The National Interscholastic Cycling Association (NICA) Mountain Biking Injury Surveillance System (ISS): Analysis of 66,588 Student Athlete-Years of Injury Data

Interscholastic youth cross-country mountain bike racing in the United States has grown significantly over the past decade, yet little is known about the risk profile in this age group. Aiming to protect participants, we implemented a prospective, longitudinal injury surveillance system for the purpose of better understanding youth mountain biking injuries and implementing safety measures. Data were collected during competition years 2018–2020, totaling 66,588 student athlete-years. Designated reporters from each team received weekly emails with exposure and incident report forms. Variables analyzed included demographic, rider-related, trail-related, and other data. Injury characteristics during the COVID-19 pandemic in 2020 were compared to the years 2018 and 2019. More student athletes participated in the 2020 season (25,261) than in prior seasons (18,575 in 2018 and 22,752 in 2019). During competition year 2020, overall injury proportion was lower (1.7% versus 3.0% in 2018 and 2.7% in 2019). Variables associated with injury, body part injured, type of injury, time-loss, and disposition following injury were similar between all years. Despite the pandemic and resultant changes to competition, student athletes continued to ride their bikes and become injured, but the proportion of injuries differed. This report details injury characteristics in youth mountain bike racing, including a comparison of before and during the pandemic.

Trends in sports-related emergency department visits in the Netherlands, 2009–2018

ObjectivesWe aim to describe time trends of severe sports-related emergency department (ED) visits in the Netherlands, from 2009 to 2018.MethodsData were extracted from the Dutch Injury Surveillance System by age, gender, sports activity and injury diagnosis, from 2009 to 2018. Absolute numbers and time trends of severe sports-related ED visits were calculated.ResultsBetween 2009 and 2018, the overall numbers of severe sports-related ED visits in the Netherlands have significantly decreased by 14% (95% CI −19% to −9%). This trend was seen among men (−12%; 95% CI −18% to −6%), women (−19%; 95% CI −26% to −11%) and individuals aged 18–34 years (−19%; 95% CI −28% to −10%). The number of ED visits has significantly decreased over time in soccer (−15%; 95% CI −24% to −6%), ice-skating (−80%; 95% CI −85% to −73%) and in inline/roller skating (−38%; 95% CI −55% to −15%). This was not the case in road cycle racing (+135%; 95% CI +85% to +198%) and mountain bike racing (+80%; 95% CI +32% to+146%). In terms of sports injury diagnoses, the number of fractured wrists (−15%; 95% CI −24% to −5%), fractured hands (−37%; 95% CI −49% to −21%), knee distortions (−66%; 95% CI −74% to −55%), and fractured lower legs (−38%; 95% CI −55% to −14%) significantly decreased over time.ConclusionOur study shows a promising reduction in the number of severe sports-related ED visits across most age groups and sports activities. As the number of ED visits increased in road cycle and mountain bike racing, it is important to find out what caused these increases. Furthermore, it is essential to determine trends in exposure hours and to evaluate and implement injury prevention programmes specific for these sports activities.

Physiological characteristics and performance in elite enduro mountain biking.

Enduro mountain bike racing is composed of several timed predominantly downhill race stages linked by time restricted, non-competitive transition stages. This study aimed to 1) detail and compare the laboratory assessed physiological characteristics of elite and non-elite enduro mountain bike riders, and 2) evaluate the use of 10Hz global positioning systems (GPS) unit including a 100Hz triaxial accelerometer to define the demands of enduro mountain bike racing and identify components of successful performance. Eleven (n=11) male enduro mountain bike riders completed laboratory protocols for peak aerobic capacity (VO2peak), onset of blood lactate accumulation at 2 and 4 mmol/L (OBLA2 and OBLA4 respectively), intermittent sprint test (EST), and anthropometry measures. Participants were divided into elite (n=5) and non-elite (n=6) groups for analysis. Nine (n=9) elite enduro mountain bike athletes participated in field data collection at an international enduro mountain bike race. Two race stages were used for analysis of velocity, accumulated load, heart rate and time to complete specific sections of track calculated from GPS units placed on the bicycle seat mast and the rider’s torso. Elite athletes produced greater power during the EST and at VO2peak, OBLA2, OBLA4 when compared to non-elite riders (all p<0.05) with no significant differences in anthropometry (p>0.05). Accumulated load was significantly greater on the bicycle than the rider on both stages (p<0.05) and accumulated load in both locations was significantly higher during stage two compared to stage 1 reflecting differences in terrain (p<0.05). GPS analysis allowed detailed analysis of performance showing winning performances were characterised by reduced time to complete technical downhill and non-technical climbing sections during stage one and technical downhill sections only during stage two. In conclusion, successful performance in enduro mountain bike racing requires adequate skill and technique to sustain high velocities over technical terrain coupled with large aerobic and anaerobic capacities.