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1.
Med Sci Sports Exerc ; 55(10): 1750-1760, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37144634

RESUMO

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.


Assuntos
Densidade Óssea , Osteoporose Pós-Menopausa , Feminino , Humanos , Pessoa de Meia-Idade , Creatina , Pós-Menopausa , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/tratamento farmacológico , Colo do Fêmur , Suplementos Nutricionais , Método Duplo-Cego
2.
Med Sci Sports Exerc ; 53(11): 2388-2395, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34107512

RESUMO

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.


Assuntos
Densidade Óssea/fisiologia , Creatina/administração & dosagem , Suplementos Nutricionais , Força Muscular/fisiologia , Treinamento Resistido , Acidentes por Quedas/prevenção & controle , Fatores Etários , Idoso , Remodelação Óssea/fisiologia , Osso e Ossos/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Tomografia Computadorizada por Raios X
3.
Nutr Health ; 27(2): 151-159, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33234019

RESUMO

BACKGROUND: The combination of creatine supplementation and resistance training (10-12 weeks) has been shown to increase bone mineral content and reduce a urinary indicator of bone resorption in older males compared with placebo. However, the longer-term effects (12 months) of creatine and resistance training on bone mineral density and bone geometric properties in older males is unknown. AIM: To assess the effects of 12 months of creatine supplementation and supervised, whole-body resistance training on bone mineral density, bone geometric properties, muscle accretion, and strength in older males. METHODS: Participants were randomized to supplement with creatine (n = 18, 49-69 years, 0.1 g·kg-1·d-1) or placebo (n = 20, 49-67 years, 0.1 g·kg-1·d-1) during 12 months of supervised, whole-body resistance training. RESULTS: After 12 months of training, both groups experienced similar changes in bone mineral density and geometry, bone speed of sound, lean tissue and fat mass, muscle thickness, and muscle strength. There was a trend (p = 0.061) for creatine to increase the section modulus of the narrow part of the femoral neck, an indicator of bone bending strength, compared with placebo. Adverse events did not differ between creatine and placebo. CONCLUSIONS: Twelve months of creatine supplementation and supervised, whole-body resistance training had no greater effect on measures of bone, muscle, or strength in older males compared with placebo.


Assuntos
Creatina , Treinamento Resistido , Idoso , Composição Corporal , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Masculino , Força Muscular , Músculo Esquelético , Músculos
4.
Med Sci Sports Exerc ; 49(4): 633-640, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27875501

RESUMO

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.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Ibuprofeno/uso terapêutico , Músculo Esquelético/efeitos dos fármacos , Pós-Menopausa , Treinamento Resistido , Absorciometria de Fóton , Idoso , Dieta , Feminino , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/efeitos dos fármacos , Pessoa de Meia-Idade , Força Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/diagnóstico por imagem , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/efeitos dos fármacos , Tomografia Computadorizada por Raios X
5.
Bone Rep ; 5: 96-103, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28326351

RESUMO

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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