RESUMO
Creatine has become one of the most popular dietary supplements among a wide range of healthy and clinical populations. However, its potential adverse effects on kidney health are still a matter of concern. This is a narrative review of the effects of creatine supplementation on kidney function. Despite a few case reports and animal studies suggesting that creatine may impair kidney function, clinical trials with controlled designs do not support this claim. Creatine supplementation may increase serum creatinine (Crn) concentration for some individuals, but it does not necessarily indicate kidney dysfunction, as creatine is spontaneously converted into Crn. Based on studies assessing kidney function using reliable methods, creatine supplements have been shown to be safe for human consumption. Further studies with people who have pre-existing kidney disease remain necessary.
Assuntos
Creatina , Insuficiência Renal , Animais , Humanos , Creatina/efeitos adversos , Insuficiência Renal/induzido quimicamente , Rim , Taxa de Filtração Glomerular , Suplementos Nutricionais/efeitos adversos , CreatininaRESUMO
BACKGROUND: Stroke is a leading cause of mortality and disability, and its sequelae are associated with inadequate food intake which can lead to sarcopenia. The aim of this study is to verify the effectiveness of creatine supplementation on functional capacity, strength, and changes in muscle mass during hospitalization for stroke compared to usual care. An exploratory subanalysis will be performed to assess the inflammatory profiles of all participants, in addition to a follow-up 90 days after stroke, to verify functional capacity, muscle strength, mortality, and quality of life. METHODS: Randomized, double-blind, unicenter, parallel-group trial including individuals with ischemic stroke in the acute phase. The duration of the trial for the individual subject will be approximately 90 days, and each subject will attend a maximum of three visits. Clinical, biochemical, anthropometric, body composition, muscle strength, functional capacity, degree of dependence, and quality of life assessments will be performed. Thirty participants will be divided into two groups: intervention (patients will intake one sachet containing 10g of creatine twice a day) and control (patients will intake one sachet containing 10g of placebo [maltodextrin] twice a day). Both groups will receive supplementation with powdered milk protein serum isolate to achieve the goal of 1.5g of protein/kg of body weight/day and daily physiotherapy according to the current rehabilitation guidelines for patients with stroke. Supplementation will be offered during the 7-day hospitalization. The primary outcomes will be functional capacity, strength, and changes in muscle mass after the intervention as assessed by the Modified Rankin Scale, Timed Up and Go test, handgrip strength, 30-s chair stand test, muscle ultrasonography, electrical bioimpedance, and identification of muscle degradation markers by D3-methylhistidine. Follow-up will be performed 90 days after stroke to verify functional capacity, muscle strength, mortality, and quality of life. DISCUSSION: The older population has specific nutrient needs, especially for muscle mass and function maintenance. Considering that stroke is a potentially disabling event that can lead the affected individual to present with numerous sequelae, it is crucial to study the mechanisms of muscle mass loss and understand how adequate supplementation can help these patients to better recover. TRIAL REGISTRATION: The Brazilian Clinical Trials Registry (ReBEC) RBR-9q7gg4 . Registered on 21 January 2019.
Assuntos
Creatina , Acidente Vascular Cerebral , Humanos , Creatina/efeitos adversos , Força da Mão , Qualidade de Vida , Equilíbrio Postural , Estudos de Tempo e Movimento , Força Muscular , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/tratamento farmacológico , Suplementos Nutricionais/efeitos adversos , Músculos , Método Duplo-Cego , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Creatine has been considered an effective ergogenic aid for several decades; it can help athletes engaged in a variety of sports and obtain performance gains. Creatine supplementation increases muscle creatine stores; several factors have been identified that may modify the intramuscular increase and subsequent performance benefits, including baseline muscle Cr content, type II muscle fibre content and size, habitual dietary intake of Cr, aging, and exercise. Timing of creatine supplementation in relation to exercise has recently been proposed as an important consideration to optimise muscle loading and performance gains, although current consensus is lacking regarding the ideal ingestion time. Research has shifted towards comparing creatine supplementation strategies pre-, during-, or post-exercise. Emerging evidence suggests greater benefits when creatine is consumed after exercise compared to pre-exercise, although methodological limitations currently preclude solid conclusions. Furthermore, physiological and mechanistic data are lacking, in regard to claims that the timing of creatine supplementation around exercise moderates gains in muscle creatine and exercise performance. This review discusses novel scientific evidence on the timing of creatine intake, the possible mechanisms that may be involved, and whether the timing of creatine supplementation around exercise is truly a real concern.
Assuntos
Creatina/administração & dosagem , Suplementos Nutricionais , Exercício Físico/fisiologia , Músculo Esquelético/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/administração & dosagem , Creatina/efeitos adversos , Creatina/metabolismo , Suplementos Nutricionais/efeitos adversos , Esquema de Medicação , Feminino , Humanos , Masculino , Músculo Esquelético/metabolismo , Substâncias para Melhoria do Desempenho/efeitos adversos , Substâncias para Melhoria do Desempenho/metabolismo , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Creatine represents a natural supplement and ergogenic aid for sport performance, but there are several concerns regarding its safety for health. The present double-blind placebo-controlled study evaluated the effect of creatine monohydrate supplementation on a panel of blood and urine health indicators in resistance training practitioners. METHODS: Eighteen males performing resistance training three times per week were supplemented with 0.3 g/kg per day creatine monohydrate for 7 days and compared with matched controls supplemented with dextrosol. Blood and urine samples were collected pre- and 30 days post-supplementation to evaluate 41 biochemical parameters and renal function. RESULTS: Creatine monohydrate supplementation did not cause adverse events and, as expected, promoted an increase of the performance and body weight. No modification of red blood cells parameters, white blood cells profile, blood lipid profile, metabolic and urine markers, hepatic and renal function were observed in the supplemented group. CONCLUSIONS: Despite the expected weight increase, the creatine monohydrate supplementation is safe for health and no detrimental effects on different organs and physiological systems were observed in our cohort of volunteers.
Assuntos
Desempenho Atlético/fisiologia , Creatina/administração & dosagem , Creatina/efeitos adversos , Suplementos Nutricionais , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/efeitos adversos , Treinamento Resistido , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Método Duplo-Cego , Testes Hematológicos , Humanos , Rim/fisiologia , Contagem de Leucócitos , Lipídeos/sangue , Fígado/fisiologia , Masculino , Músculo Esquelético/metabolismo , Aumento de Peso , Adulto JovemRESUMO
BACKGROUND: Case studies and reviews have shown that creatine supplementation can affect kidney function. The objective of this study is to verify the effects of 8 weeks of creatine supplementation on renal function (creatinine clearance: primary outcome) in patients with symptomatic peripheral arterial disease. METHODS: Twenty-nine patients, of both genders, were randomized (1:1) in a double-blind manner for administration of Placebo (PLA; n = 15) or creatine monohydrate (Cr; n = 14). The supplementation protocol consisted of 20 g/day for 1 week divided into 4 equal doses (loading phase), followed by single daily doses of 5 g in the subsequent 7 weeks (maintenance phase). Before and after the supplementation period, markers of renal function, serum creatinine, creatinine excretion rate, and creatinine clearance were evaluated. The Generalized Estimation Equation Model was used for comparison between groups. The level of significance was P < 0.05. RESULTS: No significant differences were found between groups before and after the intervention for serum creatinine (Cr: pre 1.00 ± 0.15 mL/dL vs. post 1.07 ± 0.16 mL/dL; PLA: pre 1.30 ± 0.53 mL/dL vs. post 1.36 ± 0.47 mL/dL, P = 0.590), creatinine excretion rate (Cr: pre 81.73 ± 43.80 mg/dL vs. post 102.92 ± 59.57 mg/dL; PLA: pre 74.37 ± 38.90 mg/dL vs. post 86.22 ± 39.94 mg/dL, P = 0.560), or creatinine clearance (Cr; pre 108 ± 59 mL/min/1.73 m2 vs. post 117 ± 52 mL/min/1.73 m2; PLA: pre 88 ± 49 mL/min/1.73 m2 vs. post 82 ± 47 mL/min/1.73 m2, P = 0.366). CONCLUSIONS: Eight weeks of creatine supplementation is safe and does not compromise the renal function of patients with peripheral arterial disease.
Assuntos
Creatina/administração & dosagem , Suplementos Nutricionais , Taxa de Filtração Glomerular/efeitos dos fármacos , Rim/efeitos dos fármacos , Doença Arterial Periférica/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Creatina/efeitos adversos , Creatinina/sangue , Creatinina/urina , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/fisiopatologia , Eliminação Renal/efeitos dos fármacos , Fatores de Tempo , Resultado do TratamentoRESUMO
Creatine supplements may transitorily rise serum creatinine levels and mimic a kidney disease. If its use is associated with a high protein diet, the resulting increase in blood urea nitrogen will increase the confusion. Since clinical laboratories usually inform the estimated glomerular filtration rate based on serum creatinine, its elevation may lead to over diagnose a chronic renal failure, with the inherent personal and public health consequences. Creatine supplements are safe and do not cause renal disease. Reports of kidney damage associated with its use are scanty. However, creatine supplements should not be used in people with chronic renal disease or using potentially nephrotoxic medications.
Assuntos
Creatina/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Nefropatias/induzido quimicamente , Rim/efeitos dos fármacos , Rim/fisiopatologia , Creatinina/sangue , Humanos , Nefropatias/fisiopatologia , Fatores de RiscoRESUMO
Creatine supplements may transitorily rise serum creatinine levels and mimic a kidney disease. If its use is associated with a high protein diet, the resulting increase in blood urea nitrogen will increase the confusion. Since clinical laboratories usually inform the estimated glomerular filtration rate based on serum creatinine, its elevation may lead to over diagnose a chronic renal failure, with the inherent personal and public health consequences. Creatine supplements are safe and do not cause renal disease. Reports of kidney damage associated with its use are scanty. However, creatine supplements should not be used in people with chronic renal disease or using potentially nephrotoxic medications.
Assuntos
Humanos , Suplementos Nutricionais/efeitos adversos , Creatina/efeitos adversos , Rim/efeitos dos fármacos , Rim/fisiopatologia , Nefropatias/induzido quimicamente , Fatores de Risco , Creatinina/sangue , Nefropatias/fisiopatologiaRESUMO
The objective of this study was to evaluate the productive performance and carcass characteristics of broilers fed with creatine inclusion in the diet. Were evaluated one hundred and sixteen Cobb 500-day-old chicks were divided into four phases: 1 to 7, 8 to 21, 9 to 35 and 22 to 49 days of age, and four experimental diets were formulated, pre-initial, initial, growth and termination, respectively. All diets were produced based on corn and soybean meal. The birds were distributed in a completely randomized design with 0,10% of creatine in substitution to soybean meal and seven replicates. The variables studied were: feed intake (g/bird/day), weight gain (g/bird/day), final weight (g/bird), feed conversion (g/g), viability (%), noble cuts (g), edible offal (g) and carcass yield (%). There was no influence of the inclusion of creatine on the performance parameters of 7 - 21 and 35 days of age. However, there was improvement (P<0,05) in the feed conversion of 7 42 days of age. Body weight, carcass weight, thighs, wings, heart, gizzard, liver and carcass yield were not influenced by the inclusion of creatine, except for weight and breast yield for slaughter at 42 days (P<0,05). The inclusion of 0,10% of creatine in diets for broilers provided higher breast weight of birds slaughtered at 42 days and better feed conversion from 7 to 42 days of age.
Objetivou-se avaliar o desempenho produtivo e as características de carcaça de frangos de corte alimentados com inclusão de creatina na ração. Foram avaliados 196 pintainhos de um dia de idade da linhagem Cobb 500, divididos em quatro fases: 1 a 7, de 8 a 21, 22 a 33 e 34 a 49 dias de idade, e formuladas quatro dietas experimentais, pré-inicial, inicial, crescimento e terminação, respectivamente. Todas as dietas foram produzidas a base de milho e farelo de soja. As aves foram distribuídas em delineamento inteiramente casualizado, com 0,10% de creatina em substituição ao farelo de soja e sete repetições. As variáveis estudas foram: consumo de ração (g/ave/dia), ganho de peso (g/ave/dia), peso final (g/ave), conversão alimentar (g/g), viabilidade (%), cortes nobres (g), vísceras comestíveis (g) e rendimento de carcaça (%). Não houve influência da inclusão de creatina sobre os parâmetros de desempenho de 7 21 e 35 dias de idade. No entanto, houve melhora (P<0,05) na conversão alimentar de 7 42 dias de idade. Peso vivo, peso da carcaça, coxas, asas, coração, moela, fígado e rendimento de carcaças não foram influenciados pela inclusão de creatina, com exceção do peso e rendimento de peito para abate aos 42 dias (P<0,05). A inclusão de 0,10% de creatina em dietas para frangos de corte proporciona maior peso de peito de aves abatidas aos 42 dias e melhor conversão alimentar de 7 a 42 dias de idade.
Assuntos
Animais , Recém-Nascido , Creatina/administração & dosagem , Creatina/efeitos adversos , Galinhas/crescimento & desenvolvimento , Aditivos Alimentares , Ração AnimalRESUMO
The objective of this study was to evaluate the productive performance and carcass characteristics of broilers fed with creatine inclusion in the diet. Were evaluated one hundred and sixteen Cobb 500-day-old chicks were divided into four phases: 1 to 7, 8 to 21, 9 to 35 and 22 to 49 days of age, and four experimental diets were formulated, pre-initial, initial, growth and termination, respectively. All diets were produced based on corn and soybean meal. The birds were distributed in a completely randomized design with 0,10% of creatine in substitution to soybean meal and seven replicates. The variables studied were: feed intake (g/bird/day), weight gain (g/bird/day), final weight (g/bird), feed conversion (g/g), viability (%), noble cuts (g), edible offal (g) and carcass yield (%). There was no influence of the inclusion of creatine on the performance parameters of 7 - 21 and 35 days of age. However, there was improvement (P<0,05) in the feed conversion of 7 42 days of age. Body weight, carcass weight, thighs, wings, heart, gizzard, liver and carcass yield were not influenced by the inclusion of creatine, except for weight and breast yield for slaughter at 42 days (P<0,05). The inclusion of 0,10% of creatine in diets for broilers provided higher breast weight of birds slaughtered at 42 days and better feed conversion from 7 to 42 days of age.(AU)
Objetivou-se avaliar o desempenho produtivo e as características de carcaça de frangos de corte alimentados com inclusão de creatina na ração. Foram avaliados 196 pintainhos de um dia de idade da linhagem Cobb 500, divididos em quatro fases: 1 a 7, de 8 a 21, 22 a 33 e 34 a 49 dias de idade, e formuladas quatro dietas experimentais, pré-inicial, inicial, crescimento e terminação, respectivamente. Todas as dietas foram produzidas a base de milho e farelo de soja. As aves foram distribuídas em delineamento inteiramente casualizado, com 0,10% de creatina em substituição ao farelo de soja e sete repetições. As variáveis estudas foram: consumo de ração (g/ave/dia), ganho de peso (g/ave/dia), peso final (g/ave), conversão alimentar (g/g), viabilidade (%), cortes nobres (g), vísceras comestíveis (g) e rendimento de carcaça (%). Não houve influência da inclusão de creatina sobre os parâmetros de desempenho de 7 21 e 35 dias de idade. No entanto, houve melhora (P<0,05) na conversão alimentar de 7 42 dias de idade. Peso vivo, peso da carcaça, coxas, asas, coração, moela, fígado e rendimento de carcaças não foram influenciados pela inclusão de creatina, com exceção do peso e rendimento de peito para abate aos 42 dias (P<0,05). A inclusão de 0,10% de creatina em dietas para frangos de corte proporciona maior peso de peito de aves abatidas aos 42 dias e melhor conversão alimentar de 7 a 42 dias de idade.(AU)
Assuntos
Animais , Recém-Nascido , Galinhas/crescimento & desenvolvimento , Creatina/administração & dosagem , Creatina/efeitos adversos , Ração Animal , Aditivos AlimentaresRESUMO
BACKGROUND: Creatine (Cr) supplementation associated with resistance training produces greater muscular strength improvements in the upper compared with the lower body; however, no study has investigated if such region-specific results are seen with gains in muscle mass. AIM: We aimed to evaluate the effect of Cr supplementation in combination with resistance training on lean soft tissue changes in the upper and lower limbs and trunk in resistance-trained young adult men. METHODS: In a randomized, double-blind and placebo-controlled design, 43 resistance-trained men (22.7 ± 3.0 years, 72.9 ± 8.7 kg, 177.9 ± 5.7 cm, 23.0 ± 2.5 kg/m2) received either creatine (Cr, n = 22) or placebo (PLA, n = 21) over an 8-week study period. The supplementation protocol included a loading phase (7 days, four doses of 0.3 g/kg per day) and a maintenance phase (7 weeks, single dose of 0.03 g/kg per day). During the same period, subjects performed resistance training four times per week using the following two-way split routine: Monday and Thursday = pectoral, shoulders, triceps, and abdomen, Tuesday and Friday = back, biceps, thighs, and calves. Lean soft tissue of the upper limbs (ULLST), lower limbs (LLLST), and trunk (TLST) was assessed by dual-energy X-ray absorptiometry before and after the intervention. RESULTS: Both groups showed significant ( p < 0.001) improvements in ULLST, LLLST, TLST, and the Cr group achieved greater ( p < 0.001) increases in these outcomes compared with PLA. For the Cr group, improvements in ULLST (7.1 ± 2.9%) were higher than those observed in LLLST (3.2 ± 2.1%) and TLST (2.1 ± 2.2%). Otherwise, for PLA group there was no significant difference in the magnitude of segmental muscle hypertrophy (ULLST = 1.6 ± 3.0%; LLLST = 0.7 ± 2.8%; TLST = 0.7 ± 2.8%). CONCLUSION: Our results suggest that Cr supplementation can positively augment muscle hypertrophy in resistance-trained young adult men, particularly in the upper limbs.