| 1. |
- Andersson, Therese, et al.
(författare)
-
Growth hormone does not stimulate early healing in rat tendons
- 2012
-
Ingår i: International Journal of Sports Medicine. - Stuttgart : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 33:3, s. 240-243
-
Tidskriftsartikel (refereegranskat)abstract
- Growth Hormone stimulates bone growth and fracture repair. It acts mainly by increasing the systemic levels of IGF-1. Local treatment with IGF-1 appears to stimulate tendon healing. We therefore hypothesized that systemic treatment with Growth Hormone would also stimulate tendon healing. Rat Achilles tendons were transected and left to heal. 4 groups were studied. Intramuscular injections of botulinum toxin A (Botox) were used to reduce loading in 2 groups. The animals were randomized to twice daily injections of Growth Hormone (n=2×10) or saline (n=2×10), and killed after 10 days. Healing was assessed by mechanical testing. Muscle paralysis induced by Botox reduced the strength of the healing tendon by two thirds. Growth Hormone increased femoral and tibial length in the unloaded, and femoral and tibial weight in the loaded group. Body weight and muscle weight were increased in both. In contrast, there was no increase in the strength of the healing tendons, regardless of mechanical loading status. An increase in peak force of the loaded healing tendons by more than 5% could be excluded with 95% confidence. In spite of its stimulatory effects on other tissues, Growth Hormone did not appear to stimulate tendon or tendon repair.
|
|
| 2. |
- Artero, EG, et al.
(författare)
-
Reliability of field-based fitness tests in youth
- 2011
-
Ingår i: International journal of sports medicine. - : Georg Thieme Verlag KG. - 1439-3964 .- 0172-4622. ; 32:3, s. 159-169
-
Tidskriftsartikel (refereegranskat)
|
|
| 3. |
|
|
| 4. |
- Balsom, Paul, et al.
(författare)
-
Maximal-Intensity Intermittent Exercise: Effect of Recovery Duration
- 1992
-
Ingår i: International Journal of Sports Medicine. - 0172-4622 .- 1439-3964. ; 13:7, s. 528-533
-
Tidskriftsartikel (refereegranskat)abstract
- Seven male subjects performed 15 x 40m sprints, on three occasions, with rest periods of either 120 s (R120), 60 s (R60) or 30 s (R30) between each sprint. Sprint times were recorded with four photo cells placed at 0, 15, 30 and 40 m. The performance data indicated that whereas running speed over the last 10 m of each sprint decreased in all three protocols (after 11 sprints in R120, 7 sprints in R60 and 3 sprints in R30), performance during the initial acceleration period from 0-15 m was only affected with the shortest rest periods increasing from (mean +/- SEM) 2.58 +/- .03 (sprint 1) to 2.78 +/- .04 s (spring 15) (p < .05). Post-exercise blood lactate concentration was not significantly different in R120 (12.1 +/- 1.3 mmol.l-1) and R60 (13.9 +/- 1.2 mmol.l-1), but a higher concentration was found in R30 (17.2 +/- .7 mmol.l-1) (p < .05). After 6 sprints there was no significant difference in blood lactate concentration with the different recovery durations, however, there were significant differences in sprint times at this point, suggesting that blood lactate is a poor predictor of performance during this type of exercise. Although the work bouts could be classified primarily as anaerobic exercise, oxygen uptake measured during rest periods increased to 52, 57 and 66% of maximum oxygen uptake in R120, R60 and R30, respectively. Evidence of adenine nucleotide degradation was provided by plasma hypoxanthine and uric acid concentrations elevated post-exercise in all three protocols. Post-exercise uric acid concentration was not significantly affected by recovery duration.(ABSTRACT TRUNCATED AT 250 WORDS)
|
|
| 5. |
|
|
| 6. |
- Baumeister, J., et al.
(författare)
-
Brain Activity in Predictive Sensorimotor Control for Landings: an EEG Pilot Study
- 2013
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 34:12, s. 1106-1111
-
Tidskriftsartikel (refereegranskat)abstract
- Landing from a jump is related to predictive sensorimotor control. Frontal, central and parietal brain areas are known to play a role in this process based on online sensory feedback. This can be measured by EEG. However, there is only limited knowledge about brain activity during predictive preparation for drop landings (DL). The purpose is to demonstrate changes in brain activity in preparation for DL in different conditions. After resting, 10 athletes performed a series of DLs and were asked to concentrate on the landing preparation for 10s before an auditory signal required them to drop land from a 30cm platform. This task was executed before and after a standardized fatigue protocol. EEG spectral power was calculated during DL preparation. Frontal Theta power was increased during preparation compared to rest. Parietal Alpha-2 power demonstrated higher values in preparation after fatigue condition while lower limb kinematics remained unchanged. Cortical activity in frontal and parietal brain areas is sensitive for predictive sensorimotor control of drop landings. Frontal Theta power demonstrates an increase and is related to higher attentional control. In a fatigued condition the parietal Alpha-2 power increase might be related to a deactivation in the somatosensory brain areas.
|
|
| 7. |
|
|
| 8. |
- Bjarnegård, Niclas, et al.
(författare)
-
Vascular Adaptation to Indoor Cycling Exercise in Premenopausal Women
- 2019
-
Ingår i: International Journal of Sports Medicine. - : GEORG THIEME VERLAG KG. - 0172-4622 .- 1439-3964. ; 40:4, s. 245-252
-
Tidskriftsartikel (refereegranskat)abstract
- The early vascular adaptation to indoor cycling, a popular activity at many fitness centres, is incompletely evaluated. Forty two healthy women (21-45 years) underwent measurements of arterial wall properties and geometry as well as a maximal bicycle exercise test before and after a 3 months period during which 21 of the women joined indoor cycling classes at a gym 2-3 times per week, while 21 women served as time controls. Peak work load increased by in average 16% (pamp;lt;0.001) and ascending aortic diameter by 4% (pamp;lt;0.01) in the exercise group, while unchanged in control group. The exercise intervention had no significant influence on the local intima-media thickness, blood pressure or the pulse pressure wave configuration while the carotid artery distensibility (pamp;lt;0.05) was higher after the intervention. There was a positive correlation between change in () peak work load and -diameter of tubular ascending aorta (r=0.42, pamp;lt;0.01) in the exercise group. In conclusion, after only 3 months of bicycle exercise training, signs of central arterial remodelling were seen in premenopausal women, which was associated to improvement in exercise capacity.
|
|
| 9. |
- Bjerkefors, Anna, et al.
(författare)
-
Effects of kayak ergometer training on motor performance in paraplegics.
- 2006
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 27:10, s. 824-9
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to assess the effects of kayak ergometer training on functional tests performed in wheelchair by persons with spinal cord injury. Ten post-rehabilitated persons with thoracic spinal cord injury volunteered for the study and performed 30 sessions of kayak ergometer training during a 10-week period. The ergometer was modified with an additional balance demand in the medio-lateral direction. Before and after the training period the subjects performed functional tests in the wheelchair: Sit-and-reach tests (distance), mounting a platform, transfer to a bench (height), propelling the wheelchair: 5 m on the rear wheels; in a figure-8; 15 m on a level surface and 50 m on a 3 degrees inclined surface (time). Test-retests were performed for all tests before the training began. A written questionnaire was distributed to evaluate the subjective experiences of the training. The test-retest resulted in coefficient of variation of 1.3 - 4.6 %. There were significant improvements in sit-and-reach (14 %), mounting a platform (7 %), transfer to a bench (10 %), propelling on level (3 %), and inclined surface (6 %). Furthermore, the training, did not cause any shoulder pain or other problems. This, and the positive subjective experience expressed by the subjects after the training indicate that this type of training is a suitable activity for persons with thoracic spinal cord injury.
|
|
| 10. |
- Bjerkefors, Anna, 1966-, et al.
(författare)
-
Seated Double-Poling Ergometer Performance of Individuals with Spinal Cord Injury - A New Ergometer Concept for Standardized Upper Body Exercise
- 2013
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 34:2, s. 176-182
-
Tidskriftsartikel (refereegranskat)abstract
- This study aimed to evaluate biomechanics during seated double-poling exercises in individuals with spinal cord injury (SCI) and to compare these with those of able-bodied persons (AB). 26 participants volunteered for the study; 13 with SCI (injury levels C7-T12), and 13 AB. A seated double-poling ergometer (SDPE) was developed. 3-dimensional kinematics was measured and piezoelectric force sensors were used to register force in both poles for calculation of power during incremental intensities. Significantly lower power outputs, (143.2 ± 51.1 vs. 198.3 ± 74.9 W) and pole forces (137.1 ± 43.1 vs. 238.2 ± 81.2 N) were observed during maximal effort in SCI compared to AB. Sagittal upper trunk range of motion increased with intensity and ranged from 6.1–34.8 ° for SCI, and 6.9–31.3 ° for AB, with larger peak amplitudes in flexion for AB (31.4 ± 12.9 °) compared to SCI (10.0 ± 8.0 °). All subjects with SCI were able to exercise on the SDPE. Upper body kinematics, power and force outputs increased with intensity in both groups, but were in general, lower in SCI. In conclusion, the SDPE could be successfully used at low to high work intensities enabling both endurance and strength training for individuals with SCI
|
|
| 11. |
- Bolam, Kate A., et al.
(författare)
-
A Comparison of Bone Mineral Density in Amateur Male Boxers and Active Non-boxers.
- 2016
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 37:9, s. 694-699
-
Tidskriftsartikel (refereegranskat)abstract
- To examine the site-specific osteogenic effect of upper limb impact-loading activity we compared the forearm and arm bone mineral density (BMD) of male boxers to that of active controls. A cross-sectional study was performed with 30 amateur male boxers (aged 18-44 years) and 32 age-matched, non-boxing, active controls. Participants had their regional and whole body BMD and bone mineral content (BMC) assessed by dual-energy X-ray absorptiometry. Hand grip strength, testosterone, oestradiol, sex hormone-binding globulin, vitamin D, lean and fat mass, and past and current physical activity were also assessed. Forearm and arm BMD were 1.5-2.2% higher in boxers than the control group although this was not statistically significant (p>0.05), with no significant difference for BMC (p>0.05). There were no differences between groups for spine, hip, or whole body BMD or BMC, or for body composition or hormone status. Within the arms, lean mass was associated with BMD and BMC in both boxers and the control group (BMD, r=0.60-0.76, p<0.001; BMC, r=0.67-0.82, p<0.001). There were no significant differences between amateur boxers and the control group for upper limb BMD and BMC. However, muscle mass appears to be particularly important to bone health of the upper limbs.
|
|
| 12. |
- Brynhildsen, Jan, 1962-, et al.
(författare)
-
Previous Injuries and Persisting Symptoms in Female Soccer Players
- 1990
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 11:6, s. 489-492
-
Tidskriftsartikel (refereegranskat)abstract
- One hundred and fifty players in a female senior soccer division, starting up a new season, were examined for past injuries and persisting symptoms. An incidence of 0.18 injury/player/year was found, which is not significantly different from previously reported injury rates for male soccer. Sprains to the lower extremity and shinsplints were the most common previous injuries. Forty-three percent of the players had some kind of persistent symptom as a result of a past injury. Symptoms from previous ankle and knee sprains and from overuse injuries were the most common. Players who had sustained an ankle joint injury were more prone to have persistent symptoms (p < 0.05) if they had persistent mechanical instability. Compared to previous retrospective studies on men's soccer, the women showed a higher rate of previous patellar dislocations. These injuries often caused persistent symptoms. The women showed fewer serious knee injuries. This might depend on a real difference in incidence or is just a reflection of female players ceasing to play soccer after a severe knee injury.
|
|
| 13. |
|
|
| 14. |
|
|
| 15. |
- Campion, F., et al.
(författare)
-
Bone Status in Professional Cyclists
- 2010
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 31:7, s. 511-515
-
Tidskriftsartikel (refereegranskat)abstract
- Professional cycling combines extensive endurance training with non weight-bearing exercise, two factors often associated with lower bone mineral density (BMD). Therefore BMD was measured with dual-energy x-ray absorptiometry in 30 professional road cyclists (mean (SD) age: 29.1 (3.4) years; height: 178.5 (6.7) cm; weight: 71.3 (6.1) kg; %fat mass: 9.7 (3.2)%; (V) over dotO(2) max: 70.5 (5.5) ml . kg(-1) . min(-1)) and in 30 young healthy males used as reference (28.6 (4.5) years; 176.5 (6.3) cm; 73.4 (7.3) kg; 20.7 (5.8)%). Adjusting for differences in age, height, fat mass, lean body mass, and calcium intake by ANCOVA, professional cyclists had similar head BMD (p = 0.383) but lower total body (1.135 (0.071) vs. 1.248 (0.104) g . cm(-2); p < 0.001), arms (0.903 (0.075) vs. 0.950 (0.085), p = 0.028), legs (1.290 (0.112) vs. 1.479 (0.138); p < 0.001), spine (0.948 (0.100) vs. 1.117 (0.147) g . cm(-2); p < 0.001), pelvis (1.054 (0.084) vs. 1.244 (0.142), p < 0.001), lumbar spine (1.046 (0.103) vs. 1.244 (0.167), P < 0.001), and femoral neck BMD (0.900 (0.115) vs. 1.093 (0.137), p < 0.001) compared to reference subjects. Professional cycling appears to negatively affect BMD in young healthy and highly active males, the femoral neck being the most affected site (-18%) in spite of the elevated muscle contractions inherent to the activity.
|
|
| 16. |
|
|
| 17. |
- Carlström, Eric, 1957, et al.
(författare)
-
Medical Emergencies During a Half Marathon Race - The Influence of Weather
- 2019
-
Ingår i: International Journal of Sports Medicine. - Stuttgart : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 40:5, s. 312-316
-
Tidskriftsartikel (refereegranskat)abstract
- The aim was to analyze the influence of weather conditions on medical emergencies in a half-marathon, specifically by evaluating its relation to the number of non-finishers, ambulance-required assistances, and collapses in need of ambulance as well as looking at the location of such emergencies on the race course. Seven years of data from the world's largest half marathon were used. Meteorological data were obtained from a nearby weather station, and the Physiological Equivalent Temperature (PET) index was used as a measure of general weather conditions. Of the 315,919 race starters, 104 runners out of the 140 ambulance-required assistances needed ambulance services due to collapses. Maximum air temperature and PET significantly co-variated with ambulance-required assistances, collapses, and non-finishers (R (2) =0.65-0.92; p=0.001-0.03). When air temperatures vary between 15-29 degrees C, an increase of 1 degrees C results in an increase of 2.5 (0.008/1000) ambulance-required assistances, 2.5 (0.008/1000) collapses (needing ambulance services), and 107 (0.34/1000) non-finishers. The results also indicate that when the daily maximum PET varies between 18-35 degrees C, an increase of 1 degrees C PET results in an increase of 1.8 collapses (0.006/1000) needing ambulance services and 66 non-finishers (0.21/1000).
|
|
| 18. |
|
|
| 19. |
|
|
| 20. |
|
|
| 21. |
|
|
| 22. |
|
|
| 23. |
- Díaz, Miguel M., Högskoleadjunkt, et al.
(författare)
-
Salivary nitric oxide and alpha-amylase as indexes of training intensity and load
- 2013
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 34:1, s. 8-13
-
Tidskriftsartikel (refereegranskat)abstract
- This study examined the variation in salivary nitric oxide (NO), alpha-amylase (sAA) and serum markers of muscle injury during 21 weeks of training in elite swimmers. Samples of saliva and blood were collected once a month during 5 months from 11 male professional athletes during their regular training season. The variation in each marker throughout the 21 weeks was compared with the dynamics of trainingvolume, intensity and load. Unstimulated whole saliva was assessed for NO and sAA whereas venous blood was assessed for lactate dehydrogenase, creatine kinase, and γ-glutamyltransferase. Nitric oxide and sAA showed a proportional response to the intensity of training. However, whereas the concentration of NO increased across the 21 weeks, the activity of sAA decreased. Similar variations in the concentration of NO and the markers of muscle injury were also observed. The higher concentration of NO might be attributed to changes in haemodynamics and muscle regenerative processes. On the other hand, autonomic regulation towards parasympathetic predominance might have been responsible for the decrease in sAA activity. These findings provide appealing evidence for the utilization of salivary constituents in sports medicine to monitor training programmes.
|
|
| 24. |
- Díaz, Miguel, Högskoleadjunkt, et al.
(författare)
-
Response of salivary markers of autonomic activity to elite competition
- 2012
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 33:9, s. 763-768
-
Tidskriftsartikel (refereegranskat)abstract
- We investigated the response of salivary total protein (TP), alpha-amylase (sAA) and chromogranin A (CgA) to sporting competition and their relation with positive and negative affect. 11 professional swimmers were examined during the first day of a national contest and on a recreated event that matched time-of-the-day and day-of-the-week assessments 2 weeks later. Total protein was determined by the Bradford method and sAA and CgA by Western blotting upon awakening, 30 and 60 min post awakening, immediately before warming up for competition and 5, 20 and 60 min after competition. Psychometric instruments included the Positive Affect and Negative Affect Schedule-X. The concentrations of TP, sAA and CgA differed from controls only prior to and 5 min after the event. We observed positive correlations between higher negative affect scores with higher levels of TP, sAA and CgA prior to the event on the competition day. All 3 markers showed a similar reactivity to sporting competition, which may be attributed to the mechanisms responsible for protein secretion into saliva when collection is performed with no exogenous stimulation. TP is an attractive marker in sports psychology since its determination is faster and cheaper than traditional kinetic or immune assays.
|
|
| 25. |
- Ekelund, Ulf, 1960-, et al.
(författare)
-
Field evaluation of the Computer Science and Application's Inc. Activity monitor during running and skating training in adolescent athletes
- 2000
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 21:8, s. 586-592
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigated the validity of the CSA activity monitor for assessment of the total amount of physical activity in adolescent athletes. Activity data were compared to data on daily energy expenditure and its derivatives measured by the doubly labeled water method. Seven athletes (speed skaters) with a mean age of 18.2+/-1.1 y were monitored twice (off-season and pre-season) by the activity monitor for eight consecutive days. The primary training during the off-season period was running whereas the pre-season period mainly involved skate training (i.e. inline skating, slideboard training, and skating imitations). Activity counts were significantly correlated to all energy estimates during the off-season period (r=0.93-0.96; P<0.01) whereas not during the pre-season period (r=0.32-0.57). A two-way multivariate analysis of variance showed a significant period effect for activity counts (668+/-163 vs. 548+/-91; P=0.026) whereas not for total daily energy expenditure (15.7+/-2.1 MJ x d(-1) vs. 16.0+/-1.0 MJ x d(-1); P=0.71). The relationship between activity counts and total daily energy expenditure seems to be affected by different training conditions. Therefore these circumstances have to be carefully considered in the interpretation of activity monitor data.
|
|
| 26. |
|
|
| 27. |
- Ericson, Mats O, et al.
(författare)
-
Efficiency of pedal forces during ergometer cycling.
- 1988
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 9:2, s. 118-22
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to record the forces applied to the pedal during ergometer cycling and to calculate the effectiveness of these force vectors. Six healthy subjects rode a weight-braked bicycle ergometer at different work loads, pedaling rates, saddle heights, and pedal foot positions. The left lower limb and crank motions were recorded by a cinefilm camera and pedal reaction forces by a Kistler force measuring transducer mounted on the left pedal. The force effectiveness was computed as a ratio between the force tangential to instantaneous direction of pedal movement and the resultant force. The mean force efficiency ratio significantly increased by an increase of the ergometer work load or use of the anterior foot position instead of the posterior. It was not significantly changed due to alterations of the pedaling rate or saddle height.
|
|
| 28. |
|
|
| 29. |
|
|
| 30. |
- Essen-Gustavsson, Birgitta
(författare)
-
Greater Performance Impairment of Black Runners than White Runners when Running in Hypoxia
- 2014
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 35, s. 809-816
-
Tidskriftsartikel (refereegranskat)abstract
- This study aimed to compare the response of performance-matched black and white runners during maximal and sub-maximal running in normoxic and hypoxic conditions. 14 well-trained runners (8 black, 6 white) performed 2 incremental maximal exercise tests and 2 fatigue resistance tests at 21 % O-2 (normoxia) or 14 % O-2 (hypoxia). Respiratory parameters, heart rate (HR), lactate concentration ([La-]) as well as arterial saturation (SpO(2)) were measured. Enzyme activities and myosin heavy chain content (MHC) were also measured. White runners reached a significantly greater peak treadmill speed and a higher HRmax than black runners in hypoxia (p < 0.05). Additionally, White runners achieved a greater time to fatigue than black runners (p < 0.05), with black runners displaying a greater decline in performance in hypoxia compared to normoxia (20.3 % vs. 13.4 %, black vs. white, respectively). However, black runners presented lower [La-] and higher SpO(2) than white runners in hypoxia (p < 0.05). Black runners had a higher proportion of MHC IIa and higher lactate dehydrogenase activity (p < 0.05). The greater performance impairment observed in black runners in hypoxia suggests a greater performance sensitivity to this condition, despite the maintenance of physiological variables such as SpO(2) and [La-] within a smaller range than white runners.
|
|
| 31. |
|
|
| 32. |
|
|
| 33. |
|
|
| 34. |
|
|
| 35. |
- Fridén, Jan, et al.
(författare)
-
Adaptive Response in Human Skeletal Muscle Subjected to Prolonged Eccentric Training
- 1983
-
Ingår i: International Journal of Sports Medicine. - 0172-4622 .- 1439-3964. ; :4, s. 177-183
-
Tidskriftsartikel (refereegranskat)abstract
- The peripheral adaptation process associated with repeating eccentric training over a longer period of time was studied in m. vastus lateralis of eleven healthy males aged 24 +/- 4 years. The maximal dynamic concentric muscle strength was only slightly improved after 8 weeks of training. However, eccentric work capacity was dramatically increased (375%). A maximal eccentric stint immediately after fulfilled 8 weeks of training caused a selective glycogen depletion from the type 28 fibers. An increased number of type 2C fibers was observed. The ultrastructure analysis showed an essentially well-preserved fine structure. Volume density of mitochondria was somewhat higher in all fiber types after training. Z-band widths were not affected by eccentric training. It is concluded that skeletal musculature adapts itself in a functional manner to the extreme tension demands put on them. Improved coordination and reorganization of the contractile apparatus of muscle fibers are the determining mechanisms of this adaptation.
|
|
| 36. |
- Gauffin, Håkan, et al.
(författare)
-
Function testing in patients with old rupture of the anterior cruciate ligament
- 1990
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 11:1, s. 73-77
-
Tidskriftsartikel (refereegranskat)abstract
- Fifteen patients with isolated old rupture of the anterior cruciate ligament (ACL) were examined to judge their functional disability. The following basic factors were used for evaluation: thigh muscle strength testing, stabilometry in a one-leg stance with straight and flexed knee, gait analysis, performance tests, knee function score, activity grading scale, and clinical joint laxity tests. We found that these rehabilitated patients mainly had impaired performance in those tests which greatly stressed the knee joint's sagittal stability. One-leg hop length was impaired for the injured limb. This group of patients had bilateral impairment of postural control compared with a reference group. This dysfunction was not revealed when comparing limbs. A derotation brace (ECKO) had neither a positive nor a negative effect in the tests. Different aspects of knee function evaluation are emphasized. Some of the altered functions are suggested to be due to central adjustments of motor control.
|
|
| 37. |
|
|
| 38. |
- Hannukainen, J, et al.
(författare)
-
In Vivo Measurements of Glucose Uptake in Human Achilles Tendon During Different Exercise Intensities
- 2005
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 26, s. 727-731
-
Tidskriftsartikel (refereegranskat)abstract
- Muscular contraction and loading of adjacent tendons has been demonstrated to cause increased blood flow and metabolic activity in the peritendinous region. However, it is poorly known to what extent the human tendon itself takes up glucose during exercise. Thus, the purpose of this study was to measure tendon glucose uptake with increasing exercise intensity and to compare it to muscle glucose uptake at the same intensities. Eight young men were examined on three separate days during which they performed 35 min of cycling at 30, 55 and 75 % of VO2max, respectively. Glucose uptake was measured directly by positron emission tomography (PET) with 2-[ (18)F]fluoro-2-deoxyglucose ([18F]FDG). [18F]FDG was injected after 10 min of exercise that was continued for a further 25 min after the injection. PET scanning of the thigh and Achilles region was performed after the exercise. Glucose uptake of the Achilles tendon (AT) remained unchanged (7.1 +/- 1.5, 6.6 +/- 1.1, and 6.0 +/- 1.1 micromol.kg(-1).min(-1)) with the increasing workload, although the glucose uptake in m. quadriceps femoris simultaneously clearly increased (48 +/- 35, 120 +/- 35, and 152 +/- 74 micromol.kg(-1).min(-1), p < 0.05). In conclusion, the AT takes up glucose during exercise but in significantly smaller amounts than the skeletal muscle does. Furthermore, glucose uptake in the AT is not increased with the increasing exercise intensity. This may be partly explained by the cycle ergometry exercise used in the present study, which probably causes only a little increase in strain to the AT with increasing exercise intensity.
|
|
| 39. |
- Hedman, Kristofer, 1984-, et al.
(författare)
-
Left Ventricular Adaptation to 12 Weeks of Indoor Cycling at the Gym in Untrained Females.
- 2017
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 38:9, s. 653-658
-
Tidskriftsartikel (refereegranskat)abstract
- Cross-sectional studies provide evidence of larger cardiac dimensions and mass in endurance trained than in untrained females. Much less is known regarding adaptations in cardiac function following training in untrained subjects. We aimed to study left ventricular (LV) adaptation to indoor cycling in previously untrained females, in regard of LV dimensions, mass and function. 42 sedentary females were divided into 2 equally sized groups, either training indoor cycling at regular classes at a local gym for 12 weeks, in average 2.6 times per week, or maintaining their sedentary lifestyle. Echocardiography at rest and a maximal exercise test were performed before and after the intervention. Exercise capacity increased in average 16% in the exercise group (p<0.001), together with decreased heart rate at rest (p<0.05) and at 120 watts steady-state (p<0.001). There were no difference in systolic or diastolic function following the intervention and minimal increases in LV internal diameter in diastole (+1 mm, p<0.01). LV mass was unchanged with training (137±25 vs. 137±28 g, p=0.911). Our findings indicate that attending indoor cycling classes at a gym 2-to-3 times per week for 12 weeks is enough to improve exercise capacity, while a higher volume of training is required to elicit cardiac adaptations.
|
|
| 40. |
|
|
| 41. |
|
|
| 42. |
|
|
| 43. |
|
|
| 44. |
|
|
| 45. |
- Kalliokoski, K K, et al.
(författare)
-
Perfusion distribution between and within muscles during intermittent static exercise in endurance-trained and untrained men
- 2003
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 24, s. 400-403
-
Tidskriftsartikel (refereegranskat)abstract
- We have recently shown that muscle perfusion varies between different quadriceps femoris muscles during submaximal exercise in humans. In animals, endurance training changes perfusion distribution between muscles during exercise. Whether the same is observed in humans is currently unknown. Therefore, we compared perfusion levels between different parts of the quadriceps femoris muscle group during one-legged intermittent static exercise in seven endurance-trained and seven untrained men. Muscle perfusion was measured using positron emission tomography with [ 15O]-H 2 O. In addition, relative dispersion of perfusion (standard deviation within a region/mean within a region x 100 %) within each muscle region was calculated as an index of perfusion heterogeneity within the muscles. Muscle perfusion tended to be lower in endurance-trained men (p = 0.16) and it was also different between the regions (p < 0.001). However, perfusion distributed similarly between the groups (p = 0.51). Relative dispersion of perfusion within the muscles was lower in endurance-trained men (p = 0.01) and it was also different between muscles (p < 0.001). These results suggest that endurance training does not alter perfusion distribution between muscles, but it decreases perfusion heterogeneity within the muscles.
|
|
| 46. |
|
|
| 47. |
|
|
| 48. |
- Kenttä, Göran, et al.
(författare)
-
Training practices and overtraining syndrome in Swedish age-group athletes.
- 2001
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 22:6, s. 460-5
-
Tidskriftsartikel (refereegranskat)abstract
- Heavy training in combination with inadequate recovery actions can result in the overtraining/staleness syndrome and burnout. Even young and aspiring elite athletes develop staleness. The aim was therefore to determine the incidence and nature of staleness, and its association with training behavior and psychosocial stressors in young elite athletes. A sample of 272 individuals from 16 sports completed questionnaires on training, staleness, and psychosocial stress and 37% reported being stale at least once. The incidence rate was higher for individual sports (48%) compared with team (30%) and less physically demanding sports (18%). Stale athletes reported greater perceptual changes and negatively elevated mood scores in comparison to healthy athletes. Staleness was distinguished from burnout on the basis of motivational consequences; 41 % of the athletes lost their motivation for training, which in turn indicates a state of burnout. Further, 35 % of the athletes reported low satisfaction with time spent on important relationships, 29% rated the relationship with their coach as ranging from very, very bad to only moderately good. The results indicate that staleness is a widespread problem among young athletes in a variety of sports, and is not solely related to physical training, but also to non-training stressors.
|
|
| 49. |
- Larsson, Peter, et al.
(författare)
-
Body composition and performance in cross-country skiing.
- 2008
-
Ingår i: International Journal of Sports Medicine. - : Georg Thieme Verlag KG. - 0172-4622 .- 1439-3964. ; 29:12, s. 971-5
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to investigate the relationships between body composition and performance in cross-country skiing. Ten male college-aged elite cross-country skiers (17.9 yrs; S 1.0 yrs) participated in a 5.6-km cross-country skiing time trial and in dual energy X-ray absorptiometry (DXA, Lunar DPX-L, Madison, WI, USA) body composition measurements. A differential global positioning system (dGPS, GPS 12 CX, Garmin Int. Inc., Olathe, KS, USA; RXMAR 2, Aztec SA, Strasbourg, France) was used to compute speed in different sections of the course. Spearman correlation analyses were applied. Total body weight and absolute lean body mass were significantly related to final time (r = - 0.721; p < 0.05 and - 0.830; p < 0.01, respectively). Absolute lean arm mass (kg) was negatively correlated to final time (r = - 0.648; p < 0.05) and the relative lean arm mass was significantly related to speed mainly in uphill sections (r = 0.636 to 0.867; p < 0.05 to p < 0.01). We suggest that large amounts of lean body mass, especially in the arms, seem to be of great importance for cross-country skiing performance.
|
|
| 50. |
|
|
