NO and TBARS to the exercise test was dependent on the sports engagement (training experience) of subjects. Significant correlations between morphofunctional and redox parameters were found. These results suggest that physical fitness affects redox homeostasis.     

Enhanced temporal but not attentional processing in expert tennis players

In tennis, as in many disciplines of sport, fine spatio-temporal resolution is required to reach optimal performance. While many studies on tennis have focused on anticipatory skills or decision making, fewer have investigated the underlying visual perception abilities. In this study, we used a battery of seven visual tests that allowed us to assess which kind of visual information processing is performed better by tennis players than other athletes (triathletes) and non-athletes. We found that certain time-related skills, such as speed discrimination, are superior in tennis players compared to non-athletes and triathletes. Such tasks might be used to improve tennis performance in the future.     

Cytokine response to strenuous exercise in athletes and non-athletes--an adaptive response

Exercise and physical strenuous activity have been demonstrated to increase the serum TNF-alpha and IL-6. Regular physical training is expected to attenuate such a response. This study was undertaken to understand the impact of regular exercise training on IL-6 and TNF-alpha in athletes and non-athletes. Ten athletes, who have been on regular training for the past 6 months, and 10 age- and sex-matched subjects (non-athlete group) who had no practice of regular exercise, were recruited. Both were subjected to undergo the same frequency level of strenuous exercise. Blood samples were collected; one before strenuous exercise and the other after the exercise. Plasma cytokines, IL-6 and TNF-alpha, were estimated using Sandwich ELISA method. All participants in the study were male with the athletes' age being 18.00+/-1.3years (mean+/-SD) and the non-athletes were aged 20.00+/-0.6years (mean+/-SD). Majority of the athletes and non-athletes demonstrated a rise in IL-6 and a fall in TNF-alpha levels. Further, the athletes showed a lesser magnitude of change in the cytokine levels following a longer duration of exercise than non-athletes. Athletes appear to have an attenuated cytokine response. Regular physical training has been demonstrated to attenuate the immune response to exercise in either direction.     

Occupational performance of a paced secondary task under conditions of sensory deprivation. I. Heart rate changes in train drivers as a result of monotony

Twelve experienced train drivers were asked to operate the train function safety circuit (SIFA)--a paced secondary motor task which is expected to guarantee the driver's fitness for service on engines of the German Federal Railway--under laboratory conditions of extreme monotony. In spite of massive decreases in vigilance as shown by theta-activity in the EEG, all subjects were able to operate the device without major errors. A prerequisite for adequate performance is an EEG-defined arousal reaction, which is synchronized with the SIFA cycles. For 7 subjects the time-related cross-correlation coefficients between SIFA operation, alpha-activity (indicative of alertness), theta-activity (indicative of reduced vigilance), and heart rate were calculated. The central-nervous arousal found in the EEG corresponded to distinct increases in heart rate. The moments of SIFA operation after phases of light sleep correlated significantly and positively with increases in heart rate. These increases constituted a physiological overcompensation as far as the physical readiness was concerned which reached its peak after the task had been performed satisfactorily, constituting additional and superfluous occupational stress. The results of this study indicate clearly that monotony stress is not a result of occupational monotony itself, but the result of the physiological effort which is required in order to regain a level of alterness which allows adequate performance under monotonous conditions.     

Detecting Body Fat–A Weighty Problem BMI versus Subcutaneous Fat Patterns in Athletes and Non-Athletes

We aimed to describe the relationship between BMI and the subcutaneous adipose tissue topography within young athletes and non-athletic controls, to comparatively evaluate the diagnostic powers of subcutaneous adipose tissue thicknesses at different body sites, furthermore to explore appropriate cut-offs to discriminate between athletes and controls. Measurements were determined in 64 males and 42 females, who were subsequently separated into two even groups (athletes and non-athletes). The optical device LIPOMETER was applied at standardised body sites to measure the thickness of subcutaneous adipose tissue layers. To calculate the power of the different body sites and the BMI to discriminate between athletes and non-athletes, receiver operating characteristic curve analysis was performed. In men, the neck (optimal cut-off value 2.3 mm) and trunk (optimal cut-off value 15.5 mm) provided the strongest discrimination power: with 90.6% (58 of 64) of the subjects being correctly classified into athletes or non-athletes. Discrimination power of the BMI values was 64.1% (41 of 64 were correctly classified). In women, the upper back (optimal cut-off value 3.3 mm) and arms (optimal cut-off value 15.9 mm) provided the strongest discrimination power with 88.1% (37 of 42 being correctly classified). When using BMI to discriminate between athletes and non-athletes only 52.4% (22 of 42) were correctly classified. These results suggest that compared to BMI levels, subcutaneous fat patterns are a more accurate way of discriminating between athletes and non-athletes. In particular the neck and the trunk compartment in men and the upper back and arms compartment in women, were the best sites to discriminate between young athletes and non-athletes on the basis of their fat patterns.     

Quantifying session ratings of perceived exertion for field-based speed training methods in team sport athletes

ABSTRACT: Lockie, RG, Murphy, AJ, Scott, BR, and Janse de Jonge, XAK. Quantifying session ratings of perceived exertion for field-based speed training methods in team sport athletes. J Strength Cond Res 26(10): 2721-2728, 2012-Session ratings of perceived exertion (session RPE) are commonly used to assess global training intensity for team sports. However, there is little research quantifying the intensity of field-based training protocols for speed development. The study's aim was to determine the session RPE of popular training protocols (free sprint [FST], resisted sprint [RST], and plyometrics [PT]) designed to improve sprint acceleration over 10 m in team sport athletes. Twenty-seven men (age = 23.3 ± 4.7 years; mass = 84.5 ± 8.9 kg; height = 1.83 ± 0.07 m) were divided into 3 groups according to 10-m velocity. Training consisted of an incremental program featuring two 1-hour sessions per week for 6 weeks. Subjects recorded session RPE 30 minutes post training using the Borg category-ratio 10 scale. Repeated measures analysis of variance found significant (p < 0.05) changes in sprint velocity and session RPE over 6 weeks. All groups significantly increased 0- to 5-m velocity and 0- to 10-m velocity by 4-7%, with no differences between groups. There were no significant differences in session RPE between the groups, suggesting that protocols were matched for intensity. Session RPE significantly increased over the 6 weeks for all groups, ranging from 3.75 to 5.50. This equated to intensities of somewhat hard to hard. Post hoc testing revealed few significant weekly increases, suggesting that session RPE may not be sensitive to weekly load increases in sprint and plyometric training programs. Another explanation, however, could be that the weekly load increments used were not great enough to increase perceived exertion. Nonetheless, the progressive overload of each program was sufficient to improve 10-m sprint performance. The session RPE values from the present study could be used to assess workload for speed training periodization within a team sports conditioning program.     

Ventilatory and heart rate chemosensitivity in track-and-field athletes

Fifty-four male track-and-field athletes and 18 male non-athletes were examined by isocapnic progressive hypoxia and CO2 rebreathing tests. Ventilatory and heart rate (HR) responses to hypoxia were analysed by a hyperbolic relationship and the ventilatory response to hypercapnia by a linear regression. The results showed that ventilatory sensitivity during hypoxia was significantly attenuated in the long-distance runners and sprinters compared to the non-athletes. Although heart rate sensitivity during hypoxia in none of the athletes showed a significant difference compared to that of the non-athletes, baseline HR in the long-distance runners was significantly lower than that of the non-athletes. None of the athletes showed significant differences in ventilatory sensitivity during hypercapnia compared to the non-athletes.     

Sustained attention performance during sleep deprivation: evidence of state instability

Nathaniel Kleitman was the first to observe that sleep deprivation in humans did not eliminate the ability to perform neurobehavioral functions, but it did make it difficult to maintain stable performance for more than a few minutes. To investigate variability in performance as a function of sleep deprivation, n = 13 subjects were tested every 2 hours on a 10-minute, sustained-attention, psychomotor vigilance task (PVT) throughout 88 hours of total sleep deprivation (TSD condition), and compared to a control group of n = 15 subjects who were permitted a 2-hour nap every 12 hours (NAP condition) throughout the 88-hour period. PVT reaction time means and standard deviations increased markedly among subjects and within each individual subject in the TSD condition relative to the NAP condition. TSD subjects also had increasingly greater performance variability as a function of time on task after 18 hours of wakefulness. During sleep deprivation, variability in PVT performance reflected a combination of normal timely responses, errors of omission (i.e., lapses), and errors of commission (i.e., responding when no stimulus was present). Errors of omission and errors of commission were highly intercorrelated across deprivation in the TSD condition (r = 0.85, p = 0.0001), suggesting that performance instability is more likely to include compensatory effort than a lack of motivation. The marked increases in PVT performance variability as sleep loss continued supports the "state instability" hypothesis, which posits that performance during sleep deprivation is increasingly variable due to the influence of sleep initiating mechanisms on the endogenous capacity to maintain attention and alertness, thereby creating an unstable state that fluctuates within seconds and that cannot be characterized as either fully awake or asleep.     

Light Effects on Behavioural Performance Depend on the Individual State of Vigilance

Research has shown that exposure to bright white light or blue-enriched light enhances alertness, but this effect is not consistently observed in tasks demanding high-level cognition (e.g., Sustained Attention to Response Task—SART, which measures inhibitory control). Individual differences in sensitivity to light effects might be mediated by variations in the basal level of arousal. We tested this hypothesis by measuring the participants’ behavioural state of vigilance before light exposure, through the Psychomotor Vigilance Task. Then we compared the effects of a blue-enriched vs. dim light at nighttime on the performance of the auditory SART, by controlling for individual differences in basal arousal. The results replicated the alerting effects of blue-enriched light, as indexed by lower values of both proximal temperature and distal-proximal gradient. The main finding was that lighting effects on SART performance were highly variable across individuals and depended on their prior state of vigilance. Specifically, participants with higher levels of basal vigilance before light exposure benefited most from blue-enriched lighting, responding faster in the SART. These results highlight the importance of considering basal vigilance to define the boundary conditions of light effects on cognitive performance. Our study adds to current research delineating the complex and reciprocal interactions between lighting effects, arousal, cognitive task demands and behavioural performance.     

Physiological and performance test correlates of prolonged, high-intensity, intermittent running performance in moderately trained women team sport athletes

A large number of team sports require athletes to repeatedly produce maximal or near maximal sprint efforts of short duration interspersed with longer recovery periods of submaximal intensity. This type of team sport activity can be characterized as prolonged, high-intensity, intermittent running (PHIIR). The primary purpose of the present study was to determine the physiological factors that best relate to a generic PHIIR simulation that reflects team sport running activity. The second purpose of this study was to determine the relationship between common performance tests and the generic PHIIR simulation. Following a familiarization session, 16 moderately trained (VO2max = 40.0 +/- 4.3 ml x kg(-1) x min(-1)) women team sport athletes performed various physiological, anthropometrical, and performance tests and a 30-minute PHIIR sport simulation on a nonmotorized treadmill. The mean heart rate and blood lactate concentration during the PHIIR sport simulation were 164 +/- 6 b x min(-1) and 8.2 +/- 3.3 mmol x L(-1), respectively. Linear regression demonstrated significant relationships between the PHIIR sport simulation distance and running velocity attained at a blood lactate concentration of 4 mmol x L(-1) (LT) (r = 0.77, p < 0.05), 5 x 6-second repeated cycle sprint work (r = 0.56, p < 0.05), 30-second Wingate test (r = 0.61, p < 0.05), peak aerobic running velocity (Vmax) (r = 0.69, p < 0.05), and Yo-Yo Intermittent Recovery Test (Yo-Yo IR1) distance (r = 0.50, p < 0.05), respectively. These results indicate that an increased LT is associated with improved PHIIR performance and that PHIIR performance may be monitored by determining Yo-Yo IR1 performance, 5 x 6-second repeated sprint cycle test work, 30-second Wingate test performance, Vmax, or LT. We suggest that training programs should focus on improving both LT and Vmax for increasing PHIIR performance in moderately trained women. Future studies should examine optimal training methods for improving these capacities in team sport athletes.     

Pulmonary blood volume and interventricular circulation time in physically trained and untrained subjects.

Resting pulmonary plasma and blood volumes (PPV and PBV), interventricular circulation time (IVCT), cardiac and stroke index (CI and SI), heart rate (HR), total plasma and blood volumes (PV and BV) were determined in athletes (two male groups representing different types of sport activities, and one female group) and compared with those of non-athletes (one male and one female group). In addition to high maximal aerobic power, the athletes were characterized by greater SI, BV and PV and lower resting HR than non-athletes, PPV and PBV were significantly larger and IVCT significantly longer in the trained than in the untrained groups, probably reflecting an improved capacity of the pulmonary circulation. PPV as per cent of PV was almost equal in all the groups, indicating the same distribution of plasma between the pulmonary and systemic circulation. The data also indicate that total blood volume is an important determinant of the magnitude of the pulmonary vascular bed. The increased volume of flowing blood and increased stroke volume in athletes probably allows for a reduction in flow velocity and thereby a reduction in kinetic energy.     

Relationship between blood lactate and cortical excitability between taekwondo athletes and non-athletes after hand-grip exercise

Objectives: In taekwondo competitions, fatigue has a large influence on performance. Recent studies have reported that the excitability in the primary hand motor cortex, investigated with transcranial magnetic stimulation (TMS), is enhanced at the end of a maximal exercise and that this improvement correlates with blood lactate. The aim of the present study was to investigate the relationship between blood lactate and cortical excitability in taekwondo athletes and non-athletes.

Methods: The excitability of the primary motor cortex was measured before and after fatiguing hand-grip exercise by TMS. Capillary blood lactate was measured at rest (pre-test), at the end (0?min), and at 3 and 10?min after the exercise by using a “Lactate Pro” portable lactate analyzer.

Results: Significant differences in cortical excitability between the two groups were found after the exercise (p?p?Conclusion: The present findings showed changes in the excitability in the athletes group and also in the non-athletes group. However, blood lactate seems to have the greater effect in trained subjects compared to untrained subjects. In fact, it appears that, during extremely intensive exercise in taekwondo athletes, lactate may delay the onset of fatigue not only by maintaining the excitability of muscle, but also by increasing the excitability of the primary motor cortex more than in non-athletes.     

Physical demands, injuries, and conditioning practices of stock car drivers

The purpose of this study was to assess the physical demands, injuries, and conditioning practices of stock car drivers. Forty stock car drivers from 27 states in the United States participated in the interviews for 43.9 ± 13.9 minutes. The interviews examined background information, the physical demands of racing, injuries associated with racing, and the athletic and fitness background and practices of the subjects. Numerical data were analyzed using Pearson's correlation coefficients. Responses to open-ended questions were analyzed using inductive content analysis. Results revealed significant correlation between track points standings and the length of the resistance training sessions (R = -0.71, p = 0.002) and subject self-assessment of their fitness (R = -0.53, p = 0.045). Results also revealed that "upper-body strength" was identified as the most important physical demand. Extreme fatigue was the most common feeling after a demanding race. Subjects reported that shoulder fatigue was the most common form of muscle soreness experienced after a race. Back and torso injuries were the most common injury, although head injuries most frequently required medical attention. The subjects' biggest fear was fire, followed closely by head and neck injury. The bench press and running were the most commonly performed resistance training and cardiovascular exercises, respectively. Subjects reported that their highest motivation for training was to improve their racing performance. Many subjects had athletic backgrounds with football identified as the sport they had most commonly participated in. This study provides additional detailed information. Results of this study can assist strength and conditioning professionals in the development of strength and conditioning programs for performance enhancement and injury prevention that are specific to the needs of this population of athletes.     

Relationship between running loads and soft-tissue injury in elite team sport athletes

Although the potential link between running loads and soft-tissue injury is appealing, the evidence supporting or refuting this relationship in high-performance team sport athletes is nonexistent, with all published studies using subjective measures (e.g., ratings of perceived exertion) to quantify training loads. The purpose of this study was to investigate the risk of low-intensity (e.g., walking, jogging, total distances) and high-intensity (e.g., high acceleration and velocity efforts, repeated high-intensity exercise bouts) movement activities on lower body soft-tissue injury in elite team sport athletes. Thirty-four elite rugby league players participated in this study. Global positioning system data and the incidence of lower body soft-tissue injuries were monitored in 117 skill training sessions during the preseason and in-season periods. The frailty model (an extension of the Cox proportional regression model for recurrent events) was applied to calculate the relative risk of injury after controlling for all other training data. The risk of injury was 2.7 (95% confidence interval 1.2-6.5) times higher when very high-velocity running (i.e., sprinting) exceeded 9 m per session. Greater distances covered in mild, moderate, and maximum accelerations and low- and very low-intensity movement velocities were associated with a reduced risk of injury. These results demonstrate that greater amounts of very high-velocity running (i.e., sprinting) are associated with an increased risk of lower body soft-tissue injury, whereas distances covered at low and moderate speeds offer a protective effect against soft-tissue injury. From an injury prevention perspective, these findings provide empirical support for restricting the amount of sprinting performed in preparation for elite team sport competition. However, coaches should also consider the consequences of reducing training loads on the development of physical qualities and playing performance.     

Sex Attracts: Investigating Individual Differences in Attentional Bias to Sexual Stimuli

We investigated the impact of sexual stimuli and the influence of sexual motivation on the performance in a dot-probe task and a line-orientation task in a large sample of males and females. All pictures (neutral, erotic) were rated on the dimensions of valence, arousal, disgust, and sexual arousal. Additionally, questionnaires measuring sexual interest/desire/motivation were employed. The ratings of the sexual stimuli point to a successful picture selection because sexual arousal did not differ between the sexes. The stimuli were equally arousing for men and women. Higher scores in the employed questionnaires measuring sexual interest/desire/motivation led to higher sexual arousal ratings of the sex pictures. Attentional bias towards sex pictures was observed in both experimental tasks. The attentional biases measured by the dot-probe and the line-orientation task were moderately intercorrelated suggesting attentional bias as a possible marker for a sex-attention trait. Finally, only the sexual sensation seeking score correlated with the attentional biases of the two tasks. Future research is needed to increase the predictive power of these indirect measures of sexual interest.     

PRIOR NIGHT SLEEP DURATION IS ASSOCIATED WITH PSYCHOMOTOR VIGILANCE IN A HEALTHY SAMPLE OF POLICE ACADEMY RECRUITS

Aviation, military, police, and health care personnel have been particularly interested in the operational impact of sleep restriction and work schedules given the potential severe consequences of making fatigue-related errors. Most studies examining the impact of sleep loss or circadian manipulations have been conducted in controlled laboratory settings using small sample sizes. This study examined whether the relationship between prior night sleep duration and performance on the psychomotor vigilance task could be reliably detected in a field study of healthy police academy recruits. Subjects (N?=?189) were medically and psychiatrically healthy. Sleep-wake activity was assessed with wrist actigraphy for 7 days. Subjects performed the psychomotor vigilance task (PVT) for 5?min on a personal digital assistant (PDA) device before and after their police academy workday and on comparable times during their days off. Mixed-effects logistic regression was used to estimate the probability of having ≥1 lapse on the PVT as a function of the previous night sleep duration during the 7 days of field testing. Valid estimates of sleep duration were obtained for 1082 nights of sleep. The probability of a lapse decreased by 3.5%/h sleep the night prior to testing. The overall probability of having a lapse decreased by 0.9%/h since awakening, holding hours of sleep constant. Perceived stress was not associated with sleep duration or probability of performance lapse. These findings demonstrate the feasibility of detecting sleep and circadian effects on cognitive performance in large field studies. These findings have implications regarding the daytime functioning of police officers. (Author correspondence: Thomas.Neylan@ucsf.edu)