Measurement of energy availability in highly trained male endurance athletes and examination of its associations with bone health and endocrine function.

PURPOSE: Despite the introduction of Relative Energy Deficiency in Sport (RED-s) in 2014, there is evidence to suggest that male endurance athletes still present with a high prevalence of low energy availability (LEA). Previous findings suggest that energy availability (EA) status is strongly correlated with impairments in endocrine function such as reduced leptin, triiodothyronine (T3), and insulin, and elevated bone loss. This study aimed to report the current EA status, endocrine function and bone health of highly trained Irish male endurance athletes. METHODS: In this cross-sectional study, participants (n = 3 triathletes; n = 10 runners) completed a 7-day testing period during the competition season using lab-based measures, to ascertain EA status, hormone level and rates of bone metabolism. Serum blood samples were obtained to assess hormone levels and markers of bone metabolism. RESULTS: Mean EA was < 30 kcal/kg lean body mass (LBM)/day in 76.9% of athletes. There was a strong association between LEA and low carbohydrate intake, and lower LBM. Mean levels of insulin, IGF-1 and leptin were significantly lower than their reference ranges. Elevated mean concentrations of ß-CTX and a mean P1NP: ß-CTX ratio < 100, indicated a state of bone resorption. CONCLUSION: The EA level, carbohydrate intake, hormone status and bone metabolism status of highly trained male endurance athletes are a concern. Based on the findings of this study, more frequent assessment of EA across a season is recommended to monitor the status of male endurance athletes, in conjunction with nutritional education specific to EA and the associated risks.

Coaches of youth field sports as delivery agents of injury prevention programmes: how are we training the trainers? A scoping review.

OBJECTIVE: To systematically map the coach education (CE) component of injury prevention programmes (IPPs) for youth field sports by identifying and synthesising the design, content and facilitation strategies used to address competency drivers and behaviour change. DESIGN: Scoping review. DATA SOURCES: PubMed, PsycInfo, EMBASE, CINAHL, SportDiscus and Google Scholar electronic databases were searched using keywords related to IPPs and youth field sports. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Studies of IPPs in youth field sports, that provided 'train-the-trainer' education to coaches as designated delivery agents. RESULTS: 20 studies from two field sports (soccer/football; n=17, Rugby Union; n=3) fulfilled the eligibility criteria. Eleven CE interventions occurred in the preseason and 18 occurred at one time-point (single day). Five studies cited use of a behavioural change theory or model in the design of their CE, most frequently the Health Action Process Approach model (n=5); and use of behavioural change techniques varied. Twelve of twenty studies (60%) reported some form of ongoing support to coaches following the CE primary intervention concurrent with IPP implementation. CONCLUSION: CE that occurs on 1 day (one time-point) is most popular for preparing coaches as delivery agents of IPPs in youth field sports. While recognising pragmatic barriers, more expansive in-service training, support and feedback may enhance the effective implementation of IPPs. TRIAL REGISTRATION NUMBER: https://doi.org/10.17605/OSF.IO/FMHGD.

Prevalence of low energy availability and associations with seasonal changes in salivary hormones and IgA in elite male Gaelic footballers.

PURPOSE: Evidence suggests low energy availability (LEA) is prevalent in elite male Gaelic football (GF) players. Previous research in male and female team sports found LEA may negatively impact endocrine function. The aim of this study was to examine the seasonal variations in energy availability (EA) and its associations with salivary measures in elite male GF players across the competitive season. METHODS: Energy availability was assessed using field-based methods in conjunction with salivary testosterone (s-T), cortisol (s-C) and immunoglobin A (s-IgA) concentrations at pre-season (PRE), in-season (IN) and post-season (POST). RESULTS: 38% reported LEA at PRE, 33% at IN, and 28.5% at POST. s-C, s-T and s-IgA levels were within normal ranges at PRE, IN and POST. Salivary cortisol declined significantly from PRE to IN, remaining reduced at POST. Salivary testosterone decreased significantly from PRE to IN but was significantly elevated at POST compared to IN. Salivary IgA was significantly greater at POST than IN. No significant associations were found between s-C or s-T and EA at any time point. Pre-season s-IgA exhibited a significant inverse association with PRE EA. Decreased s-IgA flow rate and s-IgA secretion rate were significantly associated with decreased EA at PRE. Reduced carbohydrate (CHO) intake was also associated with decreased s-IgA secretion rate at PRE. CONCLUSION: This study suggests that LEA is prevalent in elite male GF players, but is not associated with s-C or s-T. However, EA is associated with s-IgA which may impact the immune system. Therefore, education and interventions surrounding the prevalence and associations of EA should be implemented in this population.

The Effects of High-Repetition Strength Training on Performance in Competitive Endurance Athletes: A Systematic Review and Meta-Analysis.

ABSTRACT: Nugent, FJ, Flanagan, EP, Darragh, I, Daly, L, and Warrington, GD. The effects of high-repetition strength training on performance in competitive endurance athletes: A systematic review and meta-analysis. J Strength Cond Res 37(6): 1315-1326, 2023-The aim of this systematic review and meta-analysis was to evaluate the effects of high-repetition strength training (HRST) on performance in competitive endurance athletes. The methodology followed the Preferred Reporting Items for Systematic Review and Meta-Analysis protocol. A search of databases was performed until December 2020. Inclusion criteria were (a) competitive endurance athletes, (b) ≥4 weeks HRST intervention, (c) control or comparison group, (d) outcome measures of performance (either physiological or time trial performance), and (e) all experimental designs. Quality assessment was performed using the Physiotherapy Evidence Database (PEDro) scale. Of the 615 studies retrieved, 11 studies were included (216 subjects) and 9 studies provided sufficient data for the meta-analysis (137 subjects). The PEDro scale score had a mean of 5 of 10 points (range: 3-6). There was no significant difference between the HRST and control groups (g = 0.35; 95% confidence interval [CI] = -0.38 to 1.07; p = 0.35) or HRST and low-repetition strength training (LRST) groups (g = 0.24; 95% CI = -0.24 to 0.72; p = 0.33). The findings of this review and meta-analysis indicate that HRST does not result in improved performance over a 4- to 12-week period, and the results seem to be similar to LRST. The majority of studies involved recreational endurance athletes and had a mean duration of 8 weeks, which is a limitation of the findings. Future intervention studies should be > 12 weeks in duration and involve well-trained endurance athletes (maximal oxygen uptake [V̇o2max] of >65 ml·kg-1·min-2).

Physical Preparation Strategies of Professional Jockeys.

ABSTRACT: Kiely, M, Warrington, G, McGoldrick, A, and Cullen, S. Physical preparation strategies of professional jockeys. J Strength Cond Res 36(11): 3184-3189, 2022-Professional horse racing is a physically demanding sport. The aim of the study was to examine the physical preparation strategies of jockeys for racing. A questionnaire was developed and validated which comprised of 4 sections; (a) background information, (b) making weight and current associated exercise habits, (c) current physical activity practices, and (d) jockey perceptions of strength and conditioning (S&C) and current practices. Eighty-five jockeys ( n = 38 professional flat, n = 47 professional jump) completed the questionnaire in race course weighing rooms representing 80% of the professional athlete population. In total, 77.6% of jockeys participate in physical activity outside of riding. Jockeys that participated in S&C (42.4%) reported their most frequent type of S&C practice; cardio (52.8%), high-intensity interval training (33.3%), flexibility and mobility training (8.3%), resistance training (5.6%). There was no significant difference in S&C participation between total flat and total jump licenses ( p = 0.530; [PHI] = 0.068). Difficulty making weight was reported by 55.3% of jockeys. Exercise alone was used by 29.4% of jockeys to rapidly reduce weight. There was no significant difference ( p = 0.201, [PHI] = 0.357) between the frequency of rapid weight loss per month for total flat (1.7 ± 1.7) and total jump jockeys (1.6 ± 0.5). This study represents the only published data on the physical preparation strategies of jockeys. Jockeys do not partake in physical activity, which mimics the repeated high-intensity demands of racing. Future research is required to examine the effects of specific S&C interventions on riding performance.

Effects of Long-Haul Travel on Recovery and Performance in Elite Athletes: A Systematic Review.

ABSTRACT: Rossiter, A, Warrington, GD, and Comyns, TM. Effects of long-haul travel on recovery and performance in elite athletes: a systematic review. J Strength Cond Res 36(11): 3234-3245, 2022-Elite athletes are often required to travel long-haul (LH) across numerous time zones for training or competition. However, the extent to which LH travel affects elite athlete performance remains largely unknown. The purpose of this systematic literature review was to critically evaluate available evidence on the effects of LH travel on elite athlete psychometric, physiological, sleep, and performance markers. Electronic database searches of PubMed, SPORTDiscus, Scopus, and Web of Science were conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were eligible for inclusion if subjects were identified as elite athletes who embarked on a LH flight (>6 hours) and used an outcome measurement of recovery or performance after the flight. Studies that were retrospective, used light therapy or pharmacological interventions were not included. Of 2,719 records assessed, 14 studies comprising a total of 197 athletes from 6 sports met the inclusion criteria. There was an increase in perceived jet lag and disturbance to various physiological markers after LH travel; however, there was minimal disturbance in other psychometric markers. Sleep was not negatively affected by LH travel. Of 10 studies that assessed performance, 3 found decrements in indirect markers of performance. Elite athletes perceived themselves to be jet lagged and experienced disturbance to various physiological mechanisms after LH travel; however, the effect on performance was inconclusive. Future research would benefit from higher quality studies with improved control measures, larger sample sizes from a wider variety of sports, and use of ecologically valid measures of circadian rhythm and athletic performance.

The Association Between Training Load Indices and Injuries in Elite Soccer Players.

ABSTRACT: Tiernan, C, Comyns, T, Lyons, M, Nevill, AM, and Warrington, G. The association between training load indices and injuries in elite soccer players. J Strength Cond Res 36(11): 3143-3150, 2022-To investigate the association between contact injuries, noncontact injuries, and training load indices, across different lag periods in elite soccer players. Internal load (session rate of perceived exertion) was collected from 15 elite soccer players over 1 season (40-weeks). Acute (7 days), chronic (28 days), acute:chronic workload ratio (ACWR) (uncoupled), exponentially weighted moving averages (EWMA) ACWR, and 2-, 3-, and 4-week cumulative load were calculated on a rolling weekly basis. Multilevel logistic regression was used to analyze the associations between contact, noncontact injuries, and training load indices, across different lag periods (5 and 7 days). A player was at a significantly higher risk of a noncontact injury 5 days later, if week-to-week acute load changes increased (odds ratio [OR] = 1.97). An increase in EWMA ACWR was associated with an increased risk of both a contact (OR = 1.30) and noncontact injury (OR = 1.35), 5 days later. An increase in 2-week cumulative load (OR = 1.77) was associated with an increased risk of a contact injury 7 days later and 3-week cumulative load (OR = 1.55) 5 days later. These findings suggest that to reduce the potential risk of a noncontact injury, training load should be gradually increased, avoiding an increase in week-to-week acute load change (≥9%) or EWMA ACWR (>1.20). Findings indicated that EWMA ACWR may be a more sensitive measure for detecting a player at a higher risk of an injury than ACWR. Furthermore, a high 2- and 3-week cumulative load was associated with an increased risk of a contact injury, which may indicate accumulated fatigue. Practitioners must note that this study investigated associations with injury risk and not injury prediction.

Parents about parenting dual career athletes: A systematic literature review.

OBJECTIVES: To establish the scientific literature on the parents' view as supporters of dual career (DC) athletes, and to highlight practical implications for the development of education programmes to empower parents in this role. METHOD: ology: The systematic literature review included four electronic databases, from which 438 articles published in English between 1999 and 2019 were retrieved. RESULTS: A total of 14 studies achieved the eligibility criteria (i.e., focus on DC, involving parents as participants) for inclusion. Results show that the 14 studies included in the review were characterised by sample sizes <15 to >50 parents of individual and/or team sports athletes, involving data collection based on interviews, semi-structured interviews focus groups, questionnaires and a survey. A thematic synthesis highlighted a two primary constructs: the individual level and the inter-individual level, respectively. The individual level comprised two main themes: Approach to both Sport and Education, and Stressors and Coping, which included five aspects of parenting. The inter-individual level presented three themes: Relationship with the Athlete; Relationship with the Sport Environment and Relationship with the Academic Environment. CONCLUSIONS: Findings highlighted a relevant parental role in supporting DC athletes and partial information on parental support strategies. In conclusions, the limited sample size and typology of sports, and the partial representativeness of countries have impacted the global application of the main findings. Furthermore, the need of an educational programme for parents and the need of regular parents-athlete-teacher/coach engagement were considered crucial to facilitate successful parental interventions at academic and/or sports levels and to limit the potential negative effects of DC parenting.

Validity of Session-Rate of Perceived Exertion to Quantify Training Loads in Paralympic Swimmers.

ABSTRACT: Sinnott-O'Connor, C, Comyns, TM, and Warrington, GD. Validity of session-RPE to quantify training loads in Paralympic swimmers. J Strength Cond Res 35(9): 2611-2615, 2021-Multiple measures may be used by coaches to quantify training load (TL). The application of heart rate (HR) has limitations in swimming and in Paralympic swimmers, and it may not always be a suitable measure. Therefore, the aim of this study was to determine the validity and reliability of the session-rate of perceived exertion (sRPE) method for quantifying internal TL in Paralympic swimmers. A further aim was to examine the relationship between athlete and coach perceptions of sRPE TL. Four international Paralympic swimmers selected to compete in Rio 2016 Paralympic Games participated in this study. Heart rate, RPE, and session duration were recorded for 30 training sessions of varied intensities across a 6-week home training period to quantify TL. Significant high to very high positive correlations were observed between sRPE and 3 HR-based measures-Banister's, Edwards, and Lucia's TRIMP (r = 0.68, 0.66, 0.74, p < 0.01, respectively). Moderate correlations were observed between sRPE and distance measures (r = 0.53, p < 0.05) but were lower than those observed with HR-based measures. A 2-way analysis of variance identified significant differences in the sRPE ratings between coaches and athletes (F(2, 108) = 170.4, p < 0.01, η2 = 0.75). The results of this study suggest that the sRPE method may be an appropriate monitoring tool for quantifying TL during water-based training using a single measure in Paralympic swimmers.

Concussion History, Reporting Behaviors, Attitudes, and Knowledge in Jockeys.

OBJECTIVE: To examine concussion history, knowledge, and attitudes among Irish professional and amateur jockeys. DESIGN: Cross-sectional survey. SETTING: Questionnaire was distributed through e-mails sent to all licensed jockeys, over social media and during professional and amateur race meetings. PARTICIPANTS: An average of 23.6% (12%-44%) Irish professional and amateur jockeys (n = 119) holding a license in 2017. MAIN OUTCOME MEASURES: Jockeys reported their previous concussion history, actions after their most recent concussion and responded to questions examining their knowledge and attitudes toward concussion. RESULTS: Amateur (32.4%) and professional (19.6%) jockeys, who were never medically diagnosed over their career, suspected that they had sustained a concussion. Jockeys displayed good knowledge of concussion signs and symptoms; yet, one in 2 jockeys would continue to ride out the same day if they suspected they had a concussion. They were less likely if they had a race that day. Reasons for continuing to ride include not considering a concussion as serious (85.7%); risk of losing the ride (84.0%); not wanting to let anyone down (77.8%); and considered it a sign of weakness (74.1%). Risky behavior was more common after a suspected concussion than a medically diagnosed concussion. CONCLUSIONS: Underreporting of concussions is proposed as a serious concern, and concussion understanding and attitudes can impact reporting. To address the issue of underreporting of concussions in Irish horseracing, there is a need to educate jockeys and the wider racing community on the importance of timely concussion assessments and access to appropriate management systems.

Physiological Demands of Professional Flat and Jump Horse Racing.

Kiely, M, Warrington, GD, McGoldrick, A, Pugh, J, and Cullen, S. Physiological demands of professional flat and jump horse racing. J Strength Cond Res 34(8): 2173-2177, 2020-No information is currently available on the effect of race distance on the physiological demands of jockeys. This study aimed to quantify the respective demands of short and long flat and jump race distances. Twenty professional jockeys (10 flat and 10 jump) participated in the study. The subjects initially performed a graded incremental exercise test to volitional exhaustion on a treadmill to determine the peak heart rate (HR) and blood lactate concentrations. Two competitive races (short and long) were then monitored on 2 separate occasions for each jockey type to obtain hydration, HR, blood lactate concentration, and rating of perceived exertion data. Mean distances for the 4 races were: 1,247.2 ± 184.7 m (short flat race), 2,313.4 ± 142.2 m (long flat race), 3,480.2 ± 355.3 m (short jump race), and 4,546.4 ± 194.3 m (long jump race). The mean HR for the long flat race was 151 ± 19 b·min (79 ± 11% of HRpeak), which was significantly lower than all other race distances (p = 0.000, effect size [ES] = 0.469). A longer jump race resulted in a significantly higher reported rate of perceived exertion (RPE) (14 ± 2.8) than the short jump race (11.0 ± 1.5) (p = 0.009, ES = 0.271), whereas no significant difference was revealed between peak HR responses or blood lactate concentrations when comparing other race distances (p < 0.05). The finding of this study supports previous limited research, which suggests that horse racing is a high-intensity sport, whereas RPE and mean HR fluctuate according to the race distance.

Salivary IgA as a Predictor of Upper Respiratory Tract Infections and Relationship to Training Load in Elite Rugby Union Players.

Tiernan, C, Lyons, M, Comyns, T, Nevill, AM, and Warrington, G. Salivary IgA as a predictor of upper respiratory tract infections and relationship to training load in elite rugby union players. J Strength Cond Res 34(3): 782-790, 2020-Upper Respiratory Tract Infections (URTI) are among the most common illnesses reported in athletes. An URTI can result in missed training days, which in turn may lead to performance decrements. The purpose of this study was to investigate the use of salivary immunoglobulin A (sIgA) as a predictor of URTI, while also exploring the relationship to weekly training load in elite rugby union players. Nineteen male elite rugby union players provided morning saliva swabs, biweekly (Monday and Friday), over a 10-week training period. Participants completed an illness log documenting symptoms of URTI. Session Rate of Perceived Exertion (sRPE) was collected to determine training load (sRPE × session duration). Weekly training load was also calculated. Logistic regression was used to analyze the relationship between incidences of URTI with sIgA and training load. Multilevel regression was conducted to compare associations between sIgA and training load. The results found that the likelihood of suffering from an URTI increased when sIgA significantly decreased (p = 0.046). Where sIgA decreased by 65% or more, a player was at a greater risk of contracting an URTI within the following 2 weeks. No association was found between sIgA and training load. In conclusion, sIgA may be a useful predictor for determining the likelihood of players contracting an URTI. This will allow the coach to make informed decisions on training status, helping reduce the risk of players missing training, which may have performance decrements. Coaches will benefit from the fast, easy, and instant results available, to analyze a player's immune function.

The Relationship Between Adductor Squeeze Strength, Subjective Markers of Recovery and Training Load in Elite Rugby Players.

Tiernan, C, Lyons, M, Comyns, T, Nevill, AM, and Warrington, G. The relationship between adductor squeeze strength, subjective markers of recovery and training load in elite Rugby players. J Strength Cond Res 33(11): 2926-2931, 2019-The adductor squeeze strength test has become a popular training monitoring marker, particularly in team sports. The aim of this study was to investigate the relationship between adductor squeeze strength scores, subjective markers of recovery and training load in elite Rugby Union players, because of limited research in this area. Nineteen elite male Rugby Union players completed daily monitoring markers (adductor squeeze strength and 5 selected subjective markers of recovery), over a 10-week preseason training period. Rate of perceived exertion (RPE) was collected to determine training load (session RPE; RPE × session duration) and to calculate weekly training load. Spearman's correlation was used to analyze the relationship between adductor squeeze strength scores, subjective markers of recovery, and weekly training load. The results found that where adductor squeeze scores decreased, both perceived fatigue levels (r = -0.335; R = 11.2%; p < 0.001) and muscle soreness (r = -0.277; R = 7.7%; p < 0.001) increased. A weak correlation was found between Monday adductor squeeze strength scores and the previous week's training load (r = -0.235; R = 5.5%; p < 0.001) and Friday adductor squeeze strength scores and the same week's training load (r = -0.211; R = 4.5%; p < 0.05). These results show that adductor squeeze strength may provide coaches with a time-efficient, low-cost objective, player monitoring marker. Additionally, the combination of adductor strength squeeze, with subjective markers, perceived fatigue, and muscle soreness, and appropriately planned training load may help coaches to optimize training adaptations by determining a player's training status.

HIIT enhances endurance performance and aerobic characteristics more than high-volume training in trained rowers.

This study compared the effects of long slow distance training (LSD) with high-intensity interval training (HIIT) in rowers. Nineteen well-trained rowers performed three tests before and after an 8-week training intervention: (1) 2000 m time trial; (2) seven-stage incremental step test to determine maximum oxygen uptake ([Formula: see text]O2max), power output at [Formula: see text]O2max (W[Formula: see text]O2max), peak power output (PPO), rowing economy and blood lactate indices and (3) seven-stroke power-output test to determine maximal power output (Wmax) and force (Fmax). After baseline testing, participants were randomly assigned either to a HIIT or LSD group. The LSD comprised 10 weekly aerobic sessions. The HIIT also comprised 10 weekly sessions: 8 aerobic and 2 HIIT. The HIIT sessions comprised 6-8 × 2.5 min intervals at 100% PPO with recovery time based on heart rate (HR) returning to 70% HRmax. Results demonstrated that the HIIT produced greater improvement in 2000 m time trial performance than the LSD (effect size (ES) = 0.25). Moreover, the HIIT produced greater improvements in [Formula: see text]O2max (ES = 0.95, P = 0.035) and power output at lactate threshold (WLT) (ES = 1.15, P = 0.008). Eight weeks of HIIT performed at 100% PPO is more effective than LSD in improving performance and aerobic characteristics in well-trained rowers.

Kinetic changes during a six-week minimal footwear and gait-retraining intervention in runners.

An evaluation of a six-week Combined minimal footwear transition and gait-retraining combination vs. gait retraining only on impact characteristics and leg stiffness. Twenty-four trained male runners were randomly assigned to either (1) Minimalist footwear transition Combined with gait-retraining over a six-week period ("Combined" group; n = 12) examined in both footwear, or (2) a gait-retraining group only with no minimalist footwear exposure ("Control"; n = 12). Participants were assessed for loading rate, impact peak, vertical, knee and ankle stiffness, and foot-strike using 3D and kinetic analysis. Loading rate was significantly higher in the Combined group in minimal shoes in pre-tests compared to a Control (P ≤ 0.001), reduced significantly in the Combined group over time (P ≤ 0.001), and was not different to the Control group in post-tests (P = 0.16). The impact peak (P = 0.056) and ankle stiffness reduced in both groups (P = 0.006). Loading rate and vertical stiffness was higher in minimalist footwear than conventional running shoes both pre (P ≤ 0.001) and post (P = 0.046) the intervention. There has a higher tendency to non-rearfoot strike in both interventions, but more acute changes in the minimalist footwear. A Combined intervention can potentially reduce impact variables. However, higher loading rate initially in minimalist footwear may increase the risk of injury in this condition.

Effects of Low-Volume, High-Intensity Training on Performance in Competitive Swimmers: A Systematic Review.

Nugent, FJ, Comyns, TM, Burrows, E, and Warrington, GD. Effects of low-volume, high-intensity training on performance in competitive swimmers: a systematic review. J Strength Cond Res 31(3): 837-847, 2017-The purpose of this systematic review was to examine the extent and quality of the current research literature to determine the effects of low-volume, high-intensity training (HIT) on physiological performance and swimming performance in competitive swimmers. The methodology followed the preferred reporting items for systematic review and meta-analysis protocol. A search of relevant databases and conference proceedings was performed until December 2015. The inclusion criteria were (a) competitive swimmers, (b) ≥4 weeks HIT intervention, (c) comparison group had to involve a higher training volume, (d) outcome measures of physiological and swimming performance, and (e) all experimental study designs. Quality assessment was performed using the Quality Index checklist. Results indicate that of the 538 studies retrieved, 7 studies met the inclusion criteria. Six of the 7 studies found that an HIT intervention resulted in significant improvements in physiological performance. Four of the 7 studies found that HIT resulted in significant improvements in swimming performance, whereas none of the 7 studies resulted in a reduction in physiological or swimming performance. Despite the positive findings of this review, the short study duration is a limitation to a number of studies. The current evidence on the effects of HIT on performance is promising; however, it is difficult to draw accurate conclusions until further research has been conducted.

Duty hours and incidents in flight among commercial airline pilots.

INTRODUCTION: Working long duty hours has often been associated with increased risk of incidents and accidents in transport industries. Despite this, information regarding the intermediate relationship between duty hours and incident risk is limited. This study aimed to test a work hours/incident model to identify the interplay of factors contributing to incidents within the aviation industry. METHODS: Nine hundred and fifty-four European-registered commercial airline pilots completed a 30-item survey investigating self-report attitudes and experiences of fatigue. Path analysis was used to test the proposed model. RESULTS: The fit indices indicated this to be a good fit model (χ(2) = 11.066, df = 5, p = 0.05; Comparative Fit Index = 0.991; Normed Fit Index = 0.984; Tucker-Lewis Index = 0.962; Root Mean Square of Approximation = 0.036). Highly significant relationships were identified between duty hours and sleep disturbance (r = 0.18, p < 0.001), sleep disturbance and fatigue in the cockpit (r = 0.40, p < 0.001), and fatigue in the cockpit and microsleeps in the cockpit (r = 0.43, p < 0.001). DISCUSSION: A critical pathway from duty hours through to self-reported incidents in flight was identified. Further investigation employing both objective and subjective measures of sleep and fatigue is needed.

The impact of making-weight on cognitive performance in apprentice jockeys.

Jockeys regularly engage in rapid weight-loss practices in preparation for competition. These practices are thought to impair cognitive function, although the evidence in support of this theory remains inconclusive. The purpose of this study was to examine the effects of making-weight on cognitive function in apprentice jockeys in a simulated and competitive environment. Apprentice jockeys (n = 12) reduced their body mass by 4% in 48 h in a simulated environment using weight-loss methods typically adopted in preparation for racing. Simple and choice reaction time, attention, learning and memory were assessed before and after the weight loss. A further 10 apprentice jockeys performed the cognitive function assessment in a competitive racing environment at both a self-reported "normal" and "light" body mass. Hydration status and body mass were assessed in all trials. In the simulated environment, body mass was reduced by 4.2 ± 0.3%, yet no change in cognitive function was observed. Cognitive function also remained unchanged in the competitive environment after a body mass loss of 5.7 ± 1.9%. Typical reductions in body mass in preparation for racing have no effect on cognitive function in apprentice jockeys in a simulated and competitive environment. Further research is required to investigate the physiological mechanisms preventing the adverse effects of making-weight on cognitive function in jockeys.

Physiological Demands of Flat Horse Racing Jockeys.

The physiological demands of jockeys during competition remain largely unknown, thereby creating challenges when attempting to prescribe sport-specific nutrition and training guidelines. The purpose of this study was to evaluate the physiological demands and energy requirements of jockeys during flat racing. Oxygen uptake (V[Combining Dot Above]O2) and heart rate (HR) were assessed in 18 male trainee jockeys during a race simulation trial on a mechanical horse racing simulator for the typical time duration to cover a common flat race distance of 1,400 m. In addition, 8 male apprentice jockeys participated in a competitive race, over distances ranging from 1,200 to 1,600 m, during which HR and respiratory rate (RR) were assessed. All participants performed a maximal incremental cycle ergometer test. During the simulated race, peak V[Combining Dot Above]O2 was 42.74 ± 5.6 ml·kg·min (75 ± 11% of V[Combining Dot Above]O2peak) and below the mean ventilatory threshold (81 ± 5% of V[Combining Dot Above]O2peak) reported in the maximal incremental cycle test. Peak HR was 161 ± 16 b·min (86 ± 7% of HRpeak). Energy expenditure was estimated as 92.5 ± 18.8 kJ with an associated value of 9.4 metabolic equivalents. During the competitive race trial, peak HR reached 189 ± 5 b·min (103 ± 4% of HRpeak) and peak RR was 50 ± 7 breaths per minute. Results suggest that horse racing is a physically demanding sport, requiring jockeys to perform close to their physiological limit to be successful. These findings may provide a useful insight when developing sport-specific nutrition and training strategies to optimally equip and prepare jockeys physically for the physiological demands of horse racing.

The impact of making weight on physiological and cognitive processes in elite jockeys.

PURPOSE: To examine the impact of making weight on aerobic work capacity and cognitive processes in a group of professional jockeys. METHODS: Nine male jockeys and 9 age-, gender-, and BMI-matched controls were recruited to take part in two experimental trials, conducted 48 hr apart. The jockeys were asked to reduce their body mass by 4% in the 48 hr between trials, and controls maintained usual dietary and physical activity habits between trials. Aerobic work capacity was assessed by performance during an incremental cycle ergometer test. Motor response, decision making, executive function, and working memory were assessed using a computerized cognitive test battery. RESULTS: The jockey group significantly reduced their body mass by 3.6 ± 0.9% (p < .01). Mean urine specific gravity (Usg) readings increased from 1.019 ± 0.004-1.028 ± 0.005 (p < .01) following this reduction in body mass. Peak work capacity was significantly reduced between trials in the jockey group (213 ± 27 vs. 186 ± 23 W, p < .01), although VO2peak (46.4 ± 3.7 vs. 47.2 ± 6.3 ml·kg·min-1) remained unchanged. No changes were identified for any cognitive variable in the jockey group between trials. CONCLUSION: Simulation of race day preparation, by allocating a weight that is 4% below baseline body mass caused all jockeys to report for repeat testing in a dehydrated state, and a reduction in aerobic work capacity, both of which may impact on racing performance.