Anna Östenberg

Injury risk factors in female European football. A prospective study of 123 players during one season.

The purpose of this study was to register prospectively the injuries in female soccer and to study their correlation to potential risk factors. A total of 123 senior players from eight teams of different levels were followed during one season. Isokinetic knee muscle strength at 60 and 180°/s, one‐leg‐hop, vertical jump, square‐hop, and continuous multistage fitness test (MFT) were tested at the end of the pre‐season. In addition, Body Mass Index (BMI) and general joint laxity were measured. During the season, April–October, all injuries resulting in absence from one practice/game or more were registered. Forty‐seven of the 123 players sustained altogether 65 injuries. The total injury rate was 14.3 per 1000 game hours and 3.7 per 1000 practice hours. The knee (26%) was the most commonly injured region followed by the foot (12%), ankle (11%), thigh (11%) and back (11%). The risk of sustaining moderate and major injuries increased in the later part of the game or practice. Significant risk factors for injuries were an increased general joint laxity (odds ratio (OR)=5.3, P<0.001), a high performance in the functional test square‐hop (OR=4.3, P=0.002), and an age over 25 years (OR=3.7, P=0.01). The injury rate was not different compared to male soccer, but knee injuries were more common, which is in accordance with previous studies. None of the risk factors identified in this study is easily applicable for future intervention studies in the attempts to reduce the injury rate in female soccer.

Isokinetic knee extensor strength and functional performance in healthy female soccer players

östenberg A, Roos E, Ekdahl C, Roos H. Isokinetic knee extensor strength and functional performance in healthy female soccer players.

Physical capacity in female soccer players : does age make a difference?

The overall purpose was to investigate female soccer regarding injuries, risk factors, posttraumatic OA and non-traumatic OA. A prospective study of injuries in eight female soccer teams, from the six available levels, was performed during one season. The total injury rate was 14.3 and 3.7/1000 game and practice hours, respectively. The knee (26%) was the most common place for injury, followed by the foot (12%). An increased general joint laxity was found to be a significant risk factor for general injury and knee injury. In an attempt to find easy functional tests that do not require advanced equipment and that could be used instead of more advanced isokinetic tests, only low correlations between isokinetic strength measurements and functional tests, such as one-leg hop, triple jump, vertical jump, one-leg rising or square hop, were found. There were no differences in any of the tests found between players under /over the age of 20, except for knee flexor muscle strength, where a small but significant difference was seen. Female soccer players with ACL injury showed radiographic changes in the in 69%, and verified knee OA in 34% at the age of 31, 12 years after injury. A majority of the players suffered from symptoms affecting their sport and recreational activities and knee-related quality of life. However, the symptoms were not related to the presence of OA or having undergone surgery to the affected knee or not. Somewhat older female ex-soccer players (mean age 42 years) showed a prevalence of 3% and 17% of radiographic hip and knee OA, and had, with and without knee injuries, a 5-fold increased rate of knee osteoarthrosis compared to non-sporting females age 46, when age and BMI were adjusted for. No difference was seen between the female players and the non-sporting controls regarding hip OA. Increased general joint laxity was found to be a risk factor for injury. Female soccer players with an ACL injury had verified knee OA in 34% at the age of 31, 12 years after injury. Also, somewhat older female players after their career showed a high prevalence of radiographic knee OA and a 5-fold risk of developing knee OA compared to controls. Female soccer by itself and in combination with the high risk of knee injuries has an increased risk of OA. However, the positive effects of exercise, physical and mental, when playing soccer should not be ignored.

Experiences of returning to elite beach volleyball after shoulder injury

The purpose of this study was to examine beach volleyball players’ experience regarding shoulder injury and how it affects their return to play. To achieve the research aims a qualitative design with semi-structured interviews had been conducted, five elite beach volleyball players, four men and one woman aged 27–42 participated in the study. All participants had suffered a severe shoulder injury, with absence from training and competing for at least 28 days. The findings of this study indicate that it is the individual’s inner motivation, together with a clear goal and support from the community, family, teammate and coach that are the most important factors when going through rehabilitation and getting back to playing beach volleyball after a shoulder injury. All participants had been affected by their injury in some way; some of the participants had been affected in a positive way since they had become mentally stronger and had developed better volleyball technique after rehabilitation. The conclusions of this study indicate that there are three distinct factors that increase the chances of getting back to playing beach volleyball after shoulder injury; it is the players’ self motivation, together with a clear goal and support from the community.

Injury profile among elite male youth soccer players in a Swedish first league

This study investigated the injury profile among elite male youth soccer players in a Swedish first league during two seasons. The present cohort study is based on data collected during the 2013–2014 seasons. In total, 43 young elite male soccer players, aged 15 to 19 yr, were prospectively followed regarding injuries, time of exposure, injury location, type of injury, and injury severity. The overall incidence of injury in the present study was estimated to 6.8 injuries per 1,000 exposure hours and 15.5 and 5.6 injuries per 1,000 hr for matches and training, respectively. The single most common injury subtype was muscle strain (53%). The hip and groin were the most common locations for injuries. Thirty-one percent of the injuries were classified as severe injury and caused >28 days absence from training and match play. Both the injury incidence and the number of serious injury seems to be relatively high in youth elite players according to this study. Although the injury incidence seems to be slightly lower than in adult elite players the injuries seem to be more traumatic in youth elite players.

Test-retest reliability of repeated knee laxity measurements in the acute phase following a knee trauma using a Rolimeter

The purpose was to examine the test-retest reliability of the Rolimeter measurement procedure in the acute time phase, following a substantial knee trauma. In total, 15 participants with acute knee trauma were examined by one single observer at three different time-points with the Rolimeter using a maximum force. The selected time-points were: baseline (0–7 days after the trauma), midpoint (3–4 weeks after the trauma), and endpoint (3–4 weeks after the trauma). The anterior-posterior displacement was recorded where the endpoint evaluation was used as the reference value. The mean anterior laxity scores remained constant over the measurement time-points for both knees, with an anterior laxity that was 2.7 mm higher (on average) in the injured than the noninjured knee (9.5 mm vs. 6.8 mm). The mean difference (i.e., bias) between laxity scores, for the injured knee, measured at endpoint versus baseline was 0.2±1.0 mm and −0.2±1.1 mm when measured at endpoint versus midpoint, with average typical errors of 0.7 and 0.8 mm and intra-class correlations that were very strong (both r=~0.93). For the same comparisons on the noninjured knee, systematic bias was close to zero (0.1±0.3 and −0.1±0.3 mm, respectively), and both the intra-class correlations were almost perfect (r=~0.99). The current study implicates that repeated Rolimeter measurements are relatively reliable for quantifying anterior knee laxity during the acute time-phases following knee trauma. Hence, the Rolimeter, in combination with manual tests, seems to be a valuable tool for identifying anterior cruciate ligament injuries.

The effects of introducing Tabata interval training and stability exercises to school children as a school-based intervention program

Abstract Background Physical activities during leisure time as well as school hours have changed over the past few years, with adolescents being less physically active and adopting a sedentary lifestyle. Objective The overall objective of this mixed-methods study was to evaluate the feasibility of introducing a 4-min Tabata interval training into a lower secondary school context. A further aim was to evaluate the possible effects on: coordination, balance, and strength. Methods The study was conducted as an intervention study with a mixed-method approach. Forty-three children, aged 7–9 years, participated in the intervention group. Additionally, 13 children were recruited as a control group. The intervention itself was delivered by the teachers and was performed for 4-min every day in a classroom setting. All participants performed physical tests before and after the intervention period to evaluate the Tabata training. After the completion of the 6-week Tabata interval training, the four teachers were interviewed. Results The push-ups (p = 0.004), kneeling push-ups (p = 0.03), and standing long jump (p = 0.01) improved in the intervention group after 6 weeks. No differences were observed between the genders. The teachers experienced that it worked well to integrate the Tabata interval training in the classroom setting. Conclusion After 6 weeks, a school-based Tabata intervention program improved physical performance. The teachers saw no obstacles in including the Tabata intervention program in a classroom setting and pointed out several positive aspects such as an increased energy level and development in the children’s movement patterns.