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1.
Med Sci Sports Exerc ; 55(10): 1750-1760, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37144634

RESUMEN

PURPOSE: Our purpose was to examine the effects of 2 yr of creatine monohydrate supplementation and exercise on bone health in postmenopausal women. METHODS: Two hundred and thirty-seven postmenopausal women (mean age, 59 yr) were randomized to receive creatine (0.14 g·kg -1 ·d -1 ) or placebo during a resistance training (3 d·wk -1 ) and walking (6 d·wk -1 ) program for 2 yr. Our primary outcome was the femoral neck bone mineral density (BMD), with lumbar spine BMD and proximal femur geometric properties as the secondary outcomes. RESULTS: Compared with placebo, creatine supplementation had no effect on BMD of the femoral neck (creatine: 0.725 ± 0.110 to 0.712 ± 0.100 g·cm -2 ; placebo: 0.721 ± 0.102 to 0.706 ± 0.097 g·cm -2 ), total hip (creatine: 0.879 ± 0.118 to 0.872 ± 0.114 g·cm -2 ; placebo: 0.881 ± 0.111 to 0.873 ± 0.109 g·cm -2 ), or lumbar spine (creatine: 0.932 ± 0.133 to 0.925 ± 0.131 g·cm -2 ; placebo: 0.923 ± 0.145 to 0.915 ± 0.143 g·cm -2 ). Creatine significantly maintained section modulus (1.35 ± 0.29 to 1.34 ± 0.26 vs 1.34 ± 0.25 to 1.28 ± 0.23 cm 3 (placebo), P = 0.0011), predictive of bone bending strength, and buckling ratio (10.8 ± 2.6 to 11.1 ± 2.2 vs 11.0 ± 2.6 to 11.6 ± 2.7 (placebo), P = 0.011), predictive of reduced cortical bending under compressive loads, at the narrow part of the femoral neck. Creatine reduced walking time over 80 m (48.6 ± 5.6 to 47.1 ± 5.4 vs 48.3 ± 4.5 to 48.2 ± 4.9 s (placebo), P = 0.0008) but had no effect on muscular strength (i.e., one-repetition maximum) during bench press (32.1 ± 12.7 to 42.6 ± 14.1 vs 30.6 ± 10.9 to 41.4 ± 14 kg (placebo)) and hack squat (57.6 ± 21.6 to 84.4 ± 28.1 vs 56.6 ± 24.0 to 82.7 ± 25.0 kg (placebo)). In the subanalysis of valid completers, creatine increased lean tissue mass compared with placebo (40.8 ± 5.7 to 43.1 ± 5.9 vs 40.4 ± 5.3 to 42.0 ± 5.2 kg (placebo), P = 0.046). CONCLUSIONS: Two years of creatine supplementation and exercise in postmenopausal women had no effect on BMD; yet, it improved some bone geometric properties at the proximal femur.


Asunto(s)
Densidad Ósea , Osteoporosis Posmenopáusica , Femenino , Humanos , Persona de Mediana Edad , Creatina , Posmenopausia , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/tratamiento farmacológico , Cuello Femoral , Suplementos Dietéticos , Método Doble Ciego
2.
Int J Exerc Sci ; 15(2): 1117-1132, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35992184

RESUMEN

The purpose was to investigate the effects of progressive resistance training (PRT) and creatine supplementation in stroke survivors. Participants were randomized to one of two groups: creatine (n = 5; 51 ± 16y) or placebo (n = 3; 73 ± 8y) during 10 weeks of supervised PRT. Prior to and following PRT and supplementation, assessments were made for body composition (lean tissue and fat mass), muscle thickness, muscle strength (1-repetition maximum), functional exercise capacity (6-minute walk test, Berg Balance Scale; BBS), cognition (Montreal Cognitive Assessment; MoCA), and symptoms of anxiety (Generalized Anxiety Disorder Assessment-7; GAD-7) and depression (Center for Epidemiological Studies Depression Scale; CES-D). There were time main effects for leg press strength (increased; p = 0.001), chest press strength (increased; p = 0.003), elbow flexor muscle thickness (increased; p = 0.007), BBS (increased; p = 0.002), MoCA (increased; p = 0.031) and CES-D (decreased; p = 0.045). There was a group x time interaction for the 6 minute walk test (p = 0.039). The creatine group significantly increased walking distance over time (p = 0.002) with no change in the placebo group (p = 0.120). Ten weeks of PRT had some positive effects on measures of muscle strength and size, balance, cognition and depression. The addition of creatine to PRT significantly improved walking performance in stroke survivors.

3.
Med Sci Sports Exerc ; 53(11): 2388-2395, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34107512

RESUMEN

PURPOSE: To examine the efficacy of creatine (Cr) supplementation and any sex differences during supervised whole-body resistance training (RT) on properties of bone and muscle in older adults. METHODS: Seventy participants (39 men, 31 women; mean age ± standard deviation: 58 ± 6 yr) were randomized to supplement with Cr (0.1 g·kg-1·d-1) or placebo (Pl) during RT (3 d·wk-1 for 1 yr). Bone geometry (radius and tibia) and muscle area and density (forearm and lower leg) were assessed using peripheral quantitative computed tomography. RESULTS: Compared with Pl, Cr increased or maintained total bone area in the distal tibia (Cr, Δ +17 ± 27 mm2; Pl, Δ -1 ± 22 mm2; P = 0.031) and tibial shaft (Cr, Δ 0 ± 9 mm2; Pl, Δ -5 ± 7 mm2; P = 0.032). Men on Cr increased trabecular (Δ +28 ± 31 mm2; P < 0.001) and cortical bone areas in the tibia (Δ +4 ± 4 mm2; P < 0.05), whereas men on Pl increased trabecular bone density (Δ +2 ± 2 mg·cm-3; P < 0.01). There were no bone changes in the radius (P > 0.05). Cr increased lower leg muscle density (Δ +0.83 ± 1.15 mg·cm-3; P = 0.016) compared with Pl (Δ -0.16 ± 1.56 mg·cm-3), with no changes in the forearm muscle. CONCLUSIONS: One year of Cr supplementation and RT had some favorable effects on measures of bone area and muscle density in older adults.


Asunto(s)
Densidad Ósea/fisiología , Creatina/administración & dosificación , Suplementos Dietéticos , Fuerza Muscular/fisiología , Entrenamiento de Fuerza , Accidentes por Caídas/prevención & control , Factores de Edad , Anciano , Remodelación Ósea/fisiología , Huesos/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/anatomía & histología , Músculo Esquelético/fisiología , Tomografía Computarizada por Rayos X
4.
Bone Rep ; 12: 100248, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32071953

RESUMEN

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, with clinical symptoms including menstrual dysfunction and hyperandrogenemia, as well as insulin resistance which is thought to be a key contributing factor to symptoms. Insulin is also thought to positively affect bone while oligo- and amenorrhea are known to negatively affect bone. Lifestyle modification is the first recommendation to treat symptoms of PCOS; however, little is known about the effect of lifestyle interventions on bone measures in this population. Pulses (e.g., chickpeas, beans, split peas, lentils) have been shown to lower fasting insulin, and the objective of this study was to determine the effect of a pulse-based diet compared to the therapeutic lifestyle changes (TLC) diet on bone measures and body composition in women with PCOS. Women aged 18-35 years with PCOS were randomized to either a pulse-based diet or the TLC diet for 16-weeks while following an aerobic exercise program. Thirty-one in the TLC group and 29 in the pulse group completed dual-energy X-ray absorptiometry analysis following the intervention. After 16-weeks, both groups had a lower BMI, whole body fat mass, and % fat (p < 0.005), with no difference in lean mass. In both groups, lumbar spine bone mineral content (BMC) and density were higher following the intervention (p < 0.05) while femoral neck bone mineral density (BMD) was lower (p < 0.05). Intertrochanteric section modulus improved in both groups while there was a group x time interaction in femoral shaft subperiosteal width which was more favorable in the pulse group (p < 0.05). This study demonstrates that the femoral neck may be compromised during a lifestyle intervention in women with PCOS. Research is warranted to preserve bone health during lifestyle change in women with PCOS.

5.
J Psychosom Obstet Gynaecol ; 41(2): 144-153, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31558086

RESUMEN

Objective: A favorable dietary composition to increase health-related quality of life (HRQoL) in PCOS remains unclear. We compared changes in HRQoL of women with PCOS who participated in a low-glycemic-index pulse-based (lentils, beans, split peas, and chickpeas) or the Therapeutic Lifestyle Changes (TLC) diet intervention.Methods: Thirty women in the pulse-based and 31 in the TLC groups (18-35 years) completed a 16-week intervention without energy-restriction. Groups participated in health counseling (monthly) and aerobic exercise (5 days/week; 45 minutes/day).Results: Fifty-five (90.2%) women completed a PCOS-specific HRQoL survey. Greatest mean increases in time-effects occurred in the domains of healthy eating, PCOS knowledge, active living, healthcare satisfaction, feelings and experiences about intervention, and health concerns, respectively (p ≤ 0.02), without group-by-time interactions (p ≥ 0.13). Decreased weight (r = -0.35) and homeostatic model assessment of insulin resistance (r = -0.18) correlated with increased scores of PCOS knowledge; adherence to intervention correlated with increased scores of active living (r = 0.39) and healthy eating (r = 0.53; p ≤ 0.03).Conclusions: Both interventions improved HRQoL scores in women with PCOS without prescribed energy-restriction. Our observations add novel insights into current evidence and elucidate the need for future psychological research to target lifestyle modifications for improving HRQoL and unique psychological complications of PCOS in this high-risk population (CinicalTrials.gov identifier:NCT01288638).


Asunto(s)
Consejo , Terapia por Ejercicio , Síndrome del Ovario Poliquístico/dietoterapia , Calidad de Vida , Adolescente , Adulto , Índice de Masa Corporal , Dieta , Ejercicio Físico , Femenino , Humanos , Resistencia a la Insulina , Estilo de Vida , Obesidad/complicaciones , Adulto Joven
6.
BMC Endocr Disord ; 19(1): 70, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31262307

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in young women and increases risk of cardiovascular and metabolic disease, and infertility. Women with PCOS share many characteristics commonly associated with aging including chronic inflammation and insulin resistance, which may be associated with "sarcopenic obesity", a term used to describe low appendicular skeletal muscle mass relative to total body mass. The purpose of this work was to determine the prevalence of sarcopenic obesity in women with PCOS. We hypothesized there would be a high prevalence of sarcopenic obesity, and that % appendicular skeletal muscle mass and markers of inflammation and insulin resistance would be inversely correlated in this population. METHODS: Dual energy X-ray absorptiometry was used to assess body composition in 68 women with PCOS aged 18-35y and 60 healthy age-matched women from the same geographic area. Sarcopenic obesity was defined as having % appendicular skeletal muscle mass 2 standard deviations below the mean for the healthy age-matched controls and a % body fat above 35%. Data were analyzed with Mann-Whitney U-tests and Spearman correlations. RESULTS: 53% of women with PCOS were classified as sarcopenic obese. Women with PCOS had a median (interquartile range) appendicular skeletal muscle mass of 23.8 (22.3-25.8)% which was lower than the control median of 30.4 (28.6-32.4)% (p < 0.0001). Among women with PCOS, there were negative correlations between % appendicular skeletal muscle mass and the homeostasis model assessment insulin resistance index (r = - 0.409; p < 0.01), high sensitivity C-reactive protein (r = - 0.608; p < 0.0001) and glycosylated hemoglobin (r = - 0.430; p < 0.0001). Furthermore, % appendicular skeletal muscle mass correlated positively with vitamin D (r = 0.398; p < 0.0001) in women with PCOS, which is thought to positively affect skeletal muscle mass. CONCLUSIONS: Women with PCOS have a high prevalence of sarcopenic obesity, which is correlated to insulin resistance and inflammation.


Asunto(s)
Composición Corporal , Obesidad/complicaciones , Síndrome del Ovario Poliquístico/complicaciones , Sarcopenia/complicaciones , Absorciometría de Fotón , Índice de Masa Corporal , Estudios de Casos y Controles , Femenino , Humanos , Insulina/metabolismo , Resistencia a la Insulina , Obesidad/epidemiología , Factores de Riesgo , Sarcopenia/epidemiología , Vitamina D/sangre
7.
J Obstet Gynaecol Can ; 41(10): 1453-1460, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30712903

RESUMEN

OBJECTIVE: This study compared the prevalence of metabolic syndrome (MetS) and characterized type 2 diabetes (DM2) and cardiovascular disease (CVD) risk profiles between Canadian women with polycystic ovary syndrome (PCOS) and healthy women recruited from the general population. Furthermore, within the PCOS cohort, the study contrasted the CVD and DM2 risk profiles of women with or without MetS. METHODS: Measures of MetS (International Diabetes Federation; National Heart, Lung, and Blood Institute; and the American Heart Association definition), DM2 (Diabetes Canada Clinical Guidelines), and CVD risk factors (Androgen Excess and Polycystic Ovary Syndrome Society statement) were evaluated for 237 women with PCOS (Androgen Excess and PCOS Society definitions) and 42 controls (aged 18-36) in a prospective observational study (Canadian Task Force Classification II-2). RESULTS: The prevalence of MetS was 29.5% in the PCOS group, which was approximately six-fold higher than age-matched controls (P < 0.001). Women with PCOS exhibited higher glucose abnormality, acanthosis nigricans, total cholesterol to high-density lipoprotein cholesterol ratio (TC/HDL-C), and lower sex hormone-binding globulin concentrations when compared with controls after accounting for differences in the BMI (P < 0.01). Further, women with PCOS and MetS exhibited exacerbated insulin and glucose responses to a 75-g oral glucose tolerance test and greater acanthosis nigricans, hirsutism, TC/HDL-C, TC, and sex hormone-binding globulin concentrations compared with their BMI-adjusted counterparts without MetS (P < 0.05). CONCLUSION: Canadian reproductive-age women with PCOS have a high prevalence of MetS and exhibit adverse cardiometabolic risk factors that warrant early screening and regular monitoring across their reproductive lifespan.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Intolerancia a la Glucosa/epidemiología , Síndrome Metabólico/epidemiología , Síndrome del Ovario Poliquístico/epidemiología , Acantosis Nigricans/epidemiología , Acné Vulgar/epidemiología , Adolescente , Adulto , Glucemia/metabolismo , Presión Sanguínea , Índice de Masa Corporal , Canadá/epidemiología , Estudios de Casos y Controles , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol , Femenino , Intolerancia a la Glucosa/metabolismo , Prueba de Tolerancia a la Glucosa , Hirsutismo/epidemiología , Humanos , Resistencia a la Insulina , Síndrome Metabólico/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Prevalencia , Estudios Prospectivos , Medición de Riesgo , Globulina de Unión a Hormona Sexual/metabolismo , Adulto Joven
8.
J Clin Densitom ; 21(1): 54-60, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28034591

RESUMEN

Polycystic ovary syndrome (PCOS) is an endocrine disorder affecting women of reproductive age manifesting with polycystic ovaries, menstrual irregularities, hyperandrogenism, hirsutism, and insulin resistance. The oligomenorrhea and amenorrhea characteristic to PCOS are associated with low bone mineral density (BMD); conversely, the hyperandrogenism and hyperinsulinemia may elicit a protective effect on BMD. As bone geometric properties provide additional information about bone strength, the objective of this study was to compare measures of hip geometry in women with PCOS to a healthy female population. Using dual-energy X-ray absorptiometry, BMD and measures of hip geometry were determined in women with PCOS (n = 60) and healthy controls (n = 60) aged 18-35 years. Clinical biochemical measures were also determined in women with PCOS. Measures of hip geometry, including cross-sectional area, cross-sectional moment of inertia, subperiosteal width (SPW), and section modulus, were similar between groups following correction for body mass index (BMI) (all p > 0.05) with intertrochanter SPW significantly lower in women with PCOS (p < 0.05). BMI-corrected whole body BMD as well as the lumbar spine and regions of proximal femur were also comparable between groups. In women with PCOS, BMI-corrected correlations were found between insulin and femoral shaft SPW (r = 0.322, p < 0.05), glucose and femoral neck (r = 0.301, p < 0.05), and trochanter BMD (0.348, p < 0.05), as well as between testosterone and femoral neck BMD (0.376, p < 0.05) and narrow neck cross-sectional area (0.306, p < 0.05). This study demonstrates that women with PCOS may have compromised intertrochanter SPW while oligomenorrhea appears to have no detrimental effect on bone density or geometry in women with PCOS.


Asunto(s)
Densidad Ósea , Fémur/diagnóstico por imagen , Síndrome del Ovario Poliquístico/diagnóstico por imagen , Síndrome del Ovario Poliquístico/fisiopatología , Absorciometría de Fotón , Adolescente , Adulto , Glucemia/metabolismo , Índice de Masa Corporal , Estudios de Casos y Controles , Diáfisis/diagnóstico por imagen , Diáfisis/fisiopatología , Femenino , Fémur/fisiopatología , Cabeza Femoral/diagnóstico por imagen , Cabeza Femoral/fisiopatología , Cuello Femoral/diagnóstico por imagen , Cuello Femoral/fisiopatología , Humanos , Insulina/sangre , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/fisiopatología , Testosterona/sangre , Adulto Joven
9.
Med Sci Sports Exerc ; 49(4): 633-640, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27875501

RESUMEN

INTRODUCTION/PURPOSE: Resistance training with ibuprofen supplementation may improve musculoskeletal health in postmenopausal women. The study purpose was to determine the efficacy of resistance training and ibuprofen supplementation on bone and muscle properties in postmenopausal women. METHODS: Participants (n = 90, 65.3 ± 4.9 yr) were randomly assigned to: supervised resistance training or stretching (placebo-exercise) with postexercise ibuprofen (400 mg) or placebo supplementation for 3 d·wk (9 months). Baseline and postintervention measurements included distal and shaft scans of the forearm and lower leg using peripheral quantitative computed tomography. Distal site outcomes included cross-sectional area, content, and density for total and trabecular bone, as well as estimated bone strength in compression. Shaft site outcomes included total bone area; cortical bone area, content, and density; estimated bone strength in torsion; and muscle area and density. RESULTS: Exercise-supplement-time interactions for total bone content at the distal radius (P = 0.009) and cortical density at the radius shaft (P = 0.038) were significant. Resistance training with ibuprofen decreased total bone content (-1.5%) at the distal radius in comparison to the resistance training (0.6%; P = 0.032) and ibuprofen alone (0.5%; P = 0.050). Change in cortical density at the radius shaft differed between the stretching with placebo and ibuprofen supplementation groups (-1.8% vs 1.1%; P = 0.050). Resistance training preserved muscle density in the lower leg more so than stretching (-3.1% vs -5.4%; P = 0.015). CONCLUSIONS: Ibuprofen consumed immediately after resistance training had a deleterious effect on bone mineral content at the distal radius, whereas resistance training or ibuprofen supplementation individually prevented bone loss. Resistance training prevented muscle density decline in the lower leg.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Densidad Ósea/efectos de los fármacos , Ibuprofeno/uso terapéutico , Músculo Esquelético/efectos de los fármacos , Posmenopausia , Entrenamiento de Fuerza , Absorciometría de Fotón , Anciano , Dieta , Femenino , Fémur/diagnóstico por imagen , Fémur/efectos de los fármacos , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/efectos de los fármacos , Persona de Mediana Edad , Fuerza Muscular/fisiología , Músculo Esquelético/anatomía & histología , Músculo Esquelético/diagnóstico por imagen , Radio (Anatomía)/diagnóstico por imagen , Radio (Anatomía)/efectos de los fármacos , Tomografía Computarizada por Rayos X
10.
Bone Rep ; 5: 96-103, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28326351

RESUMEN

PURPOSE: To compare the effects of nine months of exercise training and ibuprofen supplementation (given immeditately after exercise sessions) on bone and muscle in postmenopausal women. METHODS: In a double-blind randomized trial, participants (females: n = 90, mean age 64.8, SD 4.3 years) were assigned (computer generated, double blind) to receive supervised resistance training or stretching 3 days/week, and ibuprofen (400 mg, post-exercise) or placebo (i.e. 4 groups) for 9 months. In this proof-of-concept study the sample size was halved from required 200 identified via 90% power calculation. Baseline and post-intervention testing included: Dual energy x-ray absorptiometry (DXA) for lumbar spine, femoral neck, and total body areal bone mineral density (aBMD); geometry of proximal femur; total body lean tissue and fat mass; predicted 1-repetition maximum muscle strength testing (1RM; biceps curl, hack squat). RESULTS: Exercise training or ibuprofen supplementation had no effects on aBMD of the lumbar spine, femoral neck, and total body. There was a significant exercise × supplement × time interaction for aBMD of Ward's region of the femoral neck (p = 0.015) with post hoc comparison showing a 6% decrease for stretching with placebo vs. a 3% increase for stretching with ibuprofen (p = 0.017). Resistance training increased biceps curl and hack squat strength vs. stretching (22% vs. 4% and 114% vs. 12%, respectively) (p < 0.01) and decreased percent body fat compared to stretching (2% vs. 0%) (p < 0.05). CONCLUSIONS: Ibuprofen supplementation provided some benefits to bone when taken independent of exercise training in postmenopausal women. This study provides evidence towards a novel, easily accessible stimulus for enhancing bone health [i.e. ibuprofen].

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