HighlightsThe suggested thresholds to define asymmetries should be defined for strength- and coordination-related tasks separately.Youth ski racers showed greater limb asymmetries than elite skiers.Limb dominance in unilateral leg extension strength is associated with injury risk in youth ski racers.Asymmetries should be described as percentage values based on limb dominance rather than left/right leg dominance.

Alpine ski racing is one of the most popular sports in many countries; nevertheless, selection disadvantages and severe injuries result in high dropout rates. In this review we summarize existing knowledge about the specific challenges associated with selection bias and injuries, and their effects on talent development in ski racing.The relative age effect (RAE) appears in all age categories of national Austrian and international alpine ski racing. Relatively younger athletes seem to only have a chance for selection if they are early maturing. Talent selection processes should consider both the biological maturity status as well as the relative age; additionally, a competition system based on a rotating cut-off date might contribute to a reduction of RAE. Youth and adolescent ski racers report lower injury rates compared to World Cup athletes. The knee was the most affected body part in relation to traumatic injuries. The most frequently reported overuse injuries were knee pain (youth) and low back pain (adolescent level). Athlete-related modifiable risk factors were core strength, neuromuscular control, leg extension strength and limb asymmetries. Based on these findings, prevention measures should be expanded to contribute to long-term injury prevention. In future research more multi-disciplinary, longitudinal studies should be performed.

Physical activity is a promising intervention to restore cognitive function after prolonged sedentary periods. However, little is known about the effect of short physical activity bouts on cognition especially among individuals that are used to physical activity. Therefore, the goal of the present study was to assess the impact of a single ten-minute physical activity bout on the cognitive domain of visual attention compared to sedentary behavior in a population of physically active sport students. Using a randomized controlled design, 51 healthy and physically active sport students [mean age: 22.3 (SD: 2.0) years, 33.3% female] were allocated to one of the following interventions in the break of a two-hour study course: physical activity group (running for ten minutes) and sedentary control group. Visual attention was measured post-intervention using a modified trail making test. Pre-, post-, and 30 min after intervention, perceived attention, and affective states were measured. Between-group comparisons were used to analyze whether visual attention and/or changes in perceived attention or affective states differed between groups. The physical activity group showed significantly higher visual attention post-intervention compared with the sedentary control group, p = 0.003, d = 0.89. Perceived attention, p = 0.006, d = 0.87, and arousal, p < 0.001, d = 1.68, showed a significantly larger pre- and post-intervention increase in the physical activity group compared with the sedentary control group, which was not evident 30 min after intervention. A single ten-minute running intervention in study breaks might help to restore the basal visual attentional domain of cognition after prolonged sedentary periods more effectively compared with common sedentary behavior in breaks between study lessons.

Alpine ski racing is a sport with a high risk of injuries. In order to contribute to the longitudinal career development of young athletes, prevention measures should be elaborated. Therefore, the aim of the present study was to investigate prospectively the role of biological maturity status, and changes in anthropometric characteristics and physical fitness parameters over one season in elite youth ski racers younger than 15 years. Eighty-nine elite youth ski racers (39 females, 50 males), aged 10-14 years (mean age: 12.1 ± 1.3), were investigated. Anthropometric characteristics and physical fitness parameters were assessed prior and after the winter season; traumatic and overuse injuries were recorded over the 32 weeks. Binary logistic regression analyses (R 2 = 0.202-0.188) revealed that the biological maturity (Wald = 4.818; p = 0.028), and changes over the season in the jump agility test (Wald = 4.692; p = 0.03), in body height (Wald = 6.229; p = 0.013), and in leg length (Wald = 4.321; p = 0.038) represented significant injury risk factors. Athletes who could improve their jump agility performance more, had smaller changes in the anthropometric characteristics and who were closer to their peak height velocity were at a lower injury risk. In the context of injury prevention, regular neuromuscular training should be incorporated, and phases of rapid growth have to be considered.

The relative age effect (RAE) represents an asymmetry in birth quarter distribution, favoring athletes born early in the selection year and discriminating against late born athletes. The RAE was proven to be present in all age categories of national and international levels of alpine ski racing. Due to the existence of the RAE in all categories, it can be assumed that a selection error takes place favoring early born and early maturing youth ski racers. However, whether selection strategies have changed during the last years due to the high amount of research done in this field, has not been investigated so far in this sport. Therefore, the aim of the present study was to assess whether the magnitude of the RAE in youth ski racers aged 10–14 years has changed during the last decade by comparing the periods 2005–2009 (“former” athletes) and 2015–2019 (“current” athletes). Pupils of a well-known skiing-specific secondary modern school as well as members of the provincial ski team, who all competed at national levels, were included in the study. Next to the birth months, anthropometric characteristics (body height, weight, body mass index) were assessed. Chi-square tests were used to compare differences between the observed and expected relative age quarter distributions across five age categories (U11–U15). Additionally, Kruskal–Wallis- H -Tests were performed to assess differences in anthropometric characteristics between athletes of the four relative age quarters. Mann–Whitney U -Tests were performed to assess possible differences in anthropometric characteristics between former and current ski racers. A highly significant RAE was present in both former [χ 2 (3, 764) = 60.36; p < 0.001; ω = 0.31] and current youth ski racers [χ 2 (3, 702) = 43.13; p < 0.001; ω = 0.29] with an over-representation of athletes of Q1 (30.3–34.2%) and a clear under-representation of athletes of Q4 (14.8–15.0%). Generally, results indicated no change in the magnitude of the RAE in youth alpine ski racing over the past 10–15 years, emphasizing the robust nature of this phenomenon. No significant differences were found in any of the anthropometric characteristics between athletes of the four relative age quarters in both former and current athletes, indicating that relatively younger athletes of the last relative age quarter seem to have to have advanced anthropometric characteristics for being selected. Changes in the talent selection process should be performed to reduce the impact of the RAE.