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1.
Osteoporos Int ; 32(3): 451-465, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32935171

RESUMEN

Our aim was to explore change in kyphosis and vertebral fracture incidence following 8 months of high-intensity resistance and impact training (HiRIT) or machine-based isometric axial compression (IAC) training in men with osteopenia and osteoporosis. HiRIT and IAC improved posture. HiRIT participants did not experience progression or incident vertebral fracture. IAC participants did experience progression and incident vertebral fracture. INTRODUCTION: The Lifting Intervention For Training Muscle and Osteoporosis Rehabilitation for Men (LIFTMOR-M) trial examined efficacy and safety of an eight-month, supervised, high-intensity progressive resistance and impact training (HiRIT) program compared with machine-based isometric axial compression (IAC) training in middle-aged and older men with low areal bone mineral density (aBMD). The primary purpose of the current work was to explore change in thoracic kyphosis and incident fracture from vertebral morphology following eight-months of HiRIT or IAC training. The secondary purpose was to explore change in clinical kyphosis measures for HiRIT, IAC and a non-randomized, matched control group. METHODS: Men (≥ 45 yrs), with low aBMD, were recruited and randomized to HiRIT or IAC, or designated control. Clinical measures of thoracic kyphosis with inclinometry were determined. Cobb angle of kyphosis and vertebral fracture assessment using the Genant semi-quantitative method were determined from lateral thoracolumbar DXA (Medix DR, Medilink, France). Per-protocol (n = 40) and intention-to-treat (n = 93) analyses were conducted. RESULTS: Forty participants (HiRIT n = 20, IAC n = 20; 66.1 ± 7.8 yrs.; lumbar spine T-score - 0.1 ± 0.8; femoral neck T-score - 1.5 ± 0.5) underwent clinical kyphosis measures and thoracolumbar DXA at baseline and follow-up. No between-group differences were detected in kyphosis change, however, within-group improvements in neutral (HiRIT - 2.3 ± 0.8°; IAC - 2.5 ± 0.8°) and 'standing tall' (HiRIT - 2.4 ± 0.8°; IAC - 2.0 ± 0.8°) postures were observed (p < 0.05). HiRIT improved Cobb angle (- 3.5 ± 1.5°, p = 0.027) from baseline. Over the 8 months, no incident vertebral fractures nor progression of prevalent vertebral fractures occurred for HiRIT participants. Five incident fractures of thoracic vertebrae occurred for IAC and one wedge fracture progressed. Ninety-three participants underwent clinical kyphosis measures at both time-points (HiRIT n = 34, IAC n = 33, control n = 26). HiRIT exhibited a reduction in 'standing tall' kyphosis compared to control (- 2.3 ± 0.6° versus 1.4 ± 0.7°, p < 0.05), but no other between-group differences were detected. CONCLUSIONS: Although there was no difference in change between intervention groups, thoracic kyphosis appeared to improve in both HiRIT and IAC with exercise exposure. HiRIT improved 'standing tall' posture in comparison to usual activities. HiRIT was not associated with vertebral fracture progression or incident vertebral fracture, but for some IAC participants there was evidence of progression of vertebral fracture severity and incident vertebral fractures, in our small sample. Larger trials are required to confirm the observations of the current work, which was exploratory in nature.


Asunto(s)
Enfermedades Óseas Metabólicas , Cifosis , Osteoporosis , Fracturas de la Columna Vertebral , Anciano , Enfermedades Óseas Metabólicas/etiología , Francia , Humanos , Cifosis/complicaciones , Vértebras Lumbares/lesiones , Masculino , Persona de Mediana Edad , Músculos , Osteoporosis/etiología , Fracturas de la Columna Vertebral/etiología , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/lesiones
2.
Osteoporos Int ; 30(5): 957-964, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30612163

RESUMEN

Our aim was to assess risk of vertebral fracture during high-intensity resistance and impact training (HiRIT) for postmenopausal women with low bone mass. HiRIT did not induce vertebral fracture, as evidenced by a reduction in kyphosis following 8 months of training and a lack of change in vertebral morphology. INTRODUCTION: The LIFTMOR trial demonstrated a novel, HiRIT program notably improved bone mass in postmenopausal women with osteopenia and osteoporosis. While no clinical signs or symptoms of vertebral crush fracture were evident during the trial, anecdotal feedback suggests that concerns about safety of HiRIT in the osteoporosis demographic remain. The aim of the current work was to assess vertebral body morphology, Cobb angle, and clinical measures of thoracic kyphosis in participants in the LIFTMOR trial for evidence of vertebral fracture following 8 months of supervised HiRIT. METHODS: Participants were randomized to either 8 months of 30-min, twice-weekly, supervised HiRIT or unsupervised, low-intensity, home-based exercise (CON). Lateral thoracolumbar DXA scans (Medix DR, Medilink, France) were performed at baseline and follow-up. Cobb angle was determined, and vertebral fracture identification was performed using the semiquantitative Genant method. Clinical kyphosis measurements were performed in relaxed standing (neutral posture) and standing tall using an inclinometer and a flexicurve. RESULTS: The HiRIT group exhibited a reduction in inclinometer-determined standing tall thoracic kyphosis compared to CON (- 6.7 ± 8.2° vs - 1.6 ± 8.1°, p = 0.031). Both the HiRIT and CON groups exhibited within-group improvement in kyphosis in relaxed standing as measured by both inclinometer and flexicurve (p < 0.05). There were no changes in vertebral fracture classification in the HiRIT group post-intervention. A single, new, wedge deformity was observed for CON. CONCLUSIONS: Supervised HiRIT was not associated with an increased risk of vertebral fracture in postmenopausal women with low bone mass. Indeed, a clinically relevant improvement in thoracic kyphosis was observed following 8 months of supervised HiRIT, further supporting its efficacy as an osteoporosis intervention for postmenopausal women with low to very low bone mass.


Asunto(s)
Terapia por Ejercicio/efectos adversos , Cifosis/rehabilitación , Osteoporosis Posmenopáusica/rehabilitación , Fracturas Osteoporóticas/etiología , Fracturas de la Columna Vertebral/etiología , Absorciometría de Fotón , Anciano , Estatura/fisiología , Densidad Ósea/fisiología , Terapia por Ejercicio/métodos , Femenino , Humanos , Cifosis/etiología , Cifosis/fisiopatología , Vértebras Lumbares/lesiones , Persona de Mediana Edad , Osteoporosis Posmenopáusica/complicaciones , Fracturas Osteoporóticas/fisiopatología , Entrenamiento de Fuerza/efectos adversos , Entrenamiento de Fuerza/métodos , Medición de Riesgo/métodos , Método Simple Ciego , Fracturas de la Columna Vertebral/fisiopatología , Vértebras Torácicas/lesiones
3.
Bone Joint Res ; 5(11): 538-543, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27827803

RESUMEN

OBJECTIVES: The aim of the current study was to assess whether calcaneal broadband ultrasound attenuation (BUA) can predict whole body and regional dual-energy x-ray absorptiometry (DXA)-derived bone mass in healthy, Australian children and adolescents at different stages of maturity. METHODS: A total of 389 boys and girls across a wide age range (four to 18 years) volunteered to participate. The estimated age of peak height velocity (APHV) was used to classify children into pre-, peri-, and post-APHV groups. BUA was measured at the non-dominant heel with quantitative ultrasonometry (QUS) (Lunar Achilles Insight, GE), while bone mineral density (BMD) and bone mineral content (BMC) were examined at the femoral neck, lumbar spine and whole body (DXA, XR-800, Norland). Associations between BUA and DXA-derived measures were examined with Pearson correlations and linear regression. Participants were additionally ranked in quartiles for QUS and DXA measures in order to determine agreement in rankings. RESULTS: For the whole sample, BUA predicted 29% of the study population variance in whole body BMC and BMD, 23% to 24% of the study population variance in lumbar spine BMC and BMD, and 21% to 24% of the variance in femoral neck BMC and BMD (p < 0.001). BUA predictions were strongest for the most mature participants (pre-APHV R2 = 0.03 to 0.19; peri-APHV R2 = 0.05 to 0.17; post-APHV R2 = 0.18 to 0.28) and marginally stronger for girls (R2 = 0.25-0.32, p < 0.001) than for boys (R2 = 0.21-0.27, p < 0.001). Agreement in quartile rankings between QUS and DXA measures of bone mass was generally poor (27.3% to 38.2%). CONCLUSION: Calcaneal BUA has a weak to moderate relationship with DXA measurements of bone mass in children, and has a tendency to misclassify children on the basis of quartile rankings.Cite this article: B. K. Weeks, R. Hirsch, R. C. Nogueira, B. R. Beck. Is calcaneal broadband ultrasound attenuation a valid index of dual-energy x-ray absorptiometry-derived bone mass in children? Bone Joint Res 2016;5:538-543. DOI: 10.1302/2046-3758.511.BJR-2016-0116.R1.

4.
5.
Osteoporos Int ; 26(12): 2889-94, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26243363

RESUMEN

UNLABELLED: The aim of the LIFTMOR (Lifting Intervention For Training Muscle and Osteoporosis Rehabilitation) trial is to determine the safety and efficacy of brief, bone-targeted, high-intensity progressive resistance training (HiPRT) with impact loading for postmenopausal women with low bone mass. Preliminary findings indicate the LIFTMOR program is safe and effective. INTRODUCTION: Despite a lack of notable efficacy, exercise guidelines for osteoporosis typically recommend moderate-intensity exercises, owing to a perceived risk of fracture from high-intensity loading. Indeed, safety concerns alone have prevented the well-recognised preferential response of bone tissue to high-intensity loads from being applied to those who stand to benefit the most. To progress from this therapeutic stalemate, a challenge to conventional wisdom was required. Our goal was to examine the safety and efficacy of HiPRT and impact loading for risk factors of osteoporotic fracture in postmenopausal women with low to very low bone mass. METHODS: Participants have been randomised to either 8 months of twice-weekly 30-min supervised HiPRT and impact loading or a low-intensity home-based exercise program of the same duration and dose. Testing at baseline and follow-up has included anthropometry; bone, muscle, and fat mass; and functional performance. RESULTS: Twenty-eight women (66.1 ± 4.8 years, mean lumbar spine T-score -2.15 ± 0.72) have completed the study. HiPRT and impact loading (n = 12) improved height (0.4 ± 0.2 cm vs -0.3 ± 0.1 cm, p = 0.003), femoral neck bone mineral density (0.3 ± 0.5 % vs -2.5 ± 0.8 %, p = 0.016), lumbar spine bone mineral density (1.6 ± 0.9 % vs -1.7 ± 0.6 %, p = 0.005), and functional performance (p < 0.05), compared to controls (n = 16). Compliance has been >87 %. There have been no injuries. CONCLUSIONS: Brief supervised HiPRT with impact loading is a safe and effective exercise therapy for postmenopausal women with low to very low bone mass.


Asunto(s)
Osteoporosis Posmenopáusica/rehabilitación , Entrenamiento de Fuerza/métodos , Anciano , Antropometría/métodos , Composición Corporal/fisiología , Densidad Ósea/fisiología , Terapia por Ejercicio/métodos , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/fisiopatología , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/prevención & control , Cooperación del Paciente/estadística & datos numéricos , Entrenamiento de Fuerza/efectos adversos , Factores de Riesgo , Método Simple Ciego
6.
Int J Sports Med ; 35(11): 900-5, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24886922

RESUMEN

The purpose of the current study was to determine the relationships between lifetime physical activity participation, neuromuscular performance and body composition in men at musculoskeletal maturity. 50 healthy men (age 25.2±4.5 years) volunteered to participate. Lifetime physical activity was determined from the Bone-specific Physical Activity Questionnaire. Impulse generated during a maximal vertical jump was calculated as an index of neuromuscular performance. Bone mineral density (BMD), lean and fat mass were determined from dual-energy x-ray absorptiometry (XR800, Norland). A subsample of participants (n=13) additionally underwent peripheral quantitative computed tomography (pQCT, XCT3000, Stratec) measures. Results demonstrated that those in the highest tertile for lifetime physical activity exhibited the greatest lumbar spine BMD (µdiff=0.12 g/cm2, p=0.005) and lean body mass index (LBMI) (p=0.04). Those in the highest tertile for impulse also exhibited the highest whole body (µdiff=0.08 g/cm2), lumbar spine (µdiff=0.14 g/cm2), and femoral neck BMD (µdiff=0.15 g/cm2) (p≤0.05). All BMD differences exceeded the least significant change. Childhood physical activity was positively related to LBMI (r=0.28, p=0.05), whereas sedentary activity was inversely related to femoral neck BMD (r=-0.33, p=0.02). Results support recommendations for sustained physical activity participation during the growing years.


Asunto(s)
Envejecimiento/fisiología , Composición Corporal , Ejercicio Físico/fisiología , Músculo Esquelético/fisiología , Adulto , Índice de Masa Corporal , Densidad Ósea , Humanos , Masculino , Músculo Esquelético/inervación , Adulto Joven
7.
Pediatr Obes ; 7(3): 196-204, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22434783

RESUMEN

OBJECTIVE: To determine the effect of a twice-weekly, school-based, 10-min jumping regime on muscle and fat tissue in healthy adolescent boys and girls. METHODS: We replaced regular warm-up activities with jumping in physical education (PE) classes of early high school students for 8 months to observe the effect on muscle and fat tissue. A total of 99 adolescents (46 boys, 53 girls; 13.8 ± 0.4 years) volunteered to participate. Intervention group subjects performed 10 min of varied jumping activity, while control subjects performed a regular PE warm-up. Biometrics, Tanner staging, age of peak height velocity (PHV), vertical jump, whole body lean tissue and fat mass (dual-energy X-ray absorptiometry-derived) were measured at baseline and follow-up. Physical activity was determined by questionnaire. RESULTS: There were no differences in any measured variable between control and intervention groups at baseline. Boys had a significantly older age of PHV than girls (p = 0.02). No group differences were detected for 8-month change in height, weight or maturity measures for the combined sample; however, at 8 months, jumpers had accrued greater lean tissue mass than controls (p = 0.002). Sex-specific analysis revealed that intervention group boys had gained more lean tissue mass than controls (p = 0.016) and experienced significant fat loss (p = 0.010) than controls, an effect that was not observed in the girls. CONCLUSION: Regular, short-duration, jumping activity during adolescence increased lean tissue mass and boys additionally lost fat mass. Sex-specific and/or maturation-specific factors may explain the disparity in effect.


Asunto(s)
Adiposidad , Actividad Motora , Contracción Muscular , Músculo Esquelético/fisiología , Servicios de Salud Escolar , Absorciometría de Fotón , Adolescente , Factores de Edad , Índice de Masa Corporal , Femenino , Humanos , Masculino , Fuerza Muscular , Músculo Esquelético/diagnóstico por imagen , Estudios Prospectivos , Queensland , Factores Sexuales , Encuestas y Cuestionarios , Factores de Tiempo
8.
Osteoporos Int ; 19(11): 1567-77, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18414964

RESUMEN

UNLABELLED: A newly developed bone-specific physical activity questionnaire (BPAQ) was compared with other common measures of physical activity for its ability to predict parameters of bone strength in healthy, young adults. The BPAQ predicted indices of bone strength at clinically relevant sites in both men and women, while other measures did not. INTRODUCTION: Only certain types of physical activity (PA) are notably osteogenic. Most methods to quantify levels of PA fail to account for bone relevant loading. Our aim was to examine the ability of several methods of PA assessment and a new bone-specific measure to predict parameters of bone strength in healthy adults. METHODS: We recruited 40 men and women (mean age 24.5). Subjects completed the modifiable activity questionnaire, Bouchard 3-day activity record, a recently published bone loading history questionnaire (BLHQ), and wore a pedometer for 14 days. We also administered our bone-specific physical activity questionnaire (BPAQ). Calcaneal broadband ultrasound attenuation (BUA) (QUS-2, Quidel) and densitometric measures (XR-36, Norland) were examined. Multiple regression and correlation analyses were performed on the data. RESULTS: The current activity component of BPAQ was a significant predictor of variance in femoral neck bone mineral density (BMD), lumbar spine BMD, and whole body BMD (R(2) = 0.36-0.68, p < 0.01) for men, while the past activity component of BPAQ predicted calcaneal BUA (R(2) = 0.48, p = 0.001) for women. CONCLUSIONS: The BPAQ predicted indices of bone strength at skeletal sites at risk of osteoporotic fracture while other PA measurement tools did not.


Asunto(s)
Densidad Ósea/fisiología , Actividad Motora/fisiología , Encuestas y Cuestionarios , Adolescente , Adulto , Antropometría/métodos , Índice de Masa Corporal , Ejercicio Físico/fisiología , Femenino , Cuello Femoral/fisiología , Humanos , Vértebras Lumbares/fisiología , Masculino , Factores de Tiempo , Soporte de Peso/fisiología , Adulto Joven
9.
Osteoporos Int ; 18(10): 1379-87, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17572834

RESUMEN

UNLABELLED: A simple, appealing, physical activity program can be prescribed to reduce the risk of falls in sedentary, postmenopausal, independent-living, Caucasian women. Foot stamping, progressively loaded squats, and in-line dancing positively influence proximal femoral bone mineral density, lower extremity strength, and static and dynamic balance. INTRODUCTION: Foot stamping, squats exercises, and in-line dancing together create a suitable activity program for sedentary, independent-living older women. METHODS: Forty-five postmenopausal women not taking medications for bone health were randomly assigned to one of three groups. All groups attended one line dance class per week. Two groups additionally performed progressively loaded squats five times per week. One group also performed four foot stamps, twice daily, five times per week. Broadband ultrasound attenuation (BUA), proximal femur (PF) and lumbar spine (LS) bone mineral density (BMD), squats number, and balance variables were measured. RESULTS: There were no differences within or between groups in baseline and follow-up BUA, PF or LS BMD; however, a strong stamp compliance effect was apparent for BUA (r = 0.73) and PF BMD (r = 0.79). Number of squats (p < 0.01) and single leg stance time (p < 0.01) increased, while timed up and go time decreased (p < 0.01) for all participants. CONCLUSIONS: Line dancing, particularly in concert with regular squats and foot stamping, is a simple and appealing strategy that may be employed to reduce lower extremity bone loss, and improve lower limb muscle strength and balance, in independent living, otherwise healthy, postmenopausal Caucasian women.


Asunto(s)
Densidad Ósea/fisiología , Terapia por Ejercicio/métodos , Fémur/fisiología , Osteoporosis Posmenopáusica/terapia , Anciano , Baile/fisiología , Femenino , Humanos , Persona de Mediana Edad , Actividad Motora/fisiología , Fuerza Muscular/fisiología , Osteoporosis Posmenopáusica/fisiopatología , Osteoporosis Posmenopáusica/prevención & control , Cooperación del Paciente , Estudios Prospectivos , Población Blanca/etnología
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