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1.
Int J Geriatr Psychiatry ; 30(5): 539-46, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25132003

RESUMO

OBJECTIVE: Colocation of mental health screening, assessment, and treatment in primary care reduces stigma, improves access, and increases coordination of care between mental health and primary care providers. However, little information exists regarding older adults' attitudes about screening for mental health problems in primary care. The objective of this study was to evaluate older primary care patients' acceptance of and satisfaction with screening for depression and anxiety. METHODS: The study was conducted at an urban, academically affiliated primary care practice serving older adults. Study patients (N = 107) were screened for depression/anxiety and underwent a post-screening survey/interview to assess their reactions to the screening experience. RESULTS: Most patients (88.6%) found the length of the screening to be "just right." A majority found the screening questions somewhat or very acceptable (73.4%) and not at all difficult (81.9%). Most participants did not find the questions stressful (84.9%) or intrusive (91.5%); and a majority were not at all embarrassed (93.4%), upset (93.4%), or uncomfortable (88.8%) during the screening process. When asked about frequency of screening, most patients (72.4%) desired screening for depression/anxiety yearly or more. Of the 79 patients who had spoken with their physicians about mental health during the visit, 89.8% reported that it was easy or very easy to talk with their physicians about depression/anxiety. Multivariate results showed that patients with higher anxiety had a lower positive reaction to the screen when controlling for gender, age, and patient-physician communication. CONCLUSIONS: These results demonstrate strong patient support for depression and anxiety screening in primary care.


Assuntos
Transtornos de Ansiedade/diagnóstico , Prestação Integrada de Cuidados de Saúde/normas , Transtorno Depressivo/diagnóstico , Serviços de Saúde para Idosos/organização & administração , Programas de Rastreamento/organização & administração , Serviços de Saúde Mental/organização & administração , Satisfação do Paciente , Atenção Primária à Saúde/organização & administração , Adulto , Idoso , Feminino , Avaliação Geriátrica/métodos , Serviços de Saúde para Idosos/normas , Humanos , Masculino , Programas de Rastreamento/normas
2.
Rev Sci Instrum ; 83(10): 10D913, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23126916

RESUMO

The 350-keV Cockroft-Walton accelerator at Sandia National laboratory's Ion Beam facility is being used to calibrate absolutely a total DT neutron yield diagnostic based on the (63)Cu(n,2n)(62)Cu(ß+) reaction. These investigations have led to first-order uncertainties approaching 5% or better. The experiments employ the associated-particle technique. Deuterons at 175 keV impinge a 2.6 µm thick erbium tritide target producing 14.1 MeV neutrons from the T(d,n)(4)He reaction. The alpha particles emitted are measured at two angles relative to the beam direction and used to infer the neutron flux on a copper sample. The induced (62)Cu activity is then measured and related to the neutron flux. This method is known as the F-factor technique. Description of the associated-particle method, copper sample geometries employed, and the present estimates of the uncertainties to the F-factor obtained are given.

3.
Bone ; 41(2): 290-6, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17544352

RESUMO

Exercise and bisphosphonate therapies increase bone strength by primarily increasing bone formation and reducing resorption, respectively. Based on these different mechanisms of action, it is possible that combined introduction of exercise and bisphosphonate therapies generates greater improvements in bone mass and strength than either intervention alone. The aim of this study was to examine the individual and combined effects of exercise (treadmill running) and bisphosphonate therapy (alendronate [ALN]) on bone mass and strength in ovariectomized (OVX) rats. Seven-month-old virgin female rats were randomly assigned to either a sham-OVX group (n=13) or one of four OVX groups: vehicle-treated cage-control (VEH-CON, n=10); ALN-treated cage-control (ALN-CON, n=13); vehicle-treated plus treadmill running (VEH-RUN, n=13); and ALN-treated plus treadmill running (ALN-RUN, n=13). ALN-treated groups received twice-weekly ALN (0.015 mg/kg), and exercise groups ran on a motorized treadmill at a 5% incline for 60 min/day, 22-24 m/min, 5 days/week. In vivo measurements included dual-energy X-ray absorptiometry (DXA) of whole-body bone mineral content (BMC), and ex vivo measurements included DXA, micro-computed tomography (muCT), and mechanical testing of the femur and L4 vertebrae. After 14 weeks of intervention, exercise and ALN had additive benefits on whole body and proximal femur BMC, cross-sectional area of the L4 vertebrae, and mechanical properties of the mid-shaft femur. In comparison, for total and mid-shaft femur BMC, L4 vertebrae BMC, and mid-shaft femur cortical thickness and area, there were significant exercise and ALN interactions indicating that the two interventions worked in synergy to enhance bone properties. Supporting the contention that ALN and exercise function via distinct mechanisms of action, ALN successfully reduced medullary canal area suggesting it reduced endocortical bone resorption, whereas exercise augmented periosteal perimeter suggesting it stimulated periosteal bone formation. In summary, we found combined treadmill running and ALN to be more beneficial in preventing declines in bone mass and strength following OVX than the introduction of either intervention alone. These data suggest that a comprehensive program of bisphosphonate therapy and weight-bearing exercise may be an effective method for preventing and treating osteoporosis in post-menopausal women.


Assuntos
Alendronato/farmacologia , Conservadores da Densidade Óssea/farmacologia , Densidade Óssea/efeitos dos fármacos , Exercício Físico , Ovariectomia , Animais , Peso Corporal , Força Compressiva , Feminino , Fêmur/anatomia & histologia , Fêmur/efeitos dos fármacos , Humanos , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344 , Corrida , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/efeitos dos fármacos
4.
Phys Rev Lett ; 91(13): 136402, 2003 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-14525324

RESUMO

We report a Raman scattering study of low-temperature, pressure-induced melting of the charge-density-wave (CDW) phase of 1T-TiSe2. Our measurements reveal that the collapse of the CDW state occurs in three stages: (i) For P<5 kbar, the pressure dependence of the CDW amplitude mode energies and intensities are indicative of a "crystalline" CDW regime; (ii) for 525 kbar, the absence of amplitude modes reveals a metallic regime in which the CDW has melted.

5.
J Musculoskelet Neuronal Interact ; 3(4): 352-5; discussion 356, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15758321
6.
Phys Rev Lett ; 89(22): 226401, 2002 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-12485085

RESUMO

We report a Raman scattering study of the pressure-induced collapse of the Mott-like phases of Ca3Ru2O7 (T(N)=56 K) and Ca2RuO4 (T(N)=110 K). The pressure dependence of the phonon and two-magnon excitations in these materials indicate (i) a T approximately 0 pressure-induced collapse of the antiferromagnetic (AF) insulating phase above P(*) approximately 55 kbar in Ca3Ru2O7 and P(*) approximately 5-10 kbar in Ca2RuO4, (ii) a remarkable insensitivity of the exchange interaction to pressure in both systems, and (iii) evidence for persistent AF correlations above the critical pressure of Ca2RuO4, suggestive of phase separation involving AF insulator and ferromagnetic metal phases.

7.
Phys Rev Lett ; 88(12): 127401, 2002 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-11909499

RESUMO

Raman scattering studies as functions of temperature, magnetic field, and Gd substitution are used to investigate the evolution of magnetic polarons and spin-carrier interactions through the metal-insulator transition in Eu(1-x)Gd(x)O. These studies reveal a spin-fluctuation-dominated paramagnetic (PM) regime for T>T*>T(C), and a coexistence regime for T

8.
Calcif Tissue Int ; 69(1): 7-12, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11685427

RESUMO

The response of the human skeleton to high magnitude loading and unloading is poorly understood. Our aim was to evaluate changes in bone mineral density (BMD) in a group of intercollegiate gymnasts (n = 8, age = 18.6+/-0.8 years) over 24 months that included two 8-month competitive seasons and two 4-month offseasons. BMD of the hip, spine, and whole body was evaluated by DXA (Hologic QDR-1000/W) at baseline, 8, 12, 20, and 24 months. Results indicated significant seasonal trends in BMD of the femoral neck, trochanter, total hip, lumbar spine, and whole body. Specifically, there was a strikingly consistent pattern of bone density increases over the training seasons followed by clear declines in the offseasons. Increases at the spine were 3.5% and 3.7% followed by declines of 1.5% and 1.3% in the offseasons. Total hip BMD increased 2.3% and 1.9% during the competitive seasons followed by decreases of 1.5% and 1.2% in the offseasons. We observed a significant 24-month increase of 4.3% in spine BMD but no significant overall change at the hip. In conclusion, the human skeleton demonstrated a measurable response to high magnitude loading and unloading that was consistent across bone sites over 24 months of observation.


Assuntos
Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Osso e Ossos/metabolismo , Exercício Físico/fisiologia , Ginástica/fisiologia , Estações do Ano , Absorciometria de Fóton , Adolescente , Peso Corporal/fisiologia , Feminino , Humanos , Ciclo Menstrual , Suporte de Carga/fisiologia
9.
Dev Psychol ; 37(2): 265-79, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11269394

RESUMO

A corpus of nearly 150,000 maternal word-tokens used by 53 low-income mothers in 263 mother-child conversations in 5 settings (e.g., play, mealtime, and book readings) was studied. Ninety-nine percent of maternal lexical input consisted of the 3,000 most frequent words. Children's vocabulary performance in kindergarten and later in 2nd grade related more to the occurrence of sophisticated lexical items than to quantity of lexical input overall. Density of sophisticated words heard and the density with which such words were embedded in helpful or instructive interactions, at age 5 at home, independently predicted over a third of the variance in children's vocabulary performance in both kindergarten and 2nd grade. These two variables, with controls for maternal education, child nonverbal IQ, and amount of child's talk produced during the interactive settings, at age 5, predicted 50% of the variance in children's 2nd-grade vocabulary.


Assuntos
Desenvolvimento da Linguagem , Relações Mãe-Filho , Vocabulário , Adulto , Pré-Escolar , Feminino , Seguimentos , Previsões , Humanos , Masculino , Pobreza
10.
J Bone Miner Res ; 16(1): 148-56, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11149479

RESUMO

Physical activity during childhood is advocated as one strategy for enhancing peak bone mass (bone mineral content [BMC]) as a means to reduce osteoporosis-related fractures. Thus, we investigated the effects of high-intensity jumping on hip and lumbar spine bone mass in children. Eighty-nine prepubescent children between the ages of 5.9 and 9.8 years were randomized into a jumping (n = 25 boys and n = 20 girls) or control group (n = 26 boys and n = 18 girls). Both groups participated in the 7-month exercise intervention during the school day three times per week. The jumping group performed 100, two-footed jumps off 61-cm boxes each session, while the control group performed nonimpact stretching exercises. BMC (g), bone area (BA; cm2), and bone mineral density (BMD; g/cm2) of the left proximal femoral neck and lumbar spine (L1-L4) were assessed by dual-energy X-ray absorptiometry (DXA; Hologic QDR/4500-A). Peak ground reaction forces were calculated across 100, two-footed jumps from a 61-cm box. In addition, anthropometric characteristics (height, weight, and body fat), physical activity, and dietary calcium intake were assessed. At baseline there were no differences between groups for anthropometric characteristics, dietary calcium intake, or bone variables. After 7 months, jumpers and controls had similar increases in height, weight, and body fat. Using repeated measures analysis of covariance (ANCOVA; covariates, initial age and bone values, and changes in height and weight) for BMC, the primary outcome variable, jumpers had significantly greater 7-month changes at the femoral neck and lumbar spine than controls (4.5% and 3.1%, respectively). In repeated measures ANCOVA of secondary outcomes (BMD and BA), BMD at the lumbar spine was significantly greater in jumpers than in controls (2.0%) and approached statistical significance at the femoral neck (1.4%; p = 0.085). For BA, jumpers had significantly greater increases at the femoral neck area than controls (2.9%) but were not different at the spine. Our data indicate that jumping at ground reaction forces of eight times body weight is a safe, effective, and simple method of improving bone mass at the hip and spine in children. This program could be easily incorporated into physical education classes.


Assuntos
Densidade Óssea/fisiologia , Exercício Físico/fisiologia , Articulação do Quadril/fisiologia , Vértebras Lombares/fisiologia , Antropometria , Densidade Óssea/efeitos dos fármacos , Cálcio/administração & dosagem , Cálcio/farmacologia , Criança , Pré-Escolar , Feminino , Colo do Fêmur/efeitos dos fármacos , Colo do Fêmur/fisiologia , Articulação do Quadril/efeitos dos fármacos , Humanos , Vértebras Lombares/efeitos dos fármacos , Masculino , Aptidão Física/fisiologia , Caracteres Sexuais
11.
J Bone Miner Res ; 15(12): 2495-503, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11127215

RESUMO

We studied the effects of a 6-month withdrawal of exercise after 12 months of progressive impact (jump) plus lower body resistance training on risk factors for hip fracture in premenopausal women (age, 30-45 years). Twenty-nine women completed the 12-month training and detraining programs and were compared with 22 matched controls. Bone mineral density (BMD) at the greater trochanter, femoral neck, lumbar spine, and whole body and body composition (% body fat) were measured by dual energy X-ray absorptiometry (DXA; Hologic QDR-1000/W). Knee extensor and hip abductor strength were assessed via isokinetic dynamometry (Kin-Com 500H); maximum leg power was tested using a Wingate Anaerobic Power test; and dynamic postural stability was measured on a stabilimeter (Biodex). All measurements were conducted at baseline, 12 months and 18 months with an additional midtraining measurement of BMD. Exercisers trained three times per week in a program of 100 jumps and 100 repetitions of resistance exercises at each session. Intensity was increased using weighted vests to final values of 10% and 13% of body weight (BW) for jump and resistance exercises, respectively. Differences between groups from training were analyzed by repeated measures analysis of covariance (ANCOVA), adjusted for baseline values. Detraining effects were analyzed by comparing the changes from training with the changes from detraining using repeated measures analysis of variance (ANOVA). Baseline values were not significantly different between exercisers and controls. Percent change over the training period was significantly greater in the exercise group than in the control group at the greater trochanter (2.7 +/- 2.5% vs. 0.8 +/- 0.8%, respectively; p < 0.01) and approached significance at the femoral neck (1.2 +/- 3.2% vs. -0.3 +/- 1.9%, respectively; p = 0.06). Significant improvements also were observed in exercisers versus controls for strength and power with exercisers increasing 13-15% above controls, whereas stability was not different between groups. After 6 months of detraining, BMD and muscle strength and power decreased significantly toward baseline values, whereas control values did not change. We conclude that the positive benefits of impact plus resistance training on the musculoskeletal system in premenopausal women reverse when training is withdrawn. Therefore, continued training, perhaps at a reduced frequency and intensity, is required to maintain the musculoskeletal benefit from exercise that may lower fracture risk in later life.


Assuntos
Densidade Óssea , Exercício Físico , Osteoporose Pós-Menopausa/prevenção & controle , Pré-Menopausa , Adulto , Composição Corporal , Feminino , Humanos , Pessoa de Meia-Idade , Contração Muscular , Resistência à Tração
12.
Med Sci Sports Exerc ; 32(11): 1902-7, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11079520

RESUMO

INTRODUCTION: We examined the relationships between insulin-like growth factor I (IGF-I), its binding protein (IGFBP-3), body composition, and bone mineral density (BMD) in collegiate runners (N = 13), gymnasts (N = 10), and noncompetitive women (N = 10). METHODS: Subjects were evaluated by dual-energy x-ray absorptiometry for body composition and BMD of the spine, hip, and whole body, fasting serum levels of IGF-I and IGFBP-3, and dietary intake. The ratio IGF-I/IGFBP-3 was calculated as a marker of IGF-I bioavailability. RESULTS: In ANOVA, IGF-I and IGF-I/IGFBP-3 in athletes with oligomenorrhea and amenorrhea did not differ from eumenorrheic athletes; thus, values were pooled. Lean/height2 and bone mass at the hip and spine were higher in gymnasts than runners and controls. Total caloric intake was similar between groups. IGF-I and IGF-I/IGFBP-3 differed between groups with gymnasts having higher IGF-I values than runners (397+/-58 vs 288+/-73 ng x mL(-1), P < 0.001) and higher IGF-I/IGFBP-3 than controls and runners (0.065+/-0.009 vs 0.056+/-0.008 vs 0.045+/-0.009, P = 0.0001). In simple regression, IGF-I and IGF-/IGFBP-3 were related to lean/height2 and BMD of the lumbar spine and hip (P < 0.01-0.0001). IGF-I and IGF-I/IGFBP-3 were multicollinear; thus, the ratio was used in subsequent stepwise regression. Lean mass, corrected for body surface area (height2), independently predicted spine and trochanteric BMD (R2 = 0.26, 0.28, respectively), whereas IGF-I/IGFBP-3 and lean/height2 together contributed to 48% of the variance in femoral neck BMD. CONCLUSION: We conclude that, in this group of young adult women, lower BMD in runners may be due, in part, to lower levels of IGF-I and the ratio of IGF-I-to-IGFBP-3 and that IGF-I may mediate the relationship between bone and lean mass.


Assuntos
Composição Corporal , Densidade Óssea , Ginástica/fisiologia , Fator de Crescimento Insulin-Like I/análise , Corrida/fisiologia , Adolescente , Adulto , Feminino , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Estado Nutricional
13.
J Womens Health Gend Based Med ; 9(8): 865-72, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11074952

RESUMO

Low bone mineral density (BMD) and poor stability both contribute to increased risk of fractures associated with a fall. Our aim in this cross-sectional study was to determine the anthropometric and/or performance variables that best predicted BMD and stability in women. BMD, body composition, muscle strength, muscle power, and dynamic stability were evaluated in 61 women (age 40 +/- 4 years; % body fat 27% +/- 5%). In correlation analyses, BMD at all sites was significantly related to height, lean mass, strength, and leg power (r2 = 0.25-0.49). Significant inverse relationships were found between all independent variables and dynamic stability (r2 = 0.23-0.52). In stepwise regression, lean mass independently predicted BMD at the femoral neck (R2 = 0.20), total hip (R2 = 0.24), and whole body (R2 = 0.17), whereas hip abductor torque predicted 23% of the variance in trochanter BMD and added 6% to the variance in total hip BMD. Leg power was the only predictor of spine BMD (R2 = 0.14). Fat and lean mass both independently predicted poor performance on postural stability, with fat mass contributing 31% of the total variance (R2 = 0.38). In conclusion, we found lean mass to be a robust predictor of BMD in premenopausal women. Furthermore, both hip abductor torque and leg power independently predicted BMD at clinically relevant fracture sites (hip and spine). The finding that higher fat mass contributes to the majority of the variance in poor stability indicates that greater fat mass may compromise stability and, thus, increase fall risk in heavier individuals.


Assuntos
Composição Corporal , Densidade Óssea/fisiologia , Equilíbrio Postural/fisiologia , Pré-Menopausa , Absorciometria de Fóton , Adulto , Antropometria , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Valor Preditivo dos Testes , Análise de Regressão
14.
J Gerontol A Biol Sci Med Sci ; 55(11): M672-6, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11078097

RESUMO

BACKGROUND: Given that 90% of hip fractures result from a fall, individuals who fall frequently are more likely to be at greater risk for fracture than one-time fallers. Our aim was to determine whether performance variables associated with injurious falls could be used to distinguish frequent fallers from both one-time fallers and nonfallers. METHODS: A total of 157 men and women (77.4-5.4 years) were recruited and categorized into one of the following three groups based on falls status over the previous 12 months: nonfallers (n = 48), one-time fallers (n = 56), and frequent fallers (more than one fall) (n = 53). All subjects were evaluated on functional mobility and lower extremity strength and power. RESULTS: Using multivariate analysis of covariance with height as a covariate, nonfallers were significantly faster than both one-time and frequent fallers during the Get Up and Go (a test involving lower extremity strength and power, and mobility) and faster than one-time fallers on the Tandem Gait (p < .01). There were no significant differences between groups for other mobility variables or for laboratory measures of strength and power. Because one-time and frequent fallers were similar on all measures. they were grouped as "fallers" in discriminant analysis. The Get Up and Go discriminated between the fallers and nonfallers with a final Wilks's Lambda of .900 (p < .001) and correctly classified 72.4% of fallers and nonfallers before crossvalidation and 71.2% of the cases after validation. CONCLUSIONS: Given that the Get Up and Go discriminates between fallers and nonfallers and is associated with lower extremity strength and power, fall prevention strategies should focus on improving both functional mobility and lower extremity strength and power.


Assuntos
Acidentes por Quedas , Idoso , Idoso de 80 Anos ou mais , Feminino , Marcha , Humanos , Perna (Membro)/fisiologia , Masculino
15.
J Gerontol A Biol Sci Med Sci ; 55(9): M489-91, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10995045

RESUMO

BACKGROUND: Bone mineral density (BMD) is a primary risk factor for hip fracture. We studied the effect of long-term weighted vest plus jumping exercise on hip BMD in postmenopausal women as a strategy for reducing hip fracture risk. METHODS: Eighteen postmenopausal women (age = 64.1 +/- 1.6 years at baseline, 69.9 +/- 1.6 years at post-testing) who had participated in a 9-month exercise intervention volunteered for the long-term trial. Nine of the original group engaged in weighted vest plus jumping exercise three times per week for 32 weeks of the year over a period of 5 years. Nine of the original controls were active but not enrolled in the exercise program. BMD of the proximal femur was assessed by dual energy x-ray absorptiometry at baseline and after 5 years. RESULTS: At baseline, groups were similar for age, weight, height, years past menopause, and BMD of the femoral neck, trochanter, and total hip. At follow-up, differences in BMD at all regions of the hip were higher in exercisers than controls. For exercisers, changes in BMD were + 1.54% +/- 2.37%, -0.24% +/- 1.02%, and -0.82% +/- 1.04% (means + SE) at the femoral neck, trochanter, and total hip, respectively; controls decreased at all sites (-4.43% +/- 0.93%. 3.43% +/- 1.09%, and -3.80% +/- 1.03%, respectively). CONCLUSIONS: A 5-year program of weighted vest plus jumping exercise maintains hip BMD by preventing significant bone loss in older postmenopausal women. Furthermore, this particular program appears to promote long-term adherence and compliance, as evidenced by the commitment of the exercisers for more than 5 years.


Assuntos
Terapia por Exercício , Articulação do Quadril/fisiopatologia , Artropatias/prevenção & controle , Osteoporose Pós-Menopausa/prevenção & controle , Levantamento de Peso/fisiologia , Absorciometria de Fóton , Fatores Etários , Idoso , Análise de Variância , Peso Corporal , Densidade Óssea , Feminino , Fêmur/fisiologia , Colo do Fêmur/fisiopatologia , Seguimentos , Fraturas do Quadril/etiologia , Fraturas do Quadril/prevenção & controle , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Cooperação do Paciente , Pós-Menopausa/fisiologia , Fatores de Risco , Suporte de Carga/fisiologia
16.
Med Sci Sports Exerc ; 32(6): 1051-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10862529

RESUMO

PURPOSE: The purpose of this study was to investigate the effects of 9 months of plyometric jump training on bone mineral content (BMC), lower extremity performance, and static balance in adolescent girls (aged 14.6 +/- 0.5 yr; 22.7 +/- 14.0 months past menarche). METHODS: Exercisers (N = 25) trained 30-45 min, three times per week, performing various exercises using weighted vests (squats, lunges, calf raises) and plyometrics (hopping, jumping, bounding, and box depth jumps). The program was designed to load the lower extremities. Controls (N = 28), matched to exercisers for age and months past menarche, maintained their usual activities. The following were assessed at baseline and 9 months: BMC, strength by isokinetic dynamometry, power (Wingate), and static balance. RESULTS: Repeated measures ANOVA revealed no significant differences between groups for BMC, nor were the changes in anthropometric or performance variables, analyzed by MANOVA, significant. In follow-up analyses, t-tests for independent samples revealed that both groups experienced a significant (P < 0.01) increase in percent change in bone mass compared to zero, for the whole body (mean: 3.7% exercisers, 3.6% controls), femoral neck (4.5% vs 2.4%), lumbar spine (L2-4) (6.6% vs 5.3%), and femoral shaft (3.4% vs 2.3%), but only the exercisers improved BMC of the greater trochanter (3.1% vs 1.9%). Furthermore, the exercise group significantly improved knee extensor strength (14.7% vs 7.3%) and medial/lateral balance (38.1% vs 9.5%), whereas the control group demonstrated no changes. The variety of lateral movement activities performed by the exercise group may have contributed to the differences observed between groups for greater trochanter bone mineral density (BMD), leg strength, and medial/lateral balance. CONCLUSION: The trends observed in bone mass between groups suggest that plyometric jump training continued over a longer period of time during adolescent growth may increase peak bone mass.


Assuntos
Densidade Óssea , Osso e Ossos/anatomia & histologia , Terapia por Exercício , Adolescente , Feminino , Humanos , Menarca , Aptidão Física
17.
Mil Med ; 165(5): 379-84, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10826386

RESUMO

A significant number of casualties in previous conflicts died from peripheral vascular wounds. A well-designed tourniquet could possibly have prevented these deaths. The objective of this study was the identification of such a tourniquet. A survey of Special Operations corpsmen established important characteristics necessary in an ideal tourniquet. Because most available devices do not and patented ideas could not meet these criteria, a number of prototypes were developed. Seven potentially satisfactory tourniquets were evaluated by 15 Navy SEAL corpsmen. The success and timing of placement were recorded, and a follow-up questionnaire was completed. Of the several successful tourniquets, two were preferred. Tourniquets incorporating a windlass technique take longer to place and often fail when placed with only one hand. New, relatively simple tourniquet devices incorporating bladder and ratchet mechanisms can significantly improve tourniquet performance.


Assuntos
Medicina Militar/instrumentação , Militares , Medicina Naval/instrumentação , Torniquetes/normas , Guerra , Ferimentos e Lesões/terapia , Atitude do Pessoal de Saúde , Auxiliares de Emergência/psicologia , Desenho de Equipamento , Estudos de Avaliação como Assunto , Humanos , Teste de Materiais , Avaliação das Necessidades , Inquéritos e Questionários , Estados Unidos
18.
Calcif Tissue Int ; 66(6): 399-404, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10821873

RESUMO

There is evidence that high intensity resistance training promotes bone maintenance in older women, however, the effect of high intensity free weight training has not been investigated in older men or women. Furthermore, little is known about the chronic effect of weight training on serum insulin growth factor-I (IGF-I) in this population. We compared the effects of a moderate intensity seated resistance-training program with a high intensity standing free weight exercise program on bone mass and serum levels of IGF-I and IGFBP3 in healthy older men and women. Twenty-eight men (54.6 +/- 3. 2 years) and 26 nonestrogen-replaced women (52.8 +/- 3.3 years) served as their own controls for 12 weeks, then were randomly assigned to a moderate or high intensity training group and trained three times/week for 24 weeks. Prior to and after the control period and at the end of training, bone mass and body composition were assessed by dual energy X-ray absorptiometry (DXA), muscle strength by isokinetic dynamometry, muscular power by Wingate Anaerobic Power Test, and IGF-I by radioimmunoassay (RIA). A repeated measures analysis of covariance (ANCOVA) revealed that high intensity training resulted in a gain in spine BMD in men (1.9%), P < 0.05, but not in women, whereas moderate intensity training produced no changes in either gender at this site. Increases were observed at the greater trochanter, P < 0.03, in men regardless of training intensity, but not in women at any hip site. However, when compared with zero, both men and women in the high intensity group demonstrated significant increases in trochanteric BMD (1.3% and 2. 0%, respectively) and a decrease in femoral BMD (-1.8%). Neither circulating serum IGF-I nor IGFBP3 were altered by either training regimen, but both training programs resulted in improvements in total body strength (37.62%) and lean mass (males 4.1%, females 3. 1%). We conclude that although resistance training of moderate to high intensity produced similar muscle changes in older adults, a higher magnitude is necessary to stimulate osteogenesis at the spine. However, at the spine, intensity was not sufficient to offset low levels of estrogen in early postmenopausal women. Furthermore, bone changes were not accompanied by changes in circulating serum levels of IGF-I or IGFBP3.


Assuntos
Densidade Óssea/fisiologia , Exercício Físico/fisiologia , Aptidão Física/fisiologia , Absorciometria de Fóton , Fatores Etários , Análise de Variância , Índice de Massa Corporal , Feminino , Fêmur/diagnóstico por imagem , Colo do Fêmur/diagnóstico por imagem , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Fatores Sexuais , Levantamento de Peso
19.
J Women Aging ; 12(3-4): 59-75, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11151355

RESUMO

We sought to determine the performance and anthropometric correlates of physical self-concept and self-esteem and to observe whether long-term resistance training would alter these variables in postmenopausal women. Forty-four nonsmoking, community-dwelling, Caucasian women aged 50-75 years participated in the study. Half of the subjects participated in a 9-month regimen of weight-bearing exercises performed 3 times per week which emphasized lower body muscle strength and power development. At baseline, total body fat was negatively associated with physical self-concept and perception of physical appearance but not with self-esteem. Perception of physical appearance improved in both exercisers and controls after the 9-month trial but was most noticeable in exercisers who had low self-esteem at baseline. The only predictor of improvement in perception of physical appearance was a decrease in lower body fat mass. Minimal or nonsignificant change in psychological measures associated with the training may be due to high initial values.


Assuntos
Envelhecimento/psicologia , Composição Corporal , Imagem Corporal , Exercício Físico , Autoimagem , Idoso , Estudos de Casos e Controles , Exercício Físico/psicologia , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa/psicologia , Saúde da Mulher
20.
Med Sci Sports Exerc ; 31(11): 1558-63, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10589857

RESUMO

PURPOSE: We evaluated anthropometric and performance measures that best predict bone mineral density (BMD) and bone mineral content (BMC) in 54 adolescent girls (14.6 +/- 0.5 yr; 22.7 +/- 14.0 months past menarche). METHODS: Whole body, femoral neck, greater trochanter, lumbar spine (L2-L4), and mid-femoral shaft BMD and BMC, and whole body bone-free lean mass and fat mass were assessed using DXA (Hologic QDR 1000/W). Knee extensor strength and leg power were assessed by isokinetic dynamometry and the Wingate Anaerobic Power Test, respectively. RESULTS: Whole body lean mass was correlated with BMD at all bone sites (r = 0.45-0.77; P < 0.001) and was more highly correlated with bone at all sites than was body weight. Leg power was also associated with BMD at all sites (r = 0.41-0.67; P < 0.001), whereas leg strength correlated significantly with all sites (r = 0.41-0.53; P < 0.001) except the lumbar spine. Stepwise regression analyses revealed that 59% of the variance in whole body BMD was predicted by lean mass alone. No other variables, including fat mass, height, months past menarche, leg power, or leg strength, contributed additionally to the regression model. Similarly, lean mass was the only predictor of lumbar spine and femoral shaft BMD (R2 = 0.25, R2 = 0.37, respectively), while femoral neck and trochanteric BMD were best predicted by leg power (R2 = 0.38, R2 = 0.36, respectively). Similar but stronger models emerged using BMC as the outcome, with lean mass and leg power explaining the most variance in BMC values. CONCLUSION: In this group of adolescent girls, lean body mass and leg power best predicted BMC and BMD of the whole body, lumbar spine, femoral shaft, and hip, which may suggest an important role for muscle mass development during growth to maximize peak bone density.


Assuntos
Índice de Massa Corporal , Densidade Óssea , Perna (Membro)/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Absorciometria de Fóton , Tecido Adiposo/anatomia & histologia , Adolescente , Limiar Anaeróbio/fisiologia , Antropometria , Composição Corporal/fisiologia , Estatura/fisiologia , Peso Corporal/fisiologia , Estudos Transversais , Feminino , Fêmur/anatomia & histologia , Colo do Fêmur/anatomia & histologia , Previsões , Humanos , Articulação do Joelho/fisiologia , Vértebras Lombares/anatomia & histologia , Menarca , Modelos Biológicos , Músculo Esquelético/fisiologia , Análise de Regressão , Fatores de Tempo
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