Barriers and Motivators of Young Dutch Elite Athletes for Optimizing Their Nutritional Intake

Many young elite athletes do not meet their daily energy and nutrient requirements. However, little research has been done on why these athletes do not meet their daily needs. The aim was to research the barriers and motivators of young Dutch elite athletes to optimize their nutritional intake. Quantitative and qualitative research was conducted among 8 handball and 4 volleyball players at the Dutch National Sports Center (17.2 ± 0.8 years). First, the nutritional intake was tracked through food diaries and analyzed in Nutritics. Thereupon, five semi-structured interviews based on the COM-B model were carried out. The interviews were transcribed and coded. The athletes had a reduced intake of energy, carbohydrates, vitamins A, C, E, D, calcium, potassium, zinc, and iron compared to their requirements. Seven themes for optimizing their nutritional intake emerged in the interviews: needs assessment, practical translation, portion size, lack of time, involvement, individuality, and food distribution. Barriers that the athletes experienced were that they did not know what their total daily nutritional needs were and how this translates into practice. In addition, the portion size at dinner was too small. They also had little time to eat a full meal due to time pressure from training and school. On the other hand, motivators were receiving meal options to translate their needs into practice with a distribution of moments when they need to eat. Covering these topics in nutritional workshops where athletes actively participate with more individual focus, could contribute to the optimization of their nutritional intake.

Factors Affecting Sea-Level Performance Following Altitude Training in Elite Athletes

Live high train high(LHTH)is the original method of altitude training used by elite athletes to enhance sea-level perfor-mance.Whilst many anecdotal reports featuring world-class performances of elite athletes at sea-level following LHTH exist,well-controlled studies of elite athletes using altitude training under ecologically valid conditions with training well characterised are still lacking.The literature is equivocal when considering the ergogenic potential of LHTH,and given the majority of controlled studies do not report enhanced sea-level performance,some scepticism regarding the efficacy of LHTH persists.Despite this,LHTH remains a popular form of altitude training utilised by elite athletes,with numerous case studies of champion athletes employing LHTH solidifying the rationale for its use during preparation for competition.Discussion of factors affecting the response to LHTH are often related to compromising either the hypoxia induced acceleration of eryth-ropoiesis and production of red blood cells,or the maintenance of oxygen flux and training intensity at altitude.Regarding the former,iron status and supplementation,as well as hypoxic dose are often mentioned.Concerning the latter,reduced oxygen availability at altitude leading to athletes training at lower absolute intensities and the relative intensity of training sessions being clamped as equivalent to sea-level,thus also reducing absolute training intensity are frequently discussed.Other factors including immune function and the timing of competition following LHTH may also contribute to an observed performance.Less considered in the literature are those factors specific to elite athletes,namely the repeated use of altitude camps throughout a season,and the influence this may have on subsequent performance.The current narrative review aimed to summarise the current literature pertaining to LHTH in elite athletes,and furthermore describe several factors affecting performance following altitude training.

Longitudinal trajectories of athlete burnout among young table tennis players: A 3-wave study

Purpose:The purposes of this study were to examine the trajectories of athlete burnout across a 2-month period characterized by high physical,psychological,and social demands to explore(1)whether several subgroups of athletes representing distinct burnout trajectories emerged from the analyses and(2)whether athlete burnout symptoms(reduced accomplishment,sport devaluation,and exhaustion)developed in tandem or whether some burnout dimensions predicted downstream changes in other dimensions(causal ordering model).Methods:One hundred and fifty-nine table tennis players in intensive training centers completed a self-reported athlete burnout measure across 3 time points within a 2-month period characterized by high demands.Data were analyzed through latent class growth analysis.Results:Results of latent class growth analysis showed 3 distinct trajectories for each athlete burnout dimension,indicating not only linear or quadratic change but also stability in longitudinal athlete burnout perceptions.Results also suggested that the 3 dimensions of athlete burnout did not develop in tandem.Rather,the likelihood of belonging to particular emerging trajectories of sport devaluation and physical/emotional exhaustion was significantly influenced by the athletes’perception of reduced accomplishment assessed at Time 1.Thus,reduced accomplishment predicted downstream changes in the 2 other athlete burnout dimensions.Conclusion:As a whole,these results highlighted that the multinomial heterogeneity in longitudinal athlete burnout symptoms needs to be accounted for in future research.

Control and Management in Athletic Training of the Russian National Teams

The article presents wide experience in controlling athletic training aimed at preparation of the Russian national teams for major international competitions. Experimental part of the study has been carried out in the course of training camps and competitions since 2010. Forty Russian national teams in 15 winter and 3 summer Olympic sports participated in the research. Theoretical concepts set forth in the works of Anthony Stafford Beer made a basis of a system of control and management developed for the Russian national winter sports teams. In particular, a five-level system was applied to control athletic training. The authors point out that a system of control over athletic training in elite sport teams should take into account a few important issues： （1） each sport, team and athlete has distinctive features; （2） various aspects of athletic training and their interrelation must be aimed at raising effectiveness of training according to individual training plans; （3） coaches and sport managers must be provided with real-time information necessary for development of long-term and short-term training plans and their timely correction.

Non-enzymatic antioxidant blood plasma profile in the period of high training loads of elite speed skaters in the altitude

At the altitude,hypoxia and training load are key factors in the development of oxidative stress.Altitude-induced oxidative stress is developed due to the depletion of antioxidant potential.In the current study,we examined the non-enzymatic antioxidant profile of blood plasma in 7 males and 5 females specializing in speed skating at a 21-day training camp at 1850m above sea level.Training included:cycling,roller skating,ice skating,strength training,and special training.At the start point and the endpoint,total hemoglobin mass(tHb-mass),hemoglobin concentration,and circulating blood volume were determined.Antioxidant profiles,hypoxic doses,hypoxic impulses,and training impulses were assessed at 3,6,10,14,and 18 days.Antioxidant profiles consisting of“urate”and“thiol”parts were registered with chemiluminometry.In the training dynamics,antioxidant parameters changed individually,but in total there was a decrease in the“urate”capacity by a factor of 1.6(p=0.001)and an increase in the“thiol”capacity by a factor of 1.8(p=0.013).The changes in“urate”capacity positively correlated(r_(S)=0.40)and the changes in“thiol”capacity negatively correlated(r_(S)=−0.45)with changes in tHb-mass.Both exercise and hypoxic factors affect the antioxidant parameters bidirectionally.They correlated with a decrease in thiol capacity and with an increase in urate capacity.The assessment of the non-enzymatic antioxidant profile can be a simple and useful addition to screening the reactive oxygen species homeostasis and can help choose the personalized training schedule,individualize recovery and ergogenic support.

Acute effects of static stretching on peak and end-range hamstring-to-quadriceps functional ratios

AIM: To evaluate if static stretching influences peak and end-range functional hamstring-to-quadriceps(H/Q) strength ratios in elite women athletes. METHODS: Eleven healthy female athletes in an elite competitive level participated to the study. All the participants fulfilled the static stretching or non-stretching(control) intervention protocol in a randomized design on different days. Two static unassisted stretching exercises, one in standing and one in sitting position, were used to stretch both the hamstring and quadriceps muscles during these protocols. The total time for the static stretching was 6 ± 1 min. The isokinetic peak torque measurements for the hamstring and quadriceps muscles in eccentric and concentric modes and the calculations for the functional H/Q strength ratios at angular velocities of 60°/s and 180°/s were made before(pre) and after(post) the control or stretching intervention. The strength measurements and functional strength ratio calculations were based during the entire- and end-range of knee extension.RESULTS: The pre-test scores for quadriceps and hamstring peak torque and end range values were not significantly different between the groups(P > 0.05). Subsequently, although the control group did notexhibit significant changes in quadriceps and hamstring muscle strength(P > 0.05), static stretching decreased eccentric and concentric quadriceps muscle strength at both the 60°/s and 180°/s test speeds(P < 0.01). Similarly, static stretching also decreased eccentric and concentric hamstring muscle strength at both the 60°/s and 180°/s test speeds(P < 0.01). On the other hand, when the functional H/Q strength ratios were taken into consideration, the pre-intervention values were not significant different between the groups both during the entire and end range of knee extension(P > 0.05). Furthermore, the functional H/Q strength ratios exhibited no significant alterations during the entire and end ranges of knee extension both in the static stretching or the control intervention(P > 0.05). CONCLUSION: According to our results, static stretching routine does not influence functional H/Q ratio. Athletes can confidently perform static stretching during their warm-up routines.

Daily heart rate variability of Paralympic gold medallist swimmers： A 17-week investigation

Objectives： Heart rate variability （HRV） can be a simple, non-invasive method of gauging cardiac autonomic nervous system fluctuations across periodised training workloads and taper in elite athlete populations. The purpose of these three case studies was to examine daily cardiac autonomic variations in Paralympic athletes leading in to the Paralympic games. Methods： Three Paralympie gold medallist swimmers were monitored daily for their resting HRV over a 17-week monitoring period leading up to the Paralympic games. Specific time- and frequency-domain measures, along with non-linear indices of HRV were calculated for all analyses. All HRV data were analysed individually using daily values, weekly average values, and average values for rest and training phases. Results： A significant difference in HRV was seen for all variables between athlete 1 and athletes 2 and 3 （amputee disabilities） during the entire monitoring period. Conclusion： Despite minimal long-term changes, both swimming classification and disability type significantly influence HRV during athlete monitoring. An increased understanding of individual responses to training, travel, and other outside influences affecting Paralympic athletes could potentially lead to improved management and monitoring of training workloads for enhanced nerformance.

Is there stability in the performance of elite half-marathoners?

The purpose of this study was to investigate the performance stability of elite half-marathoners of both sexes.The study was composed of 24 elite athletes(12 female and 12 male),ranked among the Senior World TOP20 halfmarathoners,who completed a half-marathon race for at least three consecutive years.Tracking was tested using autocorrelations and Kappa Cohen.Autocorrelation revealed a significant association,but a decrease in correlation among the years in both sexes.The overall weighted kappa showed lower stability in performance for both sexes(K=0.191 and K=-0.245)than for males.These findings suggest that both female and male elite halfmarathoners showed low stability in performance during three events.Besides that,athletes with a better performance tended to present the highest performance stability.It is recommended that coaches track the developmental trajectories of the athletes to comprised the changes in performance across the years,as to provide environmental characteristics that can influence performance.

The Association Between Subjective Wellness Symptoms and Blood Biomarker Data in English Premier League Footballers

The present study investigates the association between subjective wellness symptoms,and categorical point-of-care(POC)blood biomarkers of the free oxygen radical test(FORT),and systemic inflammation through high sensitivity C-reactive protein(Hs-CRP),in English Premier League footballers.Data from 38 male professional elite athletes(Mean Age=25.8,SD=4.4)from the English Premier League were included in the study,with a total of 674 individual testing records collected over an entire Premier League season.A player wellness questionnaire,along with fasted and rested point-of-care blood biomarker testing were collected weekly across the season.The wellness questionnaire collected subjective symptoms of illness and fatigue,while FORT and Hs-CRP were assessed through point-of-care analysis to highlight periods of excessive hydroperoxide production and systemic inflammation.Using a chi square goodness of fit model,results showed that there was a significant association between the frequency of symptoms logged and categorical POC blood biomarker data of FORT and HsCRP(P<0.01).Of the records demonstrating normal levels of Hs-CRP and FORT concentrations,27%logged symptoms with an average of 1.5 symptoms reported per answered record.Comparatively,excessive biomarker values demonstrated 55%of records having symptoms logged,averaging 2.4 symptoms reported per record.