| 1. |
- Alfredson, Håkan, et al.
(författare)
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Bone mass in female volleyball players : a comparison of total and regional bone mass in female volleyball players and nonactive females
- 1997
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Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 60:4, s. 338-342
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this cross-sectional study was to evaluate bone mass in female athletes participating in an impact loading sport (volleyball), and especially to investigate whether any changes in bone mass might be related to the type and magnitude of weightbearing loading and muscle strength. The volleyball group consisted of 13 first division players (age 20.9 +/- 3.7 years) training for about 8 hours/week, and the reference group consisted of 13 nonactive females (age 25.0 +/- 2.4 years) not participating in any kind of regular or organized sport activity. The groups were matched according to weight and height. Areal bone mineral density (BMD) was measured in total body, head, lumbar spine, femoral neck, Ward's triangle, trochanter, the whole femur, and humerus using dual-energy-X-ray absorptiometry. Isokinetic concentric peak torque of the quadricep and hamstring muscles was measured using an isokinetic dynamometer. Compared with the controls, the volleyball players had a significantly (P < 0.05-0.01) higher BMD of the total body (6.1%), lumbar spine (13.2%), femoral neck (15.8%), Ward's triangle (17.9%), trochanter (18.8%), nondominant femur (8.2%), and humerus (dominant 9.5%, nondominant 10.0%), but not of the head and the dominant whole femur. The dominant humerus showed significantly higher BMD than the nondominant humerus in both the volleyball and nonactive group (P < 0.05). There was no significant difference in muscle strength of the thigh between the two groups. In the nonactive group, muscle strength in the quadriceps, and especially hamstrings, was correlated to BMD of the adjacent bones (whole femur, hip sites) and also to distant sites (humerus). However, in the volleyball group there were no correlations between muscle strength and BMD of the adjacent bones, but quadricep strength correlated to BMD of the humerus. These results clearly show that young female volleyball players have a high bone mass. The demonstrated high bone mass seems to be related to the type of loading subjected to each BMD site. Muscle strength of the thigh seems to have little impact on BMD in female volleyball players.
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| 2. |
- Alfredson, Håkan, et al.
(författare)
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Bone mass in the calcaneus after heavy loaded eccentric calf-muscle training in recreational athletes with chronic achilles tendinosis
- 1999
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Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 64:5, s. 450-455
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Tidskriftsartikel (refereegranskat)abstract
- In an ongoing prospective study of 14 recreational athletes (12 males and 2 females, mean age 44.2 +/- 7.1 years) with unilateral chronic Achilles tendinosis, we investigated the effect of treatment with heavy-loaded eccentric calf-muscle training. Pain during activity (recorded on a VAS scale) and isokinetic concentric and eccentric calf-muscle strength (peak torque at 90 degrees /second and 225 degrees /second) on the injured and noninjured side were evaluated. In this group of patients, we examined areal bone mineral density (BMD) of the calcaneus after 9 months (range 6-14 months) of training. BMD of the injured side (subjected to heavy-loaded eccentric training) was compared with BMD of the noninjured side. Before onset of heavy-loaded eccentric training, all patients had Achilles tendon pain which prohibited running activity, and significantly lower concentric and eccentric plantar flexion peak torque on the injured compared with the noninjured side. The training program consisted of 12 weeks of daily, heavy-loaded, eccentric calf-muscle training; thereafter the training was continued for 2-3 days/week. The clinical results were excellent-all 14 patients were back at their preinjury level with full running activity at the 3 month follow-up. The concentric and eccentric plantar flexion peak torque had increased significantly and did not significantly differ from the noninjured side at the 3 and 9 month follow-up. There were no significant side-to-side differences in BMD of the calcaneus. There was no significant relationship between BMD of the calcaneus and calf-muscle strength. As a comparison group, we used 10 recreational athletes (5 males and 5 females) mean age 40.9 years (range 26-55 years), who were selected for surgical treatment of chronic Achilles tendinosis localized at the 2-6 cm level. Their duration of symptoms and severity of disease were the same as in the experimental group. There were no significant side-to-side differences in BMD of the calcaneus preoperatively, but 12 months postoperatively BMD of the calcaneus was 16.4% lower at the injured side compared with the noninjured side. Heavy-loaded eccentric calf-muscle training resulted in a fast recovery in all patients, equaled the side-to-side differences in muscle strength, and was not associated with side-to-side differences in BMD of the calcaneus. In this group of middle-aged recreational athletes, BMD of the calcaneus was not related to calf-muscle strength.
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| 3. |
- Alfredson, Håkan, et al.
(författare)
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High thigh muscle strength but not bone mass in young horseback-riding females
- 1998
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Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 62:6, s. 497-501
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Tidskriftsartikel (refereegranskat)abstract
- To evaluate whether the type of weight-bearing loading subjected to the skeleton during horseback-riding was associated with differences in bone mass and muscle strength of the thigh, we investigated bone mass and isokinetic muscle strength in 20 female horse riders (age 17.9 +/- 0.6 years) who were riding 7.0 +/- 3.4 hours/week, and 20 nonactive females (age 17.8 +/- 1.1 years). The groups were matched according to age, weight, and height. Areal bone mineral density was measured in total body, head, lumbar spine, right femoral neck, Ward's triangle, and trochanter, the whole dominant and nondominant humerus, and in specific sites in the right femur diaphysis, distal femur, proximal tibia, and tibia diaphysis using dual X-ray absorptiometry. Isokinetic concentric and eccentric peak torque of the quadricep and hamstring muscles were measured using an isokinetic dynamometer. There were no significant differences in bone mass between the horseback riders and nonactives at any site measured. The horse riders were significantly (P < 0.05-0.01) stronger in concentric hamstrings strength at 90 degrees/second and 225 degrees/second and in eccentric quadricep and hamstring strength at 90 degrees/second. Horseback riding in young females is associated with a high muscle strength of the thigh, but not with a high bone mass.
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| 4. |
- Alfredson, Håkan, et al.
(författare)
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Long-term loading and regional bone mass of the arm in female volleyball players
- 1998
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Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 62:4, s. 303-308
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Tidskriftsartikel (refereegranskat)abstract
- In the present study, we compared the bone mineral content (BMC) and bone mineral density (BMD) in the arms of 11 female volleyball players (mean age 22.0 +/- 2.6 years) training for about 8 hours/week, and 11 nonactive females aged 24.6 +/- 3.1 years (mean +/- SD) not participating in regular or organized sport activity. Using dual X-ray absorptiometry (DXA), BMC was measured in the proximal and distal humerus, and BMD in the distal radius. Isokinetic concentric peak torque (highest value attained during 5 or 10 repetitions) of the rotator muscles of the shoulder and flexor and extensor muscles of the elbow were measured using an isokinetic dynamometer. The volleyball players had significantly higher BMC (P < 0.05) at the proximal humerus of the dominant arm compared with the nonactive group, but there were no differences between the groups in BMC of the distal humerus and BMD of the distal radius. In the volleyball players, BMC was significantly higher at the proximal humerus, at the distal humerus, and at the distal radius in the dominant compared with the nondominant arm. In the nonactive group, there were no significant differences in BMC and BMD between the dominant and nondominant arm at any site measured. Except for shoulder internal rotation strength and elbow flexion strength at 90 degrees/second that was higher in the dominant arm in the volleyball players, there were no significant differences in muscle strength of the rotator muscles of the shoulder and flexor and extensor muscles of the elbow between the dominant and nondominant arm in the volleyball players and nonactive controls. In the volleyball players, but not in the nonactive controls, there were several significant relationships between shoulder and elbow strength and BMC at the distal humerus of the dominant and especially the nondominant arm. These results show that young female volleyball players have a higher bone mass in the proximal humerus, distal humerus, and distal radius in the dominant compared with the nondominant arm, and a higher bone mass in the proximal humerus compared with nonactive controls. Muscle strength of the rotator muscles of the shoulder is not related to the higher bone mass in the proximal humerus of the dominant arm. Theoretically, the observed differences in bone mass can be related to the type of loading the skeleton undergoes when playing volleyball.
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| 5. |
- Alfredson, Håkan, et al.
(författare)
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Prolonged progressive calcaneal bone loss despite early weightbearing rehabilitation in patients surgically treated for Achilles tendinosis
- 1998
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Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 62:2, s. 166-171
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Tidskriftsartikel (refereegranskat)abstract
- We prospectively evaluated areal bone mineral density (BMD) of the calcaneus and calf-muscle strength (concentric and eccentric plantar flexion peak torque in Nm) in 10 recreational athletes (5 males and 5 females), mean age 40.9 years (range 26-55), who were selected to undergo surgical treatment for chronic Achilles tendinosis localized at the 2-6 cm level. Surgery was followed by immobilization in a plaster cast for 2 weeks, followed by flexibility training and slowly progressing strength training and weight-bearing activity. One patient was excluded after week 0 because of a new injury. Seven patients were back to their preinjury activity at the 26-week control, and eight patients at the 52-week control postoperatively. BMD in the calcaneus and calf-muscle strength on the injured and noninjured side was measured preoperatively (week 0) and postoperatively (weeks 2, 6, 16, 26, and 52). There were no significant differences in BMD between the injured and noninjured side at weeks 0, 2, and 6, but at weeks 16, 26, and 52, BMD was significantly (P < 0.05) lower (11.5%, 18.4%, and 16.4%, respectively) in the calcaneus of the injured side. Concentric and eccentric plantar flexion strength were significantly lower on the injured side preoperatively. Eccentric, but not concentric plantar flexion strength had recovered compared with the noninjured side 1 year postoperatively. Calf-muscle strength was not related to bone mass in the calcaneus. As a comparison, we used a group of 11 recreational athletes (10 males and 1 female), with a mean age of 46.1 years (range 28.9-58.5) who had been surgically treated for chronic Achilles tendinosis at the 2-6 cm level 39.5 +/- 11.8 months ago. In this group, there was no significant difference in BMD of the calcaneus between the injured and noninjured side. It seems that there was a delayed and prolonged calcaneal bone loss despite early weightbearing loading in patients surgically treated for chronic Achilles tendinosis at the 2-6 cm level. Around that time, when the Achilles tendon had healed (4-6 months) and the athletes returned to their sports, the calcaneal bone had a relatively low BMD and might possibly be vulnerable to heavy loadings. There were no signs of recovery 1 year postoperatively, but in a comparison group there were no significant side-to-side differences 39.5 months postoperatively.
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| 6. |
- Alfredson, Håkan, et al.
(författare)
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Total and regional bone mass in female soccer players
- 1996
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Ingår i: Calcified Tissue International. - : Springer. - 0171-967X .- 1432-0827. ; 59:6, s. 438-442
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Tidskriftsartikel (refereegranskat)abstract
- This cross-sectional study investigated bone mass in female athletes participating in an impact-loading sport (soccer), and evaluated whether any changes in bone mass could be related to the type of weight-bearing loading and muscle strength. The group of soccer players consisted of 16 second-division female players (age 20.9 +/- 2.2 years) training for about 6 hours/week. The reference group consisted of 13 nonactive females (age 25.0 +/- 2.4 years) not participating in any kind of regular or organized sport activity. The groups were matched according to weight and height. Areal bone mineral density (BMD) was measured in total body, head, lumbar spine, femoral neck, Ward's triangle, trochanter, the whole femur and humerus, and in specific sites in femur diaphysis, distal femur, proximal tibia, and tibia diaphysis using dual X-ray absorptiometry. Isokinetic concentric peak torque of the quadriceps and hamstring muscles was measured using an isokinetic dynamometer. The soccer players had significantly (P < 0.05-0.01) higher BMD in the lumbar spine (10.7%), femoral neck (13.7%), Ward's triangle (19.6%), nondominant femur and humerus (8.2 and 8.0%, respectively), distal femur (12.6%), and proximal tibia (12.0%) compared with the nonactive women. There was no significant difference in muscle strength of the thigh between the two groups. In the nonactive group, muscle strength in the quadriceps and especially hamstrings, was correlated to BMD of the adjacent bones (whole femur, hip sites) and also to distant sites (humerus). In the soccer group, there were no correlations between muscle strength and BMD of the adjacent and distant bones. Soccer playing and training appears to have a beneficial effect on bone mass in young females, and it seems that there is a site-specific skeletal response to the type of loading subjected to each BMD site. Muscle strength in the thigh is not related to bone mass in female soccer players.
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| 7. |
- Bornefalk, Eva, et al.
(författare)
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Age-dependent effect of oral glucocorticoids on markers of bone resorption in patients with acute asthma
- 1998
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Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 63:1, s. 9-13
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Tidskriftsartikel (refereegranskat)abstract
- It is generally accepted that bone formation is depressed during corticosteroid treatment, but the effects of glucocorticoids on bone resorption are less well characterized. We have investigated the effects of short-term treatment with high-dose oral glucocorticoids on biochemical markers of bone turnover in 20 consecutive patients with asthma who sought help for acute respiratory obstruction in our emergency department. Serum concentrations of the carboxy-terminal cross-linked telopeptide of type 1 collagen (1CTP), reflecting bone resorption, and the carboxy-terminal propeptide of type 1 procollagen (P1CP), reflecting bone formation, were measured by radioimmunoassay. Changes of the circulating levels of the bone resorption marker 1CTP after treatment were age dependent with a significant negative correlation (r = -0.54, P = 0.01). The dependency on age remained when correcting, in a multiple linear regression analysis, for 1CTP levels at admission, weight, sex, and daily maintenance dose of inhaled glucocorticoids. Circulating levels of P1CP were suppressed in the whole group 1 week after initiation of glucocorticoid therapy, from 123.3 +/- 10.2 ng/ml at admission to 88.1 +/- 6.3 ng/ml after 1 week (P < 0.01). The changes in P1CP levels were not related to age. Our data indicate that bone formation is suppressed by glucocorticoids in all age groups, whereas the effect of glucocorticoids on markers of bone resorption is dependent on age.
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| 8. |
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| 9. |
- Brahm, Helena, et al.
(författare)
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Relationships between bone mass measurements and lifetime physical activity in a Swedish population
- 1998
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Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 0171-967X .- 1432-0827. ; 62:5, s. 400-412
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Tidskriftsartikel (refereegranskat)abstract
- Lifetime occupational and leisure time activities were assessed by a questionnaire in order to evaluate their relationship to bone mass measurements and biochemical markers of bone metabolism in a population of 61 women and 61 men, randomly selected from a Swedish population register, to represent ages between 22 and 85 years. We also considered possible confounders by using questions about smoking habits, milk consumption, hormone replacement therapy (HRT), and menopausal age. Bone mineral density (BMD) and bone mineral content (bone mass, BMC) of the total body, lumbar spine, and proximal femur (neck, trochanter, Ward's triangle) were measured by dual energy X-ray absorptiometry (DXA), and BMD of the forearm with single energy X-ray absorptiometry (SXA). In addition, both DXA and SXA provided information on bone area. Quantitative ultrasound measurements (QUS) at the heel were performed to assess the speed of sound (SOS) and broadband ultrasound attenuation (BUA). Fasting blood samples were analyzed for biochemical markers of bone metabolism as well as parathyroid hormone (PTH) and total serum calcium. After adjustment for confounding factors, neither BMD nor QUS measurements were consistently related to lifetime leisure time or occupational activities; nor were there any consistent patterns relating biochemical markers of bone metabolism to bone mass measurements. However, physical activity seemed to influence bone mass, area, and width more than density. In men, high levels of leisure time activity were associated with raised values for lumbar spine area (6.2%) and width (3.3%) as well as for femoral neck area (5.5%) compared with their low activity counterpart. Men exposed to high levels of occupational activity demonstrated lower lumbar spine BMD (10.9%) and area (5.3%) than men with low activity levels. Within an unselected Swedish population, estimation of lifetime occupational and sport activities as well as bedrest, using a questionnaire, demonstrated no major effects on bone density. However, the association between high levels of lifetime activity and raised values for bone mass, area, and width indicate that geometrical changes in bone may provide better estimations of mechanically induced bone strength than bone density, at least in men.
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| 10. |
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