- Email: [email protected]
Evaluation of the bone status in high level cyclists
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Abstracts / Bone 48 (2011) S266–S271
the quadriceps was used to induce paralysis of the right hind limb in Swiss-Webster mice; saline injection in the left side was used as control. Bone marrows from the left and right femurs were dissected after euthanasia at 0, 7, 14, 21 and 28 days post-BTX; RNAs were extracted to perform qPCR analyses. Bone loss was measured by microCT on the tibia upper extremity. On the right side, 3D measurements showed a significant decrease in bone volume as from 7 days (−31%) associated with microarchitectural changes that intensified in time (−45.9% at 21 days). Microarchitectural damages were observed from 7 days and were increased during the time course of the study. However, no significant difference in cortical thickness was observed. Expression of several bone formation factors was significantly altered as from 7 days post-BTX, such as alkaline phosphatase, TGFβ1, LRP5, sFRP2. Among them, only sFRP2 and LRP5 maintained a modified expression until 28 days post-ovariectomy. Modifications of expression of DKK1 was observed after 21 days and appeared as a late inhibitor of bone formation compared to sFRP2.Expression of bone resorption markers was increased as from 7 days and was maintained until 28 days (TRAcP, IL-6). RANKL was also increased but returned to a normal expression at 21 days. In conclusion, a localized disuse induces rapid modifications in the gene expression profile in the bone microenvironment leading to bone loss by an early decrease of bone formation factors associated with an increase in bone resorption. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.659
vitamin D status on overall health and in particular on muscle and bone function in Saudi Arabian females. The aims of this study were to: 1) determine the prevalence of hypovitaminosis D in Saudi pre and postmenopausal women; 2) investigate the effect of poor vitamin D status on physical performance. Methods: A total of 462 healthy women were recruited from the city of Jeddah through Primary Health Care Centres. Data are presented on 231 premenopausal [20–39 years]; and 231postmenopausal women [>51 years]. Menopausal grouping was confirmed by hormonal status. Fasting blood samples was collected for assessment of 25(OH)D status. Muscle function was assessed by the following tests: get up and go (GUG); 8 feet walk (8FW); five-times sit to stand (5STS). Results and discussion: Hypovitaminosis D was extensive amongst the women; with a total of 54.8% of women with 25OHD levels below <25 nmol/L (71% pre, 38.5% post), 85.1%< 50 nmol/L (93.5%pre, 76.6% post), and 95.7%< 75 nmol/L (97%pre, 94.4% post). For all women combined, a significant positive correlation was found between 25(OH)D and GUG (P< .001), 5-STS (P <.001), and 8FW (P<0.01). After adjusting for key confounding factors including BMI, the correlation remained significant for 5-STS (P <0.01). When women were classified into ‘severely deficient’ (<25 nmol/L) and ‘insufficient’ (>25 nmol/L) groups, the positive correlation between muscle function tests and 25OHD remained significant in the ‘deficiency’ group but disappeared in the ‘insufficiency’ group. When women with 25(OH)D status between 25–50 nmol/L and >50 nmol/L and >75 nmol/L were investigated, the correlations disappeared. Conclusion: These data suggest that low vitamin D status (<25 nmol/L) is not associated with poor physical performance and may be a reflection of muscle ‘adaptation’ to prolonged, life-cycle of hypovitaminosis D. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.661
PP529-S The effect of bone mineral density of distal radius exposed to vibration on rest activity of contralateral wrist flexor I. Karacan a, ⁎, M. Cidem b, C. Bahadir c, A. Rezvani a, A. Ozen d, H.I. Unalan e a Physical Medicine & Rehabilitation Dept, Bezmi Alem Vakif University, Istanbul, Turkey b Physical Medicine & Rehabilitation Dept, Danistay Healthy Center, Ankara, Turkey c Erenkoy Physical Medicine and Rehabilitation Hospital, Istanbul, Turkey d Nuclear Medicine, Bagcilar Training & Research Hospital, Istanbul, Turkey e Physical Medicine & Rehabilitation Dept, IU Cerrahpasa Medical Faculty, Istanbul, Turkey Abstract: The aim of this study was to investigate whether distal radius exposed to vibration had an effect associated with its bone mineral density (BMD) or content on the rest muscle activity of untrained-contralateral flexor carpi radialis (FCR). This study was conducted on 90 healthy adult volunteers. The rest electrical activities (EMGrms) of the right and left FCR muscle were simultaneously measured before, during and after vibration. The standardized rest-EMGrms (rest EMGrms of the left FCR / rest EMGrms of the right FCR ratio) were calculated for the left FCR muscle. The right distal radius BMD was measured by DXA. The rest-EMGrms of the untrained-left FCR muscle significantly increased during vibration. The increase in the rest-EMGrms was much more apparent in the trained-right FCR muscle than untrained-left FCR muscle during vibration. The right ultradistal radius BMD was an independent predictor for rest-EMGrms of the left FCR muscle measured during vibration. The standardized rest-EMGrms-during the vibration were significantly lower compared to standardized rest-EMGrms-preVibration and standardized restEMGrms-postVibration. The right ultradistal radius BMD was independent predictors for the standardized rest-EMGrms-during vibration. It may be suggested that radius bone exposed to cyclic mechanical loading can regulate muscle activity in the untrained-contralateral limb, based on its BMD. Keywords: Vibration, Contralateral muscle activity, Bone mineral density. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.660
PP531-T Usefulness of motor function tests in predicting new vertebral fractures K. Nawata a,b, ⁎, M. Yamauchi a, S. Takaoka a, T. Sugimoto a a Internal Medicine 1, Shimane University Faculty of Medicine, Izumo, Japan b Health and Nutrition, The University of Shimane, Matsue, Japan Abstract: Aim: Decreases in muscle strength and balance function are thought to lead to reduction of bone mineral density (BMD) and increases in the frequency of falls, and to contribute to osteoporotic fractures. Regarding the relationship between motor function tests and fracture, a longitudinal study reported that leg strength, walking speed, and leg motor coordination are useful predictive factors for hip fracture. However, no useful predictive factors have been identified for vertebral fractures. We therefore investigated the usefulness of motor function tests in predicting new vertebral fractures. Subjects and Methods: Subjects were 63 healthy postmenopausal women. BMD was measured using the DXA method at the lumbar vertebrae (L2–4) and femoral neck (FN), and the presence or absence of vertebral fractures was confirmed on X-ray. CTX, intact PTH, 25-hydoroxyvitamin D [25(OH)D] and undercarboxylated osteocalcin (ucOC) were measured. Motor function tests included standing up from chair test, tandem walk test and standing on one foot test as well as measurements of grip strength, maximum step length (MSL) and 10 mwalking speed. The presence or absence of new vertebral fractures was evaluated following a mean observation period of 2.6 years. Results: The subjects' mean values were as follows: age, 62 ± 7 years; height, 152.6 ± 5.3 cm; weight, 53.6 ± 7.9 kg; BMI, 23.0 ± 3.1 kg/m 2; L2–4 BMD, 0.87 ± 0.14 g/cm 2 (T-score, − 1.3); FN BMD, 0.64 ± 0.08 (− 1.3); CTX, 0.39 ± 0.15 ng/ mL; PTH, 43.4 ± 14.0 pg/mL; 25(OH)D, 17.2 ± 4.4 ng/mL; ucOC, 5.4 ± 3.4 ng/mL. Results on motor function tests were as follows: grip strength, 23.3 ± 3.1 kg; MSL, 107 ± 10 cm; and MSL adjusted for the length of lower limbs (% MSL), 137 ± 14%. Subjects had age-appropriate motor function. No differences based on presence or absence of new vertebral fractures were observed for BMD, CTX and 25(OH)D. On motor function tests, a significantly lower value was observed in the new vertebral fracture present group for only % MSL (present group 139 ± 14%, vs. absent group 128 ± 13%, p < 0.05). % MSL was also identified as a significant predictive factor for vertebral fracture [odds ratio, 0.92 (95%CI: 0.86–0.99), p < 0.05] following correction for age, BMI, L2–4 BMD, CTX, PTH, 25(OH)D, ucOC, presence of existing fragility fracture and observation period on logistic regression analysis. Conclusion: MSL was considered a useful factor for predicting the risk of new vertebral fractures independently of BMD, bone metabolism markers and 25(OH)D. This article is part of Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.662
PP530-M Effect of extensive hypovitaminosis D on muscle and physical performance in Saudi women K.S. Hussein a,b, ⁎, M.S.S. Ardawi c, S.L. New b, H.A. Al-kadi a a Physiology, King Abdulaziz University, Jeddah, Saudi Arabia b Nutritional Sciences, Surrey University, Guildford, UK c Clinical Biochemistry, King Abdulaziz University, Jeddah, Saudi Arabia
PP532-S Evaluation of the bone status in high level cyclists G. Guillaume a, D. Chappard b, M. Audran c, ⁎ a Institut du Sport, Paris, France b IRIS -IBS Institut de Biologie en Santé, INSERM, U922-LHEA, France c CHU ANGERS, Rheumatology Unit, Angers, France
Introduction and aims: Vitamin D deficiency, which is common among elderly people, is associated with reduced muscle strength. Few data exist, however, on the implications of poor
Abstract: The effects of physical exercise and sport on bone mass have been the subject of many studies, the results of which are largely determined by the type of exercise. It was thus
Abstracts / Bone 48 (2011) S266–S271 observed that the sports that generate weight bearing, with repeated impact loading have a more favorable effect than sports activities that do not, like swimming or cycling. Aim: We report the results of measurements of bone mineral density as well as biological parameters in professional cyclists of high level, subjected to regular training and tough competitions. Patients, methods: 29 professional runners were studied (aged 26.5± 5.3 yrs; BMI: 21.7± 1.6 kg/m 2; seniority in the occupation: 4.5 ±4 yrs; traversed annual distance 27933 ± 2626 km). Bone density measurements (BMD) were performed in 20 cyclists in the same center of densitometry using a Hologic Discovery C device at the lumbar, femoral (total and trans-cervical) and radial sites. Values were expressed as Z-score according to the reference data given by the manufacturer, Hologic (USA). Biological parameters related to bone metabolism were obtained in 29 cyclists: serum calcium, phosphate, creatinine, alkaline phosphatase (AP), serum osteocalcin (OC), 25(OH)vit.D, testosterone, IGF-1, TSH. Results: BMD data (Z-score) are given below. Five runners had a low lumbar BMD. Mean BMD Z-score was −1.21 ±.42 at the femoral neck −1.22± .21 at the total femur. The lowest values of BMD were measured at the mid radius site: mean Z score −1.77 ± .78 (Fig. 1). In 29 cyclists serum calcium and kidney function were in the normal range. Biochemical parameters of bone formation (OC, AP) were normal; individual values of 25(OH)vit.D ranged from 29 to 143 mmol/l (mean: 74 mmol/l). A significant inverse relationship was found between IGF-1 and lumbar BMD. Conclusion: We observed in highly trained professional master cyclists,
Image/Graph
Fig. 1.
low BMD at different sites. With the increased risk of severe falls, our data underline the need to pay greater attention to the bone status of these high level athletes. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared.
doi:10.1016/j.bone.2011.03.663
PP533-M The effect of walking exercise on bone mass density in young thin women with osteopenia N. Habibzadeh ⁎ Department of Sport Sciences, University of Guilan, Rasht, Islamic Republic of Iran
Abstract: Osteoporosis is a widespread disorder for women, that causes bone fractures after simple trauma in them. But exercise is long being known to reduce the risk of osteoporosis. Therefore this study aims to investigate the effect of walking program on bone mass density in order to reduce bone loss and osteoporosis in thin young women. Twenty thin (BM I < 20) osteopenic women with age 22.00 ± 1.50 years volunteered to participate in this study. Then they were randomly assigned to exercise (n = 10) and control (n = 10) groups. Before and after the training program both groups had anthropometric measurements, blood analysis. Bone mass density was evaluated by using dual-energy X-ray absorptiometry (DXA) at hip and spin (L2–L4). Each walking session was 30 min walking at 50–75% of maximal heart rate, 3 days per week, for 2 months. After 2 months, exercise group had no effect assignment on BMD at the spin (L2–L4) and hip (p > 0.05). However they experienced slight increase in BMD at both regions, while the control group did not. Also no change was observed in bloods factors (p > 0.05). Percent body fat, fat mass and lean mass changes in response to training were significant in the exercise group (all p = 0.000).This study demonstrated that walking exercise may have reduced the risk of bone loss, even though it did not significantly increase bone density .However further studies are needed to evaluate the effect of walking exercise on BMD and the risk of osteoporosis in thin osteopenic women. This article is part of a Special Issue entitled ECTS 2011. Keywords: Osteoporosis, Osteopenia, Bone Mass Density, Walking Exercise, Thin women.
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Disclosure of interest: N. Habibzadeh Grant / Research Support from preventing osteoporosis. doi:10.1016/j.bone.2011.03.664
PP534-T/NIPP09 (recipient of a 2011 ECTS/IBMS Travel Award) PPAR beta-deficiency impairs muscle and skeletal response to exercise N. Bonnet a, ⁎, B. Desvergne b, S. Ferrari a a Division of Bone Diseases, Geneva University Hospital and Faculty of Medicine, Geneva, Switzerland b Center for Integrative Genomics, Faculty of Biology and Medicine, Lausanne, Switzerland Abstract: PPARβ is expressed in skeletal muscle and bone, and promotes fatty acid oxidation in response to exercise. We found that PPARβ-deficient mice have reduced muscle and bone mass and altered bone microarchitecture, which worsen with age. We investigated the influence of PPARβ on muscle and skeletal responses to exercise. Bone mass and microarchitecture were monitored in female PPARβ−/− and PPARβ+/+ mice from 16 to 21 weeks of age. Mice were subjected to moderate treadmill exercise (EXE) or untrained (UN). Relative expression of PPARβ and γ mRNA (normalized for GAPDH) was evaluated in gastrocnemius and femurs by qRT-PCR. In UN PPARβ+/+ mice, PPARβ mRNA was more abundantly expressed than PPARγ in muscle (+65% p < 0.001), but less than PPARγ in bone (− 49%, p < 0.001). Exercise modestly increased PPARβ expression (+ 16%, ns and + 38% p < 0.05 vs UN, respectively in muscle and bone) in PPARβ+/+ mice, whereas PPARγ mRNA remained unchanged. In contrast, in PPARβ−/−, exercise significantly increased PPARγ expression in muscle and bone (+ 90% and +40%, respectively, vs UN, both p < 0.05). Compared to PPARβ+/+, PPARβ−/− mice had lower maximal speed and capacity to run a long distance. However, PPARβ−/− was able to perform the moderate exercise in full. In PPARβ+/+ mice, EXE significantly increased total body (TB) lean mass (21.7 ± 0.8 vs 19.3 ± 0.3 g in UN, p < 0.05), femoral BMD (75 ± 1 vs 70 ± 0.4 mg/cm² in UN, p < 0.01), and tibial BMD (54 ± 1 vs 50 ± 0.5 mg/cm² in UN, p < 0.01). TB fat did not change significantly in response to exercise. In these mice, EXE increased trabecular BV/TV and number (TbN) at the distal femur (+ 121% and +12.6%, respectively vs UN, all p < 0.05), and similarly at the tibia. It also increased cortical bone volume (Ct.BV, 0.40 ± 0.01 vs 0.36 ± 0.01 mm 3 in UN, p < 0.05) and thickness (Ct.Th, 239 ± 9 vs 216 ± 3 μm in UN, p < 0.05) at the tibia midshaft. In contrast, in PPARβ −/− mice, EXE had no effect on TB lean mass, BMD, TbN, Ct.BV or Ct.Th either in the femur or tibia. Hence we observed a significant interaction (Pinter < 0.05 by 2F_ANOVA) between genotype and EXE/UN on these parameters. These results identify PPARβ as an important factor for the muscle and skeletal response to exercise. In absence of PPARβ, upregulation of PPARγ, particularly in bone, could further contribute to the lack of skeletal anabolic response to exercise. Whether PPARβ regulates bone modeling/remodeling through its effects on muscle and/or on bone cells is currently being investigated. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared.
doi:10.1016/j.bone.2011.03.665
PP535-S Differences in volumetric bone mineral density (vBMD) at the radius and tibia in premenopausal Caucasian and Asian women O. Hakim a, ⁎, A. Darling a, K. Hart a, J. Berry b, S. Lanham-New a a Nutritional Sciences Division, University of Surrey, Guildford, UK b Department of Medicine, University of Manchester, Manchester, UK Abstract: Current studies indicate that women of European origin have higher bone mineral density (BMD) than Far-East Asian women but few data exist on South Asian women. Roy et al. (2005) explained differences in BMD between Caucasian and Asian women by differences in bone size [1]. The aim of this study was to investigate differences between volumetric bone mineral density (vBMD) between Caucasian (C) and Asian (A) women. Thirty-five healthy premenopausal women (19 C and 16 A), age range 18–55 yrs, were studied. Peripheral Quantitative Computed Tomography (pQCT) measurements were taken at the radius and tibia (non-dominant) using a Stratec XCT 2000 pQCT scanner. Caucasians were slightly lighter and taller than Asian women, with an average BMI of 24.9 (4.12) and 27.7(5.8) respectively. The table below shows the results of vBMD at 4% and 66% radius; 4%, 14%, and 38% tibia in C and A women.
Abstracts / Bone 48 (2011) S266–S271
the quadriceps was used to induce paralysis of the right hind limb in Swiss-Webster mice; saline injection in the left side was used as control. Bone marrows from the left and right femurs were dissected after euthanasia at 0, 7, 14, 21 and 28 days post-BTX; RNAs were extracted to perform qPCR analyses. Bone loss was measured by microCT on the tibia upper extremity. On the right side, 3D measurements showed a significant decrease in bone volume as from 7 days (−31%) associated with microarchitectural changes that intensified in time (−45.9% at 21 days). Microarchitectural damages were observed from 7 days and were increased during the time course of the study. However, no significant difference in cortical thickness was observed. Expression of several bone formation factors was significantly altered as from 7 days post-BTX, such as alkaline phosphatase, TGFβ1, LRP5, sFRP2. Among them, only sFRP2 and LRP5 maintained a modified expression until 28 days post-ovariectomy. Modifications of expression of DKK1 was observed after 21 days and appeared as a late inhibitor of bone formation compared to sFRP2.Expression of bone resorption markers was increased as from 7 days and was maintained until 28 days (TRAcP, IL-6). RANKL was also increased but returned to a normal expression at 21 days. In conclusion, a localized disuse induces rapid modifications in the gene expression profile in the bone microenvironment leading to bone loss by an early decrease of bone formation factors associated with an increase in bone resorption. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.659
vitamin D status on overall health and in particular on muscle and bone function in Saudi Arabian females. The aims of this study were to: 1) determine the prevalence of hypovitaminosis D in Saudi pre and postmenopausal women; 2) investigate the effect of poor vitamin D status on physical performance. Methods: A total of 462 healthy women were recruited from the city of Jeddah through Primary Health Care Centres. Data are presented on 231 premenopausal [20–39 years]; and 231postmenopausal women [>51 years]. Menopausal grouping was confirmed by hormonal status. Fasting blood samples was collected for assessment of 25(OH)D status. Muscle function was assessed by the following tests: get up and go (GUG); 8 feet walk (8FW); five-times sit to stand (5STS). Results and discussion: Hypovitaminosis D was extensive amongst the women; with a total of 54.8% of women with 25OHD levels below <25 nmol/L (71% pre, 38.5% post), 85.1%< 50 nmol/L (93.5%pre, 76.6% post), and 95.7%< 75 nmol/L (97%pre, 94.4% post). For all women combined, a significant positive correlation was found between 25(OH)D and GUG (P< .001), 5-STS (P <.001), and 8FW (P<0.01). After adjusting for key confounding factors including BMI, the correlation remained significant for 5-STS (P <0.01). When women were classified into ‘severely deficient’ (<25 nmol/L) and ‘insufficient’ (>25 nmol/L) groups, the positive correlation between muscle function tests and 25OHD remained significant in the ‘deficiency’ group but disappeared in the ‘insufficiency’ group. When women with 25(OH)D status between 25–50 nmol/L and >50 nmol/L and >75 nmol/L were investigated, the correlations disappeared. Conclusion: These data suggest that low vitamin D status (<25 nmol/L) is not associated with poor physical performance and may be a reflection of muscle ‘adaptation’ to prolonged, life-cycle of hypovitaminosis D. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.661
PP529-S The effect of bone mineral density of distal radius exposed to vibration on rest activity of contralateral wrist flexor I. Karacan a, ⁎, M. Cidem b, C. Bahadir c, A. Rezvani a, A. Ozen d, H.I. Unalan e a Physical Medicine & Rehabilitation Dept, Bezmi Alem Vakif University, Istanbul, Turkey b Physical Medicine & Rehabilitation Dept, Danistay Healthy Center, Ankara, Turkey c Erenkoy Physical Medicine and Rehabilitation Hospital, Istanbul, Turkey d Nuclear Medicine, Bagcilar Training & Research Hospital, Istanbul, Turkey e Physical Medicine & Rehabilitation Dept, IU Cerrahpasa Medical Faculty, Istanbul, Turkey Abstract: The aim of this study was to investigate whether distal radius exposed to vibration had an effect associated with its bone mineral density (BMD) or content on the rest muscle activity of untrained-contralateral flexor carpi radialis (FCR). This study was conducted on 90 healthy adult volunteers. The rest electrical activities (EMGrms) of the right and left FCR muscle were simultaneously measured before, during and after vibration. The standardized rest-EMGrms (rest EMGrms of the left FCR / rest EMGrms of the right FCR ratio) were calculated for the left FCR muscle. The right distal radius BMD was measured by DXA. The rest-EMGrms of the untrained-left FCR muscle significantly increased during vibration. The increase in the rest-EMGrms was much more apparent in the trained-right FCR muscle than untrained-left FCR muscle during vibration. The right ultradistal radius BMD was an independent predictor for rest-EMGrms of the left FCR muscle measured during vibration. The standardized rest-EMGrms-during the vibration were significantly lower compared to standardized rest-EMGrms-preVibration and standardized restEMGrms-postVibration. The right ultradistal radius BMD was independent predictors for the standardized rest-EMGrms-during vibration. It may be suggested that radius bone exposed to cyclic mechanical loading can regulate muscle activity in the untrained-contralateral limb, based on its BMD. Keywords: Vibration, Contralateral muscle activity, Bone mineral density. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.660
PP531-T Usefulness of motor function tests in predicting new vertebral fractures K. Nawata a,b, ⁎, M. Yamauchi a, S. Takaoka a, T. Sugimoto a a Internal Medicine 1, Shimane University Faculty of Medicine, Izumo, Japan b Health and Nutrition, The University of Shimane, Matsue, Japan Abstract: Aim: Decreases in muscle strength and balance function are thought to lead to reduction of bone mineral density (BMD) and increases in the frequency of falls, and to contribute to osteoporotic fractures. Regarding the relationship between motor function tests and fracture, a longitudinal study reported that leg strength, walking speed, and leg motor coordination are useful predictive factors for hip fracture. However, no useful predictive factors have been identified for vertebral fractures. We therefore investigated the usefulness of motor function tests in predicting new vertebral fractures. Subjects and Methods: Subjects were 63 healthy postmenopausal women. BMD was measured using the DXA method at the lumbar vertebrae (L2–4) and femoral neck (FN), and the presence or absence of vertebral fractures was confirmed on X-ray. CTX, intact PTH, 25-hydoroxyvitamin D [25(OH)D] and undercarboxylated osteocalcin (ucOC) were measured. Motor function tests included standing up from chair test, tandem walk test and standing on one foot test as well as measurements of grip strength, maximum step length (MSL) and 10 mwalking speed. The presence or absence of new vertebral fractures was evaluated following a mean observation period of 2.6 years. Results: The subjects' mean values were as follows: age, 62 ± 7 years; height, 152.6 ± 5.3 cm; weight, 53.6 ± 7.9 kg; BMI, 23.0 ± 3.1 kg/m 2; L2–4 BMD, 0.87 ± 0.14 g/cm 2 (T-score, − 1.3); FN BMD, 0.64 ± 0.08 (− 1.3); CTX, 0.39 ± 0.15 ng/ mL; PTH, 43.4 ± 14.0 pg/mL; 25(OH)D, 17.2 ± 4.4 ng/mL; ucOC, 5.4 ± 3.4 ng/mL. Results on motor function tests were as follows: grip strength, 23.3 ± 3.1 kg; MSL, 107 ± 10 cm; and MSL adjusted for the length of lower limbs (% MSL), 137 ± 14%. Subjects had age-appropriate motor function. No differences based on presence or absence of new vertebral fractures were observed for BMD, CTX and 25(OH)D. On motor function tests, a significantly lower value was observed in the new vertebral fracture present group for only % MSL (present group 139 ± 14%, vs. absent group 128 ± 13%, p < 0.05). % MSL was also identified as a significant predictive factor for vertebral fracture [odds ratio, 0.92 (95%CI: 0.86–0.99), p < 0.05] following correction for age, BMI, L2–4 BMD, CTX, PTH, 25(OH)D, ucOC, presence of existing fragility fracture and observation period on logistic regression analysis. Conclusion: MSL was considered a useful factor for predicting the risk of new vertebral fractures independently of BMD, bone metabolism markers and 25(OH)D. This article is part of Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.662
PP530-M Effect of extensive hypovitaminosis D on muscle and physical performance in Saudi women K.S. Hussein a,b, ⁎, M.S.S. Ardawi c, S.L. New b, H.A. Al-kadi a a Physiology, King Abdulaziz University, Jeddah, Saudi Arabia b Nutritional Sciences, Surrey University, Guildford, UK c Clinical Biochemistry, King Abdulaziz University, Jeddah, Saudi Arabia
PP532-S Evaluation of the bone status in high level cyclists G. Guillaume a, D. Chappard b, M. Audran c, ⁎ a Institut du Sport, Paris, France b IRIS -IBS Institut de Biologie en Santé, INSERM, U922-LHEA, France c CHU ANGERS, Rheumatology Unit, Angers, France
Introduction and aims: Vitamin D deficiency, which is common among elderly people, is associated with reduced muscle strength. Few data exist, however, on the implications of poor
Abstract: The effects of physical exercise and sport on bone mass have been the subject of many studies, the results of which are largely determined by the type of exercise. It was thus
Abstracts / Bone 48 (2011) S266–S271 observed that the sports that generate weight bearing, with repeated impact loading have a more favorable effect than sports activities that do not, like swimming or cycling. Aim: We report the results of measurements of bone mineral density as well as biological parameters in professional cyclists of high level, subjected to regular training and tough competitions. Patients, methods: 29 professional runners were studied (aged 26.5± 5.3 yrs; BMI: 21.7± 1.6 kg/m 2; seniority in the occupation: 4.5 ±4 yrs; traversed annual distance 27933 ± 2626 km). Bone density measurements (BMD) were performed in 20 cyclists in the same center of densitometry using a Hologic Discovery C device at the lumbar, femoral (total and trans-cervical) and radial sites. Values were expressed as Z-score according to the reference data given by the manufacturer, Hologic (USA). Biological parameters related to bone metabolism were obtained in 29 cyclists: serum calcium, phosphate, creatinine, alkaline phosphatase (AP), serum osteocalcin (OC), 25(OH)vit.D, testosterone, IGF-1, TSH. Results: BMD data (Z-score) are given below. Five runners had a low lumbar BMD. Mean BMD Z-score was −1.21 ±.42 at the femoral neck −1.22± .21 at the total femur. The lowest values of BMD were measured at the mid radius site: mean Z score −1.77 ± .78 (Fig. 1). In 29 cyclists serum calcium and kidney function were in the normal range. Biochemical parameters of bone formation (OC, AP) were normal; individual values of 25(OH)vit.D ranged from 29 to 143 mmol/l (mean: 74 mmol/l). A significant inverse relationship was found between IGF-1 and lumbar BMD. Conclusion: We observed in highly trained professional master cyclists,
Image/Graph
Fig. 1.
low BMD at different sites. With the increased risk of severe falls, our data underline the need to pay greater attention to the bone status of these high level athletes. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared.
doi:10.1016/j.bone.2011.03.663
PP533-M The effect of walking exercise on bone mass density in young thin women with osteopenia N. Habibzadeh ⁎ Department of Sport Sciences, University of Guilan, Rasht, Islamic Republic of Iran
Abstract: Osteoporosis is a widespread disorder for women, that causes bone fractures after simple trauma in them. But exercise is long being known to reduce the risk of osteoporosis. Therefore this study aims to investigate the effect of walking program on bone mass density in order to reduce bone loss and osteoporosis in thin young women. Twenty thin (BM I < 20) osteopenic women with age 22.00 ± 1.50 years volunteered to participate in this study. Then they were randomly assigned to exercise (n = 10) and control (n = 10) groups. Before and after the training program both groups had anthropometric measurements, blood analysis. Bone mass density was evaluated by using dual-energy X-ray absorptiometry (DXA) at hip and spin (L2–L4). Each walking session was 30 min walking at 50–75% of maximal heart rate, 3 days per week, for 2 months. After 2 months, exercise group had no effect assignment on BMD at the spin (L2–L4) and hip (p > 0.05). However they experienced slight increase in BMD at both regions, while the control group did not. Also no change was observed in bloods factors (p > 0.05). Percent body fat, fat mass and lean mass changes in response to training were significant in the exercise group (all p = 0.000).This study demonstrated that walking exercise may have reduced the risk of bone loss, even though it did not significantly increase bone density .However further studies are needed to evaluate the effect of walking exercise on BMD and the risk of osteoporosis in thin osteopenic women. This article is part of a Special Issue entitled ECTS 2011. Keywords: Osteoporosis, Osteopenia, Bone Mass Density, Walking Exercise, Thin women.
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Disclosure of interest: N. Habibzadeh Grant / Research Support from preventing osteoporosis. doi:10.1016/j.bone.2011.03.664
PP534-T/NIPP09 (recipient of a 2011 ECTS/IBMS Travel Award) PPAR beta-deficiency impairs muscle and skeletal response to exercise N. Bonnet a, ⁎, B. Desvergne b, S. Ferrari a a Division of Bone Diseases, Geneva University Hospital and Faculty of Medicine, Geneva, Switzerland b Center for Integrative Genomics, Faculty of Biology and Medicine, Lausanne, Switzerland Abstract: PPARβ is expressed in skeletal muscle and bone, and promotes fatty acid oxidation in response to exercise. We found that PPARβ-deficient mice have reduced muscle and bone mass and altered bone microarchitecture, which worsen with age. We investigated the influence of PPARβ on muscle and skeletal responses to exercise. Bone mass and microarchitecture were monitored in female PPARβ−/− and PPARβ+/+ mice from 16 to 21 weeks of age. Mice were subjected to moderate treadmill exercise (EXE) or untrained (UN). Relative expression of PPARβ and γ mRNA (normalized for GAPDH) was evaluated in gastrocnemius and femurs by qRT-PCR. In UN PPARβ+/+ mice, PPARβ mRNA was more abundantly expressed than PPARγ in muscle (+65% p < 0.001), but less than PPARγ in bone (− 49%, p < 0.001). Exercise modestly increased PPARβ expression (+ 16%, ns and + 38% p < 0.05 vs UN, respectively in muscle and bone) in PPARβ+/+ mice, whereas PPARγ mRNA remained unchanged. In contrast, in PPARβ−/−, exercise significantly increased PPARγ expression in muscle and bone (+ 90% and +40%, respectively, vs UN, both p < 0.05). Compared to PPARβ+/+, PPARβ−/− mice had lower maximal speed and capacity to run a long distance. However, PPARβ−/− was able to perform the moderate exercise in full. In PPARβ+/+ mice, EXE significantly increased total body (TB) lean mass (21.7 ± 0.8 vs 19.3 ± 0.3 g in UN, p < 0.05), femoral BMD (75 ± 1 vs 70 ± 0.4 mg/cm² in UN, p < 0.01), and tibial BMD (54 ± 1 vs 50 ± 0.5 mg/cm² in UN, p < 0.01). TB fat did not change significantly in response to exercise. In these mice, EXE increased trabecular BV/TV and number (TbN) at the distal femur (+ 121% and +12.6%, respectively vs UN, all p < 0.05), and similarly at the tibia. It also increased cortical bone volume (Ct.BV, 0.40 ± 0.01 vs 0.36 ± 0.01 mm 3 in UN, p < 0.05) and thickness (Ct.Th, 239 ± 9 vs 216 ± 3 μm in UN, p < 0.05) at the tibia midshaft. In contrast, in PPARβ −/− mice, EXE had no effect on TB lean mass, BMD, TbN, Ct.BV or Ct.Th either in the femur or tibia. Hence we observed a significant interaction (Pinter < 0.05 by 2F_ANOVA) between genotype and EXE/UN on these parameters. These results identify PPARβ as an important factor for the muscle and skeletal response to exercise. In absence of PPARβ, upregulation of PPARγ, particularly in bone, could further contribute to the lack of skeletal anabolic response to exercise. Whether PPARβ regulates bone modeling/remodeling through its effects on muscle and/or on bone cells is currently being investigated. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared.
doi:10.1016/j.bone.2011.03.665
PP535-S Differences in volumetric bone mineral density (vBMD) at the radius and tibia in premenopausal Caucasian and Asian women O. Hakim a, ⁎, A. Darling a, K. Hart a, J. Berry b, S. Lanham-New a a Nutritional Sciences Division, University of Surrey, Guildford, UK b Department of Medicine, University of Manchester, Manchester, UK Abstract: Current studies indicate that women of European origin have higher bone mineral density (BMD) than Far-East Asian women but few data exist on South Asian women. Roy et al. (2005) explained differences in BMD between Caucasian and Asian women by differences in bone size [1]. The aim of this study was to investigate differences between volumetric bone mineral density (vBMD) between Caucasian (C) and Asian (A) women. Thirty-five healthy premenopausal women (19 C and 16 A), age range 18–55 yrs, were studied. Peripheral Quantitative Computed Tomography (pQCT) measurements were taken at the radius and tibia (non-dominant) using a Stratec XCT 2000 pQCT scanner. Caucasians were slightly lighter and taller than Asian women, with an average BMI of 24.9 (4.12) and 27.7(5.8) respectively. The table below shows the results of vBMD at 4% and 66% radius; 4%, 14%, and 38% tibia in C and A women.