bluuebunny/crossref_metadata_2025 huggingface dataset:
Sports injuries in school‐aged children: A Studyd of traumatologic and socioeconomic outcome
Authors: Sørensen L. , Larsen S. E. , Röck N. D.
Published: July 2010

In this Danish study we attempted to identify the socioeconomic consequences of sports injuries in childre. A total of 1320 children, 650 boys and 670 girls, aged 6–17, completed questionnaires covering the period from the injury to recovery. The incidence rate was 74 per 1000 per year. The hospitalization rate was 4.1%. Due to the injury 37.2% of the children were absent from school for an average of 1.2 days (range 0–60 days), resulting in 1598 days’ absence from school. Most of the children were injured during training (34.7%) or competition (22.6%). The other injuries occurred durin recreational sporting activities (32.0%) or at school (10.7%). Fifty‐four percent were absent from work, on average for 2.2 days. Two hundred and nineteen children were absent from an after‐school job, for an average of 8.6 days. The total loss was 1896 working days. training or games, on average 6.0 times (range 0–99), with a total loss of 7897 training sesions. Fiften percent of the percent of the parents wre absent from work, on average for 2.2 days. Two hundred aqn nineten children wer absent from an afterschool job, for an average of 8.6 days. The total low was 1896 working day. The study shows that the socioenconomic consequences of sports injuries in children are a complex consisting of different parts and that the ijuries had a substantial impact on the functional and social status of the children and their families.
Multidirectional hyperlaxity of the shoulder: Results of treatment
Authors: Tillander B. , Lysholm M. , Norlin R.
Published: July 2010

We have evaluated the results after rehabilitation and compared this to inferior capsular shift in patients with multidirectional hyperlaxity (MDH). The patients (n=35) experienced either instability and/or pain. We divided the patients into two groups: one group (group A) included patients with MDH and only pain but no symptoms of instability (n=6). All these patients had initial rehabilitation, followed by surgery in four cases. None of the patients with only pain (n=6) were satisfied after rehabilitation. Only two out of four were satisfied after surgery. In the second group (group B) were included patients who had MDH with both pain and instability. Six patients had surgery without prior rehabilitation and 20 patients had initial rehabilitation. Eight of these patients had surgical stabilization after unsuccessful rehabilitation. Less than half of the patients with MDH and instability (n=20) were satisfied after rehabilitation alone. Twelve of 14 patients were satisfied after surgery. We conclude that patients with MDH and only pain are difficult to treat. Patients with MDH and instability respond only moderately to the exercise program. Surgery, in combination with physiotherapy, should be the initial treatment when instability is the main symptom.
Knee injury and Osteoarthritis Outcome Score (KOOS) ‐ validation of a Swedish version
Authors: Roos E. M. , Roos H. P. , Ekdahl C. , Lohmander L. S.
Published: July 2010

The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self‐administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form‐36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.
One‐leg standing balance and sports activity
Authors: Hahn T. , Foldspang A. , Vestergaard E. , Ingemann‐Hansen T.
Published: July 2010

The objective of the present cross‐sectional study was to estimate one‐leg standing balance in athletes and to investigate the relationship with type and amount of sports activity. The study comprised 339 active, competitive, non‐pregnant athletes, aged 14–24 years from two sports clubs in the county of Aarhus, Denmark. The athletes answered a questionnaire about occupation and sports activity. One‐leg standing balance was measured as the maximum time of one‐legged balancing. The mean of the maximum time of one‐legged balancing was 29 s (interquartile range 11.25–33.5 s). One‐leg standing balance was positively associated with years of participation in basketball and was not associated with sex and age. We conclude that participation in basketball may induce significantly adaptive effects on standing balance.
Supplement use and nutritional habits in Norwegian elite athletes
Authors: Ronsen O. , Sundgot‐Borgen J. , Maehlum S.
Published: July 2010

The purpose of this study was to examine nutritional and supplemental habits among international alpine‐ and cross‐country skiers and power sport athletes in Norway. Data from all the athletes of the National alpine skiing team (ALP: n= 33, 19 men and 14 women) and the National cross‐country skiing team (CRO: n= 34, 17 men and 17 women) plus a mixed group of power sport athletes (POW: n= 33, all men) from the National Feanis of boxers, weightlifters and track and field athletes, were collected through a semi‐structured interview during their annual medical examination. Twenty percent of all the athletes reported unsatisfactory nutritional habits (CRO 6%, ALP 27% and POW 27%: CRO vs. ALP/POW P<0.05). Eighty‐four percent used one or more micronutrient supplement (ALP 70%, POW 88%, CRO 95%: ALP vs. CRO/POW P<0.01). Power sport athletes had the most frequent use of supplemental creatine (45%), proteins/amino acids (30%), vitamins (88%) and minerals (82%), and CRO had the most frequent intake of iron (94%), vitamin C (88%) and fish oils (91%). Among ALP, only 7%, of the female athletes supplemented iron regularly compared to 37% of male ALP (P<0.05) Overall, male athletes supplemented mostly on a regular basis and female athletes more on an occasional basis. The results show that in spite of differences between sport groups, many elite athletes report unsatisfactory nutritional habits. Micronutrient supplementation was prevalent, but varied between both groups of sports and gender.
Prevention of injuries in young female players in European team handball. A prospective intervention study
Authors: Wedderkopp N. , Kaltoft M. , Lundgaard B. , Rosendahl M. , Froberg K.
Published: July 2010

Young female players in European handball have a very high injury incidence, up to 50 injuries per 1000 hours of game. More than half of these injuries happen without any external cause. The aim of the study was to investigate the effect of an intervention programme designed to reduce the number of injuries in young female players in European handball, with special emphasis on injuries in the lower extremities. The programme was created using elite athlete training programmes and those designed for rehabilitation of injured athletes with functional instability of their ankles and rupture of the anterior cruciate ligament. It included the use of an ankle disk for 10–15 min at all practice sessions, for one 10‐month season (August 1995‐May 1996). Twenty‐two teams participated in the study, and were randomly assigned to the intervention or control group. Eleven teams with 111 players were randomised to the intervention group and 11 teams with 126 players to the control group. Data were analysed using a t‐test for continuous variables, chi2‐analysis and Fisher's exact test for dichotomous variables and multivariate methods to determine odds‐ratios. The results indicated that using the intervention programme decreased the numbers of both traumatic and overuse injuries significantly. The differences in injuries between the groups were 80% during games and 71% during practice. In addition, the players in the control group had a 5.9 times higher risk of acquiring an injury than the players in the intervention group.
Jumper's knee
Authors: Fredberg U. , Bolvig L.
Published: July 2010

Jumper's knee is an overuse disease. The initial subjective complaints are well‐localized pain, usually occurring after physical activities and often at the lower pole of the patella. The diagnosis of jumper's knee is usually easily established after acquiring a detailed history and a carefully performed physical examination, but the lesion can be mistaken for other disorders or injuries, such as bursitis, meniscal injuries or chondromalacia (1) or other causes of the patellofemoral pain syndrome. Today ultrasonography is the method of choice for the evaluation of jumper's knee as it is both time and cost saving, non‐invasive, repeatable, accurate and allows a dynamic image of the tendon, guided injections and control of treatment. Conservative therapy is the treatment of choice in the early stages and includes adequate warm‐up, stretching of the quadriceps muscle and physical activity with respect to the pain, and ice pack application after activity. When the pain disappears, the training intensity can be increased. NSAID (Non‐Steroidal Anti‐Inflammatory Drugs) and local peritendinous injections with long‐acting steroids can be a helpful and safe adjuvant to the conservative treatment and should be tried before surgery. Surgical treatment is indicated only if a prolonged and well‐supervised conservative treatment program fails in chronic jumper's knee (including local injection with steroid) or in acute total rupture. Review papers concerning jumper's knee are already published (2–5), but in this review the importance of ultrasonography to make the diagnosis, to plan therapy and control the treatment and the safety of peritendinous injection with steroid is pointed out. The scientific documentation for the recommanded treatment (conservative, steroid injection and operation) is, however, insufficient. Many more controlled studies are needed. Ultrasonography and placebo‐controlled, double–blinded, cross‐over studies for treatment with local injection of steroid are ongoing (6, 7).
Glycogen concentration in human skeletal muscle: effect of prolonged insulin and glucose infusion
Authors: Hansen B. F. , Asp S. , Kim B. , Richter E. A.
Published: July 2010

To study the upper limit of glycogen storage in human muscle, two healthy male subjects were infused with glucose and insulin for 8 h reaching plasma concentrations of about 21 mM glucose and approximately 2000 μU/ml insulin. Prior to the infusion subjects performed for 1 h one‐legged knee‐extensor exercise at 75% of their maximum one‐legged work capacity in order to lower muscle glycogen stores in one leg. During the 8‐h hyperglycemic clamp procedure, glycogen concentrations increased and levelled off at 2‐ and 5‐fold above the pre‐infusion levels in the resting and the working leg, respectively. However, the absolute glycogen levels reached in both legs were quite similar, close to 4 g per 100 g wet muscle (about 1000 μmol/g d.w.), independent of prior exercise. Previous studies have shown that glycogen levels, after a bout of glycogen‐depleting exercise and subsequent ingestion of a carbohydrate‐rich diet for 3 days, can be increased to values around 3–4 g per 100 g wet muscle. It appears that the maximal attainable glycogen concentration in human muscle seems to be close to 4 g per 100 g wet muscle. This glycogen level can thus be reached either by a prolonged infusion of supra‐physiological concentrations of glucose and insulin or by glycogen‐depleting exercise followed by ingestion of a carbohydrate‐rich diet.
Comparison of arthroscopic one‐incision and two‐incision techniques for reconstruction of the anterior cruciate ligament
Authors: Karlsson J. , Kartus J. , Brandson S. , Magnusson L. , Lundin O. , Eriksson B. I.
Published: July 2010

The purpose of this study was to assess the outcome of arthroscopic anterior cruciate ligament reconstruction performed using either the ‘one‐incision’ technique or the rear‐entry ‘two‐incision’ technique. A series of 221 consecutive patients who underwent anterior cruciate ligament reconstruction was reviewed retrospectively. In the study population, two subgroups were defined. Group A consisted of 118 patients who underwent reconstruction using the one‐incision transtibial endoscopic technique and Group B consisted of 103 patients who underwent reconstruction using the two‐incision technique. The groups were comparable in terms of age, sex and activity level. The follow‐up was performed after 47 (40–68) months in Group A and 55 (40–68) months in Group B. The Lysholm score at the final follow‐up was significantly lower in Group A (90, 38–100) than in Group B (94, 34–100) (P=0.002). The median KT‐1000 total side‐to‐side difference was 1.5 (‐6 to 7.5) mm in Group A, and 2.0 (‐3.5 to 9) mm in Group B (n.s.). No significant difference between the groups was found when the IKDC evaluation system was used. Four intra‐operative complications were registered in Group A and none in Group B (P=0.06). No significant difference was found in terms of anterior knee pain, the one‐leg‐hop quotient or the activity level at the final follow‐up. In this study the two methods gave similar and satisfactory results. Serious intra‐operative complications were, however, recorded in four cases when the one‐incision technique was used.
Arterial haemoglobin oxygen saturation is affected by F1O2 at submaximal running velocities in elite athletes
Authors: Peltonen J. E. , Leppävuori A. P. , Kyrö K. ‐P. , Mäkelä P. , Rusko H. K.
Published: July 2010

This study was conducted to determine whether arterial desaturation would occur at submaximal workloads in highly trained endurance athletes and whether saturation is affected by the fraction of oxygen in inspired air (F1O2). Six highly trained endurance athletes (5 women and 1 man, aged 25 ± 4 yr, VO2max 71.3 ± 5.0 ml · kg−1· min−1) ran 4 × 4 min on a treadmill in normoxia (F1O2 0.209), hypoxia (F1O2 0.155) and hyperoxia (F1O2 0.293) in a randomized order. The running velocities corresponded to 50, 60, 70 and 80% of their normoxic maximal oxygen uptake (VO2max). In hypoxia, the arterial haemoglobin oxygen saturation percentage (SpO2%) was significantly lower than in hyperoxia and normoxia throughout the test, and the difference became more evident with increasing running intensity. In hyperoxia, the Sp2% was significantly higher than in normoxia at 70% running intensity as well as during recovery. The lowest values of SpO2% were 94.0±3.8% (P<0.05, compared with rest) in hyperoxia, 91.0±3.6% (P<0.001) in normoxia and 72.8 ± 10.2% (P<0.001) in hypoxia. Although the SpO2% varied with the F1O2, the VO2 was very similar between the trials, but the blood lactate concentration was elevated in hypoxia and decreased in hyperoxia at the 70% and 80% workloads. In conclusion, elite endurance athletes may show an F1O2‐dependent limitation for arterial O2 saturation even at submaximal running intensities. In hyperoxia and normoxia, the desaturation is partly transient, but in hypoxia the desaturation worsens parallel with the increase in exercise intensity.
Sports and risk for severe osteoarthrosis of the knee
Authors: Sandmark H. , Vingård E.
Published: July 2010

The relationship between sports activities and knee osteoarthrosis (OA) in the general population was investigated. Men (n=325) and women (n=300) who underwent prosthetic surgery due to primary tibio‐femoral OA were compared with referents (264 men and 284 women) regarding life‐long sports exposure. The relative risk of severe knee OA among men aged between 55 and 65 years who were highly exposed to all kinds of sports was 2.9 (95% CI 1.3–6.5). For sports such as cross‐country skiing, soccer and ice hockey/bandy, the relative risk was higher for those men who had been exposed. The women had only been active in sports to a limited extent, and no increased relative risk was found. Moderate daily general physical activity was not found to be a risk factor.
A comparison of results after arthroscopic anterior cruciate ligament reconstruction in female and male competitive athletes A two‐ to five‐year follow‐up of 429 patients
Authors: Wiger P. , Brandsson S. , Kartus J. , Eriksson B. I. , Karlsson J.
Published: July 2010

The aim of this study was to compare the results after arthroscopic anterior cruciate ligament reconstruction in female and male competitive athletes who had a pre‐injury Tegner activity level of ≥7 and a non‐injured contralateral anterior cruciate ligament. One hundred and thirty‐three female and 296 male patients were followed at 38 (21–68) months after the index operation. All the patients were operated on by experienced knee surgeons using patellar tendon autografts and interference screw fixation. At the index operation the median age of the female patients was 23 (16–45) years and the median age of the male patients was 26 (16–47) years. The reconstruction was performed a median of 10 (0–141) and 10 (0–203) months after the injury in women and men respectively. The patients were re‐examined by independent observers. At the follow‐up, the median Lysholm score was 89 (38–100) points in the female group and 90 (22–100) points in the male group (P=0.015). The IKDC evaluation system, subjective anterior knee pain, subjective evaluation of the results, the knee‐walking test and the KT‐1000 tests revealed no differences between the groups. The mean (±2 SD) pre‐injury Tegner activity level was 8.1 (±1.9) (median 8 (7–10)) in the female group and 8.4 (±1.8) (median 9 (7–10)) in the male group (P=0.003). At the follow‐up, the Tegner activity level was 6.2 (±3.8) in the female group and 6.8 (±3.6) in the male group (P=0.012). At the follow‐up, the Tegner activity level had decreased by 1.9 (±3.8) for the women and 1.6 (±3.3) for the men, as compared with the pre‐injury level (n.s.). The difference between the performed and the desired activity level at the follow‐up was 1.1 (±3.2) in the female group and 0.9 (±3.0) in the male group (n.s.). In the female group 53/133 (40%) and in the male group 115/296 (39%) returned to the pre‐injury activity level (n.s.). The median one‐leg‐hop quotient was 93 (0–116)% in the female group and 96 (0–130)% in the male group (P=0.006). Concomitant meniscal injuries prior to the index operation, at the index operation or during the follow‐up period were found in 64/133 (48%) women and in 185/296 (62%) men (P<0.01). The main conclusion was that the overall results in female and male athletes were comparable two to five years after the anterior cruciate ligament reconstruction. However, concomitant meniscal injuries were more common in male than females athletes after anterior cruciate ligament injuries.
Predicting physical activity intentions using a goal perspectives approach: a study of Hungarian youth
Authors: Biddle S. J. H. , Seos I. , Chatzisarantis N.
Published: July 2010

Utilising a goal perspectives framework, a study predicting physical activity intentions in 12 to 16‐year‐old Hungarian adolescents was conducted with two samples. Theoretical predictions established a model that was tested through path analysis. Beliefs thought to underpin goal orientations were hypothesised to predict ego orientation (general and gift beliefs) and task orientation (learning and incremental beliefs). Task orientation was hypothesised to predict intentions directly, while ego orientation was hypothesised to predict intentions indirectly through perceived competence. Results from the first sample (n= 301) suggested that the model could be improved by adding paths between general beliefs and perceived competence and between task orientation and perceived competence. This modified model was shown to fit data from a second sample (n= 422) very well. Multi‐group analysis confirmed a good fit and so the two samples were combined. The model fitted the data well for the total sample (n= 723). Overall, results showed that 20.8% of the variance in intentions was explained by the model, and that sport ability beliefs were moderately associated with task orientation but only weakly associated with ego orientation. The motivational importance of a task orientation was confirmed with its direct prediction of intentions.
Relationship between achievement goal orientations and perceived motivational climate on intrinsic motivation
Authors: Brunel P. C.
Published: July 2010

This study examines first the relationship of perceived motivational climate and goal orientation to indices of intrinsic, extrinsic motivation and a motivation, and second their respective role in predicting these indices of motivation. A total of 160 students enrolled in physical activity classes volunteered to participate. Results of Pearson correlation analyses indicated that students who perceived their class climate as emphasizing mastery were more likely to feel self‐determined. Hierarchical regression analyses revealed that perceived motivational climate was a better predictor of all indices of motivation than goal orientations. Results, discussed according to the achievement goal perspective and the hierarchical model of intrinsic and extrinsic motivation, highlight a possible motivational process explaining how the motivational climate overrides goal orientations.
Meniscal substitutes – animal experience
Authors: Kohn D. , Verdonk R. , Aagaard H. , Sell R. , Dienst M.
Published: July 2010

Animal studies have shown that meniscus allografts and tendon autografts generally heal to the capsule, are revascularized and repopulated with host cells. In animals, neither meniscal allografts nor tendon or fat autografts gain the properties of a normal meniscus. Meniscus allografts and tendon autografts are promising as both seem to offer some protection to the cartilage of the tibial plateau. There is no evidence that meniscal transplantation can prevent cartilage degenerative changes, and the long‐term effect of meniscal transplantation on articular cartilage remains unknown. Whether cellular repopulation of the meniscal allograft is sufficient to restore its biomechanical properties is unknown. Collagen scaffolds and tissue engineered grafts are still under investigation, showing promising results especially for the former. Viable meniscal allografts should be implanted within 1 to 2 weeks after harvesting, as the production of proteoglycans decreases after 2 weeks.
Harvest and conservation of meniscal allografts
Authors: Verdonk R. , Kohn D.
Published: July 2010

Meniscal allografts can be harvested and preserved in different ways. A technique for harvesting and conserving viable allografts is described. The meniscus should be harvested within 12 h after the start of ischaemia. The ideal time for implantation of the viable graft is 10 to 14 days after harvest, in which time a recipient should be identified. Frozen grafts are avital. Cryopreserved grafts are not avital, as 10–30% of the fibrochondrocytes are preserved. Frozen and cryopreserved grafts can be stored for a long time and if a graft bank is established, grafts are always readily available. There is no proven advantage of one graft type over others.
Meniscus transplantation: Preoperative planning
Authors: Verdonk R. , Kohn D.
Published: July 2010

Precise preoperative planning is mandatory to obtain good results of meniscus transplantation. Any pathology in addition to the missing meniscus should be detected, including malalignment, and ligament instability. A full status of the changes in the cartilage should be made. It is unknown how precisely the donor meniscus needs to fit the size of the original meniscus to allow healing and regeneration. The effect of incongruency and wrong insertion of the meniscal horns has been investigated in an animal experiment. The incongruous grafts did not entirely avoid chondromalacia after meniscectomy, but provided some chondroprotective effect. A wrong bony insertion of the meniscal horns leads to even more serious chondral damage than meniscectomy.
Arthroscopic and open surgical techniques for meniscus replacement – meniscal allograft transplantation and tendon autograft transplantation
Authors: Goble E. M. , Verdonk R. , Kohn D.
Published: July 2010

Open, arthroscopically assisted and arthroscopic methods for lateral and medial meniscus allograft transplantation with bone plug fixation are described. An open technique for medial and lateral meniscus transplantation without bone plug fixation, as well as an open technique for autograft quadriceps tendon replacement of the medial meniscus are described.
Future research in meniscal replacement
Authors: Messner K. , Kohn D. , Verdonk R.
Published: July 2010

To study the remodelling process after meniscus replacement and to learn how to control it will be a key topic for future research. Not enough is known about the importance of precision in meniscal fixation and how to make the insertions as strong as in the normal meniscus. Methods to measure load‐distribution, mechanical properties of the graft and status of the cartilage should be developed. A number of different auto‐ and allografts have been shown to heal and revascularize, but whether the grafts are functioning is not known. Meniscal scaffolds, which can be used for replacement of partial meniscal loss, need to be tested. Scaffolds and tissue engineering will be the subject of intensive research in the future.
Comparison of saccadic eye movements and facility of ocular accommodation in female volleyball players and non‐players
Authors: Jafarzadehpur E. , Aazami N. , Bolouri B.
Published: July 2010

There is controversy on the interaction of sport exercise and visual functions. Some aspects of visual skills have been evaluated in volleyball players.

Eighty‐three normal females were categorized in four groups; non‐players (NP), beginner volleyball players, intermediate and advanced players. Facility of accommodation and far saccade for optotypes at three distances were measured.

The athletes showed better facility of accommodation and saccadic eye movement (SEM) than the non‐playing control group. There was a significant difference (P<0.001) between NP and beginner players with advanced players and intermediate players.

There are mutual interrelations between the visual system and sensory‐motor coordination of the whole body. In a “programed” activity many motor and sensorial elements interactively influence one another. The visual system, as the most important coordinator, navigates the “programed” activities. The facility of accommodation shows how fast clear vision can be accomplished. The SEM shows how fast visual system can fixate on an object. Improvement of these two parameters indicates that the visual system can change fixation very fast and clearly see a new fixation point promptly. These are the requirement for a good volleyball player; hence, we find better visual performance in advanced players than in others.
Dynamic trunk stability is improved in paraplegics following kayak ergometer training
Authors: Bjerkefors A. , Carpenter M. G. , Thorstensson A.
Published: July 2010

The purpose of the study was to assess whether postural stability in persons with spinal cord injury (SCI) could be affected by training. Ten post‐rehabilitated persons with thoracic SCI performed 30 sessions of kayak ergometer training during a 10‐week period. The ergometer was modified with a balance module adjustable in the medio‐lateral direction. Before and after the training period, horizontal support‐surface translations were presented randomly, either in the forward or backward direction, or to the side, while subjects sat in their own wheelchairs. The platform perturbation consisted of an unpredictable initial acceleration, followed by a constant‐velocity phase and a predictable deceleration. Markers were applied on the trunk and movement data were recorded in 3D. Four kinematic responses of trunk angular and linear displacement were investigated. In general, postural stability was improved after training with smaller rotational and linear displacements of the trunk observed during both predictable and unpredictable translations in all directions. Thus, the training was able to improve the ability of persons with long‐standing SCI to maintain an upright sitting posture in response to externally generated balance perturbations, which should imply an increased capacity to master similar challenges to balance in everyday life.
A comparison of sprinting kinematics on two types of treadmill and over‐ground
Authors: McKenna M. , Riches P. E.
Published: July 2010

Conventionally motorized treadmills elicit different sprinting kinematics to the over‐ground condition. Treadmills powered by a torque motor have been used to assess sprinting power; yet, the kinematics of sprinting on the torque treadmill are unknown. This study compares the sprinting kinematics, during the constant velocity phase, between a conventional treadmill, a torque treadmill and the over‐ground condition to assess the suitability of each treadmill for sprinting studies and training. After familiarization, 13 recreationally active males performed multiple sprints at various experimental settings on each surface. Ninety sprints, which attained mean velocities over 7.0 m/s, had their lower‐body sagittal plane joint angles during ground contact captured at 250 Hz. These data were low‐pass filtered at 10 Hz, and compared with respect to surface, subject and velocity using an ANCOVA statistical model. Sprinting on the conventional treadmill elicited a longer ground contact time, a longer braking phase, a more extended knee at foot strike and a faster extending hip than the torque treadmill and over‐ground (all P<0.05). The torque treadmill obtained an equivalent sprinting technique to the over‐ground condition, with the exception of a less extended hip at toe‐off, suggesting that it is more appropriate for laboratory sprinting analyses and training than the conventional treadmill.
Physical benefits of expanded physical education in primary school: findings from a 3‐year intervention study in Sweden
Authors: Sollerhed A.‐C. , Ejlertsson G.
Published: July 2010

The aim of this study was to assess whether a school‐based program with expanded physical education lessons was effective in increasing children's physical capacity and in preventing excessive weight gain in children. The study performed in 2000–2003 comprised 132 children, 73 boys and 59 girls at baseline 6–9 years and in follow‐up 9–12 years, attending two different schools with a similar size, appearance and structure in a rural area. The norm school (N‐school) followed the stipulated curricular time, one to two physical education lessons a week, while the intervention school (I‐school) increased it to four lessons. More positive changes in physical index (the sum of the age‐standardized results in 11 physical tests) were found among children in the I‐school than in the N‐school. The number of children who increased body mass index (BMI) increased in both schools, but a lower increase in BMI could be seen in the I‐school. Expanded physical education lessons could increase physical status among both overweight and normal‐weight children, in particular aerobic fitness. The weekly dose of physical activity must be higher than 40 min a day and must start earlier in children's life to be more effective in combating BMI increase.
A social cognitive approach to burnout in elite athletes
Authors: Lemyre P.‐N. , Hall H. K. , Roberts G. C.
Published: July 2010

The purpose of this study was to investigate athlete burnout from a social‐cognitive perspective by examining the relationship between social cognitive motivational variables at the start of a season and signs of burnout in elite athletes at the end of the season. Participants were 141 (F=60, M=81) elite winter sport athletes competing in Alpine skiing, Biathlon, Nordic Combined, Nordic skiing, and Speed skating. Participants completed a comprehensive motivation assessment package at the start of the season and a further burnout inventory at season's end. Results indicated that motivational dispositions, measures of the achievement climate, perceived ability and dimensions of perfectionism were associated with burnout in a conceptually consistent manner. Furthermore, the elite athletes could be grouped into two motivational profiles based on variables measured at the start of the season, one being adaptive and the other maladaptive. At season's end, the two different motivational profiles yielded distinctively different responses on an inventory assessing signs of burnout. The current findings strengthen the claim that burnout in elite athletes may not simply be “motivation gone awry” as Gould has suggested, but an inevitable consequence of exhibiting a maladaptive motivational profile.
ST/G ACL reconstruction: double strand plus extra‐articular sling vs double bundle, randomized study at 3‐year follow‐up
Authors: Zaffagnini S. , Bruni D. , Russo A. , Takazawa Y. , Lo Presti M. , Giordano G. , Marcacci M.
Published: July 2010

Several investigators have reported the presence of biomechanical, kinematic, anatomic, fiber orientation patterns and biological differences between the anteromedial bundle and the posterolateral bundle of ACL. The purpose of this prospective randomized study was to compare the clinical, instrumental and X‐ray outcome of two ACL reconstruction techniques with hamstring tendons: one with a single intra‐articular bundle associated to an extra‐articular sling, the second with a more anatomic double‐bundle technique that reproduces better the native ACL function. From an initial group of 100 patients who underwent ACL reconstruction, 72 patients (35 single bundle plus lateral plasty and 37 double bundle) were evaluated with IKDC, Tegner score, KT2000 arthrometer, Activity Rating Scale, Psychovitality Questionnaire and Ahlback radiographic score at a mean 3 years follow‐up. Double‐bundle group showed significantly better results regarding IKDC, ROM, Activity Rating Scale and time to return to sport. Also KT 2000 showed significant differences in objective stability. The double‐bundle technique for ACL reconstruction described in this paper has demonstrated significantly better subjective, objective and functional results compared with a double‐stranded hamstrings plus extra‐articular sling at a minimum 3‐year follow‐up.
The Enduro motorcyclist's wrist and other overuse injuries in competitive Enduro motorcyclists: a prospective study
Authors: Sabeti‐Aschraf M. , Serek M. , Pachtner T. , Auner K. , Machinek M. , Geisler M. , Goll A.
Published: July 2010

According to public opinion, Enduro motorcycling is a dangerous sport. Little is known about overuse injuries in connection with this sport. The study consisted of two phases. Phase 1 was planned as a prospective feasibility study for phase 2. The latter was initiated as a prospective investigation, comprising a random sample of the participants of phase 1. Enduro motorcyclists were interviewed with a prepared questionnaire. Clinical examinations were performed immediately before, and after, a major Enduro race, including pain assessment in the hand/wrist and the forearm using the visual analog scale. The occurrence of Raynaud's syndrome carpal tunnel syndrome (CTS), and loss of grip strength in the forearm muscles were recorded in detail. Phase 1 showed that the predominant overused anatomical regions were the hand/wrist and forearms. Nearly 50% of all the riders complained of pain or paresthetic sensations. A significant increase in pain was registered after the race. After the second run 32.28% of all riders had CTS in the left hand and 43.31% in the right hand. More than one‐half of the athletes complained of overuse injuries. Transient CTS is an overuse injury closely related to sports.
Perceived ability and social support as mediators of achievement motivation and performance anxiety
Authors: Abrahamsen F. E. , Roberts G. C. , Pensgaard A. M. , Ronglan L. T.
Published: July 2010

The present study is founded on achievement goal theory (AGT) and examines the relationship between motivation, social support and performance anxiety with team handball players (n=143) from 10 elite teams. Based on these theories and previous findings, the study has three purposes. First, it was predicted that the female athletes (n=69) would report more performance worries and more social support use than males (n=74). The findings support the hypothesis for anxiety, but not for social support use. However, females report that they felt social support was more available than males. Second, we predicted and found a positive relationship between the interaction of ego orientation and perceptions of a performance climate on performance anxiety, but only for females. As predicted, perceived ability mediated this relationship. Finally, we predicted that perceptions of a performance climate were related to the view that social support was less available especially for the male athletes. Simple correlation supports this prediction, but the regression analyses did not reach significance. Thus, we could not test for mediation of social support between motivational variables and anxiety. The results illustrate that fostering a mastery climate helps elite athletes tackle competitive pressure.
Performance aspects of an injury prevention program: a ten‐week intervention in adolescent female football players
Authors: Steffen K. , Bakka H. M. , Myklebust G. , Bahr R.
Published: July 2010

The injury rate in football is high, and effective injury prevention methods are needed. An exercise program, the “11,” has been designed to prevent the most common injury types in football. However, the effect of such a program on performance is not known. The aim of this randomized‐controlled trial was to investigate the effect of the “11” on performance after a 10‐week training period. Thirty‐four adolescent female football players were randomly assigned to either an intervention (n=18) or a control group (n=16). The “11” is a 15‐min program consisting of ten exercises for core stability, lower extremity strength, balance and agility. Performance tests included isokinetic and isometric strength protocols for the quadriceps and hamstrings, isometric hip adduction and abduction strength, vertical jump tests, sprint running and soccer skill tests. There was no difference between the intervention and control groups in the change in performance from the pre‐ to post‐test for any of the tests used. In conclusion, no effect was observed on a series of performance tests in a group of adolescent female football players using the “11” as a structured warm‐up program.
Acute fatigue‐induced changes in muscle mechanical properties and neuromuscular activity in elite handball players following a handball match
Authors: Thorlund J. B. , Michalsik L. B. , Madsen K. , Aagaard P.
Published: July 2010

The purpose of the present study was to determine the acute fatigue development in muscle mechanical properties and neuromuscular activity in response to handball match play. Male elite handball players (n= 10) were tested before and after a simulated handball match for maximal isometric strength [maximal voluntary contraction (MVC)] and rate of force development (RFD) with synchronous electromyography (EMG) recording, while maximal vertical jump parameters were assessed using force plate analysis. Quadriceps and hamstrings MVC and RFD decreased significantly post‐match (∼10%, P<0.05 and ∼16–21%, P<0.05, respectively). During quadriceps, MVC mean EMG amplitude [mean average voltage (MAV)] decreased for the vastus lateralis (VL) and rectus femoris (RF) (21–42%, P≤0.05), while MAV also decreased in the antagonist biceps femoris (BF) muscle (48–55%, P<0.01). During hamstring MVC, MAV was reduced in BF (31%, P<0.01). Maximum EMG amplitude during quadriceps MVC was reduced for the VL (28%, P<0.01) and the RF (5%, P<0.05). During hamstring MVC, maximum EMG was reduced for BF (21%, P<0.01). Post‐match maximal jump height was reduced (5.2%, P<0.01), as was also work (6.8%, P<0.01), velocity of center of mass (2.4–4.0%, P<0.01) and RFD (∼30%, P<0.05). In conclusion, maximal (MVC) and rapid muscle force characteristics (RFD, impulse) were acutely affected concurrently with marked reductions in muscle EMG following handball match play, which may potentially lead to impaired functional performance.
Influence of pacing strategy on O2 uptake and exercise tolerance
Authors: Jones A. M. , Wilkerson D. P. , Vanhatalo A. , Burnley M.
Published: July 2010

Seven male subjects completed cycle exercise bouts to the limit of tolerance on three occasions: (1) at a constant work rate (340±57 W; even‐pace strategy; ES); (2) at a work rate that was initially 10% lower than that in the ES trial but which then increased with time such that it was 10% above that in the ES trial after 120 s of exercise (slow‐start strategy; SS); and, (3) at a work rate that was initially 10% higher than that in the ES trial but which then decreased with time such that it was 10% below that in the ES trial after 120 s of exercise (fast‐start strategy; FS). The expected time to exhaustion predicted from the pre‐established power–time relationship was 120 s in all three conditions. However, the time to exhaustion was significantly greater (P<0.05) for the FS (174±56 s) compared with the ES (128±21 s) and SS (128±30 s) conditions. In the FS condition, V̇O2 increased more rapidly toward its peak such that the total O2 consumed in the first 120 s of exercise was greater (ES: 5.15±0.78; SS: 5.07±0.83; FS: 5.36±0.84 L; P<0.05 for FS vs ES and SS). These results suggest that a fast‐start pacing strategy might enhance exercise tolerance by increasing the oxidative contribution to energy turnover and hence “sparing” some of the finite anaerobic capacity across the transition to high‐intensity exercise.
Different hormonal response to continuous and intermittent exercise in middle‐distance and marathon runners
Authors: Vuorimaa T. , Ahotupa M. , Häkkinen K. , Vasankari T.
Published: July 2010

In order to study the effects of different athletic backgrounds on exercise‐induced hormonal responses, serum testosterone, luteinizing hormone, follicle‐stimulating hormone and cortisol concentrations were measured before and after intensive continuous and intermittent running in well‐trained middle‐distance runners (MID) and marathon runners (MAR). They performed two 40‐min exercises on a treadmill: a continuous run at an intensity of 80% [tempo run (TR)] and an intermittent run (IR) at an intensity of 100% of the velocity associated with VO2max. The testosterone response to IR and the cortisol response to TR was higher (P<0.05) in MID compared with MAR. The testosterone response to IR correlated positively with the maximal blood lactate concentration achieved after the maximal running test (r=0.46, P<0.05, n=20), while the cortisol response to TR correlated negatively with the runner's VO2max (r=−0.62, P<0.05, n=20). In conclusion, a continuous running exercise resulted in a lower cortisol response in runners who are adapted for longer distances, and an intermittent running exercise resulted in a higher testosterone response in runners who are adapted to middle distances.
Concurrent validity of the PAM accelerometer relative to the MTI Actigraph using oxygen consumption as a reference
Authors: Slootmaker S. M. , Chin A Paw M. J. M. , Schuit A. J. , Van Mechelen W. , Koppes L. L. J.
Published: July 2010

The purpose of this study was to examine the concurrent validity of the Personal Activity Monitor (PAM) accelerometer relative to the Actigraph accelerometer using oxygen consumption as a reference, and to assess the test–retest reliability of the PAM. Thirty‐two fit, normal weight adults (aged 21–54) performed two activities, treadmill walking and stair walking, while wearing the PAM, the Actigraph and the Cosmed K4b2. Correlation coefficients and agreement in absolute energy expenditure (EE) levels between PAM, Actigraph and Cosmed were calculated. The test–retest reliability was examined among 296 PAM's using a laboratory shaker. Intraclass correlation coefficients (ICC) and coefficient of variation (CV) were determined. Correlations for treadmill walking and stair walking, respectively, were r2=0.95 and r2=0.65 for PAM with Actigraph, r2=0.82 and r2=0.93 for PAM with VO2 and r2=0.64 and 0.74 for Actigraph with VO2. Both the PAM and Actigraph underestimated EE during treadmill and stair walking by a substantial amount. The test–retest reliability of the PAM was high [ICC=0.80; 95% confidence interval (CI) (0.28;0.92) and intra‐CV=1.5%]. The PAM and Actigraph accelerometer are comparable in assessing bodily movement during treadmill and stair walking. The PAM is a valid device to rank subjects in EE and can be useful in collecting objective data to monitor habitual physical activity.
Walking, vigorous physical activity, and markers of hemostasis and inflammation in healthy men and women
Authors: Hamer M. , Steptoe A.
Published: July 2010

The impact of walking on cardiovascular health, as compared with vigorous physical activity, remains controversial. We performed a cross‐sectional analysis including 185 healthy participants drawn from the Whitehall II epidemiological cohort to examine whether there is an independent association between walking and markers of hemostasis and inflammation after controlling for vigorous physical activity. Blood was drawn for the assessment of von Willebrand factor antigen (vWF), fibrinogen, interleukin (IL)‐6, IL‐1 receptor antagonist (IL‐1ra), and tumor necrosis factor‐α (TNF‐α). Self‐reported levels and types of physical activity were recorded, including time spent walking per week and frequency of participation in vigorous physical activity. Multiple linear regression analyses, adjusted for age, body mass index, blood pressure, gender, smoking, alcohol, grade of employment, and frequency of vigorous physical activity revealed that time spent walking was inversely related to vWF (β=−0.13, P=0.086), fibrinogen (β=−0.16, P=0.016), IL‐6 (β=−0.12, P=0.087), and TNF‐α (β=−0.16, P=0.039). In addition, vigorous activity was inversely associated with hemostatic markers but not with inflammatory cytokines. Regular walking is associated with lower levels of hemostatic and inflammatory markers independently of vigorous physical activity in healthy men and women.
Exploring the social image of anabolic steroids users through motivation, sportspersonship orientations and aggression
Authors: Chantal Y. , Soubranne R. , Brunel P. C.
Published: July 2010

The authors explored social perceptions related to the use of anabolic steroids (AS) in sports. More specifically, 78 women and 102 men read one of two scenarios depicting a male athlete facing either a drug use or non‐drug use situation. Then, participants reported their perceptions of the scenario protagonist in terms of self‐determined sport motivation, sportspersonship orientations, and athletic aggression. Results of a multivariate analysis of covariance indicated that, in comparison with a non‐using protagonist, the AS‐using athlete was regarded as less self‐determined in one's motivation (i.e., sport participation based on predominant feelings of pressure to obtain external rewards or avoid punishment) and as displaying weaker sportspersonship orientations (i.e., lesser concerns for opponents, the social conventions of sport, and for one's own athletic commitment). In addition, the AS‐using athlete was perceived as resorting more readily to reactive aggression than to instrumental aggression (i.e., intent to injure one's opponent vs merely hinder his performance). Finally, the analyses did not disclose significant gender or interaction effects. The findings are discussed in view of theoretical and practical implications.