| 1. |
- Alsafi, Zahraa, et al.
(författare)
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Myocardial performance index in female athletes.
- 2017
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Ingår i: Cardiovascular Ultrasound. - : BioMed Central. - 1476-7120. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- Background: Long-term intensive training leads to morphological and mechanical changes in the heart generally known as “athlete’s heart”. Previous studies have suggested that the diastolic and systolic function of the ventricles is unaltered in athletes compared to sedentary. The purpose of this study was to investigate myocardial performance index (MPI) by pulsed wave Doppler (PWD) and by tissue Doppler imaging (TDI) in female elite athletes compared to sedentary controls. Methods: The study consisted of 32 athletes (mean age 20 ± 2 years) and 34 sedentary controls (mean age 23 ± 2 years). MPI by PWD and TDI were measured in the left (LV) and right ventricle (RV) in both groups. Moreover, comparisons of MPI by the two methods and between the LV and RV within the two groups were made. Results: There were no significant differences in MPI between athletes and controls (p > 0.05), whereas the LV had significantly higher MPI compared to RV (p < 0.001, in athletes and controls). The agreement and the correlation between the two methods measuring MPI showed low agreement and no correlation (athletes RV r = −0.027, LV r = 0.12; controls RV r = 0.20, LV r = 0.30). Conclusion: The global function of the LV and RV measured by MPI with PWD and TDI is similar in female athletes compared to sedentary controls. Conversely, both MPI by PWD and by TDI shows a significant difference between the LV and RV. However, the agreement and correlation between conventional methods of measuring MPI by PWD compared to MPI by TDI is very poor in both these populations.
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| 2. |
- Alwis, Gayani, et al.
(författare)
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A 2-year school-based exercise programme in pre-pubertal boys induces skeletal benefits in lumbar spine.
- 2008
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Ingår i: Acta Pædiatrica. - : Wiley. - 1651-2227 .- 0803-5253. ; 97, s. 1564-1571
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Tidskriftsartikel (refereegranskat)abstract
- Aim: The aim of this study was to evaluate if a general school-based exercise intervention programme in pre-pubertal boys would render site-specific benefits in bone mineral accrual and gain in femoral neck structure. Methods: Eighty boys aged 7-9 years were included in a curriculum-based exercise intervention programme comprising 40 min of general physical activity per school day (200 min/week) for 2 years. Fifty-seven age-matched boys, assigned to the general Swedish school curriculum of 60 min/week, served as controls. Bone mineral content was measured with dual X-ray absorptiometry of the total body, the third lumbar vertebra and hip. Specific software, the hip structural analyses, evaluated the structural properties of the femoral neck. Annual changes were compared. The level of physical activity was estimated through questionnaires and accelerometers. Results: The mean annual bone mineral content gain in third lumbar vertebra was 3.0 percentage points (p < 0.01) and in width 1.3 percentage points (p < 0.01) greater in the intervention than in the control group. The weekly duration of exercise estimated through the questionnaire correlated with gain in bone mineral content in third lumbar vertebra (r = 0.25, p = 0.005) and vertebra width (r = 0.20, p = 0.02). Conclusion: A school-based exercise intervention programme in pre-pubertal boys enhances the skeletal benefits at lumbar spine.
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| 3. |
- Alwis, Gayani, et al.
(författare)
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A school-curriculum-based exercise intervention program for two years in pre-pubertal girls does not influence hip structure.
- 2008
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Ingår i: Dynamic Medicine. - : Springer Science and Business Media LLC. - 1476-5918. ; 7, s. 8-8
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT: BACKGROUND: It is known that physical activity during growth has a positive influence on bone mineral accrual, and is thus possibly one strategy to prevent osteoporosis. However, as bone geometry, independent of areal bone mineral density (aBMD), influences fracture risk, this study aimed to evaluate whether hip structure in pre-pubertal girls is also affected by a two-year exercise intervention program. METHODS: Forty-two girls aged 7-9 years in a school-curriculum-based exercise intervention program comprising 40 minutes of general physical activity per school day (200 minutes per week) were compared with 43 age-matched girls who participated in the general Swedish physical education curriculum comprising a mean of 60 minutes per week. The hip was scanned by dual energy X-ray absorptiometry (DXA) and the hip structural analysis (HSA) software was applied to evaluate bone mineral content (BMC, g), areal bone mineral density (aBMD, g/cm2), periosteal diameter, cross-sectional area (CSA, cm2), section modulus (Z, cm3) and cross-sectional moment of inertia (CSMI, cm4) of the femoral neck (FN). Annual changes were compared. Subjective duration of physical activity was estimated by questionnaire and objective level of everyday physical activity at follow-up by means of accelerometers worn for four consecutive days. All children remained at Tanner stage 1 throughout the study. Group comparisons were made by independent student's t-test between means and analyses of covariance (ANCOVA). RESULTS: At baseline, the two groups did not differ with regard to age, anthropometrics or bone parameters. No between-group differences were observed for annual changes in the FN variables measured. CONCLUSION: A two-year school-based moderately intense general exercise program for 7-9-year-old pre-pubertal girls does not influence structural changes in the FN.
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| 4. |
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| 5. |
- Arvidsson, Daniel, 1974, et al.
(författare)
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A Longitudinal Analysis of the Relationships of Physical Activity and Body Fat With Nerve Growth Factor and Brain-Derived Neural Factor in Children
- 2018
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Ingår i: Journal of Physical Activity & Health. - : Human Kinetics. - 1543-3080 .- 1543-5474. ; 15:8, s. 620-625
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Tidskriftsartikel (refereegranskat)abstract
- Background: Nerve growth factor (NGF) and brain-derived neural factor (BDNF) are important for brain function and detectable in the blood. This study explored the longitudinal associations of physical activity and body fat with serum NGF and BDNF in children. Methods: Two waves of measurements were performed 2 years apart in 8- to 11-year-old children, including physical activity using the ActiGraph model 7164, body composition by dual-energy X-ray absorptiometry, and serum NGF and BDNF determined by multiplex immunoassay. The first wave included 248 children. Full information maximum likelihood estimation with robust standard errors was applied in structural equation modeling. Results: Vigorous physical activity showed a direct positive longitudinal relationship with NGF (standardized coefficient beta = 0.30, P = .01) but not with BDNF (beta = 0.04, P = .84). At the same time, body fat percentage was positively related to both NGF (beta = 0.59, P < .001) and BDNF (beta = 0.17, P = .04). There was an indication of an indirect relationship of vigorous physical activity with NGF (product of unstandardized coefficient beta = -0.18, P = .02) and BDNF (beta = -0.07, P = .05) through the negative relationship with body fat percentage (beta = -0.36, P < .001). Conclusions: Vigorous physical activity is directly related to serum NGF and indirectly through the level of body fat. The relationships with serum BDNF are more complex.
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| 6. |
- Buttazzoni, Christian, et al.
(författare)
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A Pediatric Bone Mass Scan has Poor Ability to Predict Peak Bone Mass: An 11-Year Prospective Study in 121 Children.
- 2015
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Ingår i: Calcified Tissue International. - : Springer Science and Business Media LLC. - 1432-0827 .- 0171-967X. ; 96:5, s. 379-388
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Tidskriftsartikel (refereegranskat)abstract
- This 11-year prospective longitudinal study examined how a pre-pubertal pediatric bone mass scan predicts peak bone mass. We measured bone mineral content (BMC; g), bone mineral density (BMD; g/cm(2)), and bone area (cm(2)) in femoral neck, total body and lumbar spine by dual-energy X-ray absorptiometry in a population-based cohort including 65 boys and 56 girls. At baseline all participants were pre-pubertal with a mean age of 8 years (range 6-9), they were re-measured at a mean 11 years (range 10-12) later. The participants were then mean 19 years (range 18-19), an age range that corresponds to peak bone mass in femoral neck in our population. We calculated individual BMC, BMD, and bone size Z scores, using all participants at each measurement as reference and evaluated correlations between the two measurements. Individual Z scores were also stratified in quartiles to register movements between quartiles from pre-pubertal age to peak bone mass. The correlation coefficients (r) between pre-pubertal and young adulthood measurements for femoral neck BMC, BMD, and bone area varied between 0.37 and 0.65. The reached BMC value at age 8 years explained 42 % of the variance in the BMC peak value; the corresponding values for BMD were 31 % and bone area 14 %. Among the participants with femoral neck BMD in the lowest childhood quartile, 52 % had left this quartile at peak bone mass. A pediatric bone scan with a femoral neck BMD value in the lowest quartile had a sensitivity of 47 % [95 % confidence interval (CI) 28, 66] and a specificity of 82 % (95 % CI 72, 89) to identify individuals who would remain in the lowest quartile at peak bone mass. The pre-pubertal femoral neck BMD explained only 31 % of the variance in femoral neck peak bone mass. A pre-pubertal BMD scan in a population-based sample has poor ability to predict individuals who are at risk of low peak bone mass.
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| 7. |
- Cöster, Marcus E., et al.
(författare)
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Effects of an 8-year childhood physical activity intervention on musculoskeletal gains and fracture risk
- 2016
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Ingår i: Bone. - : Elsevier BV. - 8756-3282. ; 93, s. 139-145
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Tidskriftsartikel (refereegranskat)abstract
- Background Physical activity (PA) in childhood is associated with musculoskeletal benefits while the effect on fracture risk is yet to be determined. The aim of this study was to evaluate whether extension of a PA intervention leads to improvement in musculoskeletal traits with an accompanied reduced fracture risk. We hypothesized that the PA program would have beneficial effects in both sexes, but more so in girls since they tend to be less physically active than boys during this time frame. Methods In one elementary school we increased physical education (PE) from 60 to 200 min per school week and followed 65 girls and 93 boys from a mean age of 7 years until a mean age of 15 years. Thirty-nine girls and 37 boys in three other schools continued with 60 min of PE per week during the same years and served as controls. We measured bone mineral content (BMC), areal bone mineral density (aBMD), and bone area annually with dual energy X-ray absorptiometry, and leg muscle strength with a computerized dynamometer. In 3534 children within the same PE program (1339 in the intervention and 2195 in the control group) we registered incident fractures during the 8-year study period and estimated annual sex-specific fracture incidence rate ratios (IRRs). Results Girls in the intervention group annually gained more total body less head aBMD, spine aBMD (p < 0.01), femoral neck BMC (p < 0.05), lumbar vertebrae size (p < 0.05), and knee flexion strength (p < 0.05) than girls in the control cohort. In boys we found no group differences. There was an inverse correlation between number of years with extra PE and the annual IRR of sustaining fractures in both girls (r = − 0.90 (95% CI − 0.98 to − 0.51); p < 0.001) and boys (r = − 0.74 (95% CI − 0.94 to − 0.02); p < 0.05). Conclusion In this 8-year pediatric school-based moderate exercise intervention program there is an inverse correlation in both sexes between annual IRR and each additional year of extra PA. A sub-cohort of girls in the intervention group had greater gains in bone mass, bone size, and muscle strength, which could possibly explain the inverse correlation between years within the PA program and fracture risk, while in boys the reason for the inverse correlation remains unknown. It should be noted that differences in unreported factors such as skeletal maturity status, diet, and spare time PA could confound our inferences. That is, true causality cannot be stated.
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| 8. |
- Cöster, Marcus E., et al.
(författare)
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How does a physical activity programme in elementary school affect fracture risk? : A prospective controlled intervention study in Malmo, Sweden
- 2017
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Ingår i: BMJ Open. - : BMJ. - 2044-6055. ; 7:2
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Recent evidence from the 7-year followup of the Pediatric Osteoporosis Prevention (POP) study indicates an inverse correlation between years of participation in a physical activity (PA) intervention and fracture risk in children. However, we could not see a statistically significant reduction in fracture risk, which urged for an extension of the intervention. Setting: The study was conducted in 4 neighbouring elementary schools, where 1 school functioned as intervention school. Participants: We included all children who began first grade in these 4 schools between 1998 and 2012. This resulted in 1339 children in the intervention group and 2195 children in the control group, all aged 6-8 years at the state of the study. Intervention: We launched an 8-year intervention programme with 40 min of moderate PA per school day, while the controls continued with the Swedish national standard of 60 min of PA per week. Primary outcome measure: We used the regional radiographic archive to register objectively verified fractures and we estimated annual fracture incidences and incidence rate ratios (IRRs). Results: During the first year after initiation of the intervention, the fracture IRR was 1.65 (1.05 to 2.08) (mean 95% CI). For each year of the study, the fracture incidence rate in the control group compared with the intervention group increased by 15.7% (5.6% to 26.8%) (mean 95% CI). After 8 years, the IRR of fractures was 52% lower in the intervention group than in the control group (IRR 0.48 (0.25 to 0.91) (mean 95% CI))]. Conclusions: Introduction of the school-based intervention programme is associated with a higher fracture risk in the intervention group during the first year followed by a gradual reduction, so that during the eighth year, the fracture risk was lower in the intervention group.
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| 9. |
- Danielson, Anton, et al.
(författare)
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School-based study found that physical activity and aerobic fitness predicted increases in total body fat and abdominal fat at a mean age of 9.8 years.
- 2018
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Ingår i: Acta Pædiatrica. - : Wiley. - 1651-2227 .- 0803-5253. ; 107:10, s. 1810-1817
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Tidskriftsartikel (refereegranskat)abstract
- AIM: We assessed whether baseline measurements of physical activity, aerobic fitness, body fat and abdominal fat were predictors of changes in body fat measurements over a two-year period.METHODS: The study comprised of 204 children aged 9.8 ± 0.6 years with a normal body mass distribution, who recruited from four schools in middle-class areas of Malmö, Sweden, from 2001 to 2004. Peak oxygen uptake and physical activity were measured at baseline. Body fat was measured by dual-energy X-ray absorptiometry at baseline and two years later.RESULTS: Physical activity, aerobic fitness and total body fat or abdominal fat were predictors of change in total body fat or abdominal fat over a period of two years. Changes in the percentage of body fat were not related to any of the baseline measurements.CONCLUSION: Our two-year follow-up of children with a mean age of 9.8 years at baseline showed that physical activity, aerobic fitness and body fat or abdominal fat predicted changes in total body fat or abdominal fat, but not the percentage of body fat.
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| 10. |
- Dencker, Magnus, et al.
(författare)
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Aerobic fitness related to cardiovascular risk factors in young children.
- 2012
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Ingår i: European Journal of Pediatrics. - : Springer Science and Business Media LLC. - 1432-1076 .- 0340-6199. ; 171:4, s. 705-710
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Tidskriftsartikel (refereegranskat)abstract
- Low aerobic fitness (maximum oxygen uptake (VO(2PEAK))) is predictive for poor health in adults. In a cross-sectional study, we assessed if VO(2PEAK) is related to a composite risk factor score for cardiovascular disease (CVD) in 243 children (136 boys and 107 girls) aged 8 to 11 years. VO(2PEAK) was assessed by indirect calorimetry during a maximal exercise test and scaled by body mass (milliliters per minute per kilogram). Total body fat mass (TBF) and abdominal fat mass (AFM) were measured by Dual-energy X-ray absorptiometry. Total body fat was expressed as a percentage of total body mass (BF%) and body fat distribution as AFM/TBF. Systolic and diastolic blood pressure (SDP and DBP) and resting heart rate (RHR) were measured. The mean artery pressure (MAP) and pulse pressure (PP) were calculated. Echocardiography, 2D-guided M-mode, was performed. Left atrial diameter (LA) was measured and left ventricular mass (LVM) and relative wall thickness (RWT) were calculated. Z scores (value for the individual - mean value for group)/SD were calculated by sex. The sum of z scores for DBP, SDP, PP, MAP, RHR, LVM, LA, RWT, BF%, AFM and AFM/TBF were calculated in boys and girls, separately, and used as composite risk factor score for CVD. Pearson correlation revealed significant associations between VO(2PEAK) and composite risk factor score in both boys (r = -0.48 P < 0.05) and in girls (r = -0.42, P < 0.05). One-way ANOVA analysis indicated significant differences in composite risk factor score between the different quartiles of VO(2PEAK) (P < 0.001); thus, higher VO(2PEAK) was associated with lower composite risk factor score for CVD. In conclusion, low VO(2PEAK) is associated with an elevated composite risk factor score for CVD in both young boys and girls.
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