Effect of Whey Protein Supplementation Associated With Resistance Training on Body Composition, Cellular Hydration, Phase Angle, Muscle Strength, Glycemic and Lipid Profile, Inflammatory and Oxidative Stress Markers in Trained Older Women
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 66
- 主要终点
- Change in cellular hydration
研究概览
简要总结
The main purpose of the present study was to investigate the effects of whey protein supplementation associated with resistance training on muscle strength, body composition, muscle quality, cellular hydration, cardiometabolic risk factors, inflammatory and oxidative stress markers in trained elderly women and to evaluate whether the timing of protein intake provide different responses on these variables.
详细描述
This study was carried out over a period of 26 weeks divided in two phases. The first phase of the study was an eight-week period (weeks 3-10), during which subjects were familiarized to RT. This RT period was conducted to standardize training status, and to overcome strong neural adaptations known to occur within the first few weeks of RT. Phase 2, supplementation phase, the participants was randomized in three groups and started 12 weeks dedicated to supplementation plus RT (weeks 13-24). At the beginning and the end of each phase of the experiment, two weeks were allocated for evaluations (weeks 1-2, 11-12 and 25-26) consisting of anthropometric, body composition, one repetition maximum tests (1RM), phase angle, body water, blood samples and dietary intake measurements.
Recruitment was carried out through newspaper and radio advertising, and home delivery of leaflets in the central area and residential neighborhoods. All participants completed health history and physical activity questionnaires and met the following inclusion criteria: 60 years old or more, physically independent, free from cardiac or orthopedic dysfunction, not receiving hormonal replacement and/or thyroid therapy, not using equipment that would prevent the accomplishment of protocols and tests, and not performing any regular physical exercise for 6 months preceding the beginning of the study. Participants have passed a diagnostic graded exercise stress test with 12-lead electrocardiogram reviewed by a cardiologist and were released with no restrictions for participation in this investigation. Eighty-three Brazilian older women (≥ 60 years old), volunteered to participate in this investigation. After individual interviews, thirteen volunteers were excluded because they did not meet the inclusion criteria. Seventy participants were submitted to a standardized resistance training (RT) program, for eight weeks. After the assessments, the participants were randomly divided into three groups according relative strength (ratio of total strength obtained on 1-RM tests by body mass): (1) whey protein pre- and placebo post- RT (whey protein-placebo, (2) placebo pre- and whey protein post- RT, and (3) placebo pre- and post- RT. A blinded researcher was responsible for generating random numbers for participant allocation. All groups were submitted to the same RT program and 66 participants completed the experiment. The reasons for withdrawal from the study was reported as personal reasons and transportation issues.
Written informed consent was obtained from all participants after a detailed description of investigation procedures was provided. This investigation was conducted according to the Declaration of Helsinki and was approved by the local University Ethics Committee (nº 1.700.756).
The paired t-test was used to analyze the effects (pre- vs post-) of the first phase. Two-way analysis of variance for repeated measures was applied for intra- and inter-group comparisons. When the baseline was different (ANOVA one-way), two-way analysis of covariance (ANCOVA) for repeated measures was applied for comparisons, with baseline scores used as covariates. When an F-ratio was significant, Fisher's post hoc test was employed to identify mean differences. The statistical power was determined to verify the statistical power of the analysis. For all statistical analyses, significance was accepted at P<0.05.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Factorial
- 主要目的
- Treatment
- 盲法
- Triple (Participant, Care Provider, Outcomes Assessor)
入排标准
- 年龄范围
- 60 Years 至 —（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •60 years old or more, physically independent, free from cardiac or orthopedic dysfunction, not receiving hormonal replacement therapy, and not performing any regular physical exercise more than once a week in the six months preceding the beginning of the investigation
- •Participants passed a diagnostic graded exercise stress test with a 12-lead electrocardiogram, reviewed by a cardiologist, and were released with no restrictions for participation in this investigation.
排除标准
- •All subjects not participating in 85% of the total sessions of training or withdraw
研究组 & 干预措施
Whey protein-placebo
Participants received a dose of 35 grams of whey protein before resistance training (RT) and a dose of 35 grams of maltodextrin (placebo) after RT.
Participants were personally supervised by physical education professionals with substantial RT experience. The sessions were performed 3 times per week on Mondays, Wednesdays, and Fridays, with 3 sets of 08-12 repetition maximums. The RT program was a whole-body program with eight exercises, including: chest press, seated row, triceps pushdown, preacher curl, horizontal leg press, knee extension, leg curl and seated calf raise. Participants were afforded a 1 to 2 min rest interval between sets and 2 to 3 min between each exercise. The training load was consistent with the prescribed number of repetitions for the three sets of each exercise.
干预措施: Whey protein-placebo (Dietary Supplement)
Placebo-whey protein
Participants received a dose of 35 grams of maltodextrin (placebo) before resistance training (RT) and a dose of 35 grams of whey protein after RT.
Participants were personally supervised by physical education professionals with substantial RT experience. The sessions were performed 3 times per week on Mondays, Wednesdays, and Fridays, with 3 sets of 08-12 repetition maximums. The RT program was a whole-body program with eight exercises, including: chest press, seated row, triceps pushdown, preacher curl, horizontal leg press, knee extension, leg curl and seated calf raise. Participants were afforded a 1 to 2 min rest interval between sets and 2 to 3 min between each exercise. The training load was consistent with the prescribed number of repetitions for the three sets of each exercise.
干预措施: Placebo-whey protein (Dietary Supplement)
Placebo-placebo
Participants received a dose of 35 grams of maltodextrin (placebo) before and after resistance training.
Participants were personally supervised by physical education professionals with substantial RT experience. The sessions were performed 3 times per week on Mondays, Wednesdays, and Fridays, with 3 sets of 08-12 repetition maximums. The RT program was a whole-body program with eight exercises, including: chest press, seated row, triceps pushdown, preacher curl, horizontal leg press, knee extension, leg curl and seated calf raise. Participants were afforded a 1 to 2 min rest interval between sets and 2 to 3 min between each exercise. The training load was consistent with the prescribed number of repetitions for the three sets of each exercise.
干预措施: Placebo-placebo (Dietary Supplement)
结局指标
主要结局
Change in cellular hydration
时间窗: baseline 1; after 8 weeks (baseline2) and after 12 weeks
Spectral bioelectrical impedance device (Xitron Hydra, model 4200, Xitron Technologies, San Diego, CA, USA) was used to estimate the intracellular water (ICW), extracellular water (ECW), and total body water (TBW). The results are presented in liters (L)
Change in body composition
时间窗: baseline 1; after 8 weeks (baseline2) and after 12 weeks
Whole-body dual-energy X-ray absorptiometry (DXA) (Lunar Prodigy) was used to assess lean mass and fat mass and its segments. The total skeletal muscle mass (SMM) was estimated by the predictive equation proposed by Kim et al. (Kim et al., 2004). The results are presented in kg.
Change in CATALASE (CAT)
时间窗: Baseline and 12 weeks
The CAT analysis is by measuring the decay in concentration of hydrogen peroxide , and oxygen generation using the technique described by literature. The reading of the CAT reaction was carried out in a spectrophotometer, ThermoSpectronic® brand, model HELIOS-α (Waltham, MA, USA) at a wavelength of 240 nm.
Change in superoxide dismutase (SOD)
时间窗: Baseline and 12 weeks
The SOD activity in erythrocytes was determined using the pyrogallol method described by literature. The reading of SOD reaction is performed in a spectrophotometer, thermoSpectronic® brand, model HELIOS-α (Waltham, MA, USA) at a wavelength of 420 nm.
Change in Phase Angle
时间窗: baseline 1; after 8 weeks (baseline2) and after 12 weeks
Spectral bioelectrical impedance device (Xitron Hydra, model 4200, San Diego, CA, USA) was used to estimate the resistance (R), and reactance (Xc), and subsequently the phase angle (PhA) was calculated as arc-tangent (Xc/R) x 180°/π. The results are presented in degree
Change in C-reactive protein (CRP)
时间窗: baseline 1; after 8 weeks (baseline2) and after 12 weeks
Measurements of serum levels of high-sensitivity CRP were carried out using a biochemical auto-analyzer system (Dimension Max - Siemens Dade Behring) according to established methods in the literature consistent with the manufacturer's recommendations. The results are presented in milligrams per decilitre (mg/dL).
Change in oxidative stress
时间窗: baseline 1; after 8 weeks (baseline2) and after 12 weeks
For measurements, advanced oxidation protein products (AOPP) were determined in the plasma using a semiautomatic method. AOPP concentrations were expressed as micromoles per liter (μmol/L). Total plasma antioxidant capacity (TRAP) was determined by the chemiluminescence method for the induction time of 2.2 azo-bis (2-amidinopropane) and calibrated with Trolox analogue of vitamin E. TRAP values were expressed in μmol of Trolox.
Change in lipid profile
时间窗: baseline 1; after 8 weeks (baseline2) and after 12 weeks
Measurements of serum levels of total cholesterol (TC), high-density lipoprotein (HDL-C) and triglycerides (TG) were determined using a biochemical auto-analyzer system (Dimension Max - Siemens Dade Behring) according to established methods in the literature consistent with the manufacturer's recommendations. For the determination of LDL-c was used the Friedewald equation: LDL-c=TC - (HDL-c + TG / 5). The Castelli Index I was calculated by dividing the total cholesterol concentration (TC) by the concentration of HDL-c (CT / HDL-c), while the Castelli Index II was determined from concentration of LDL-c divided by the concentration of HDL-c (LDL-c / HDL-c)
Change in inflammatory markers
时间窗: Baseline and 12 weeks
Tumor Necrosis Factor -α (TNF-α) and Interleukin-6 (IL-6) were determined by enzyme-linked immunosorbent assay (ELISA), according to the specifications of the manufacturer (Quantikine High Sensitivity Kit, Minneapolis) and performed in a microplate reader Perkin Elmer, model EnSpire (Waltham, MA, USA). All samples were determined in duplicate to guarantee the precision of the results. The results are presented in picograms per milliliter (pg/ml).
Change in glucose, insulin and HOMA-IR
时间窗: baseline 1; after 8 weeks (baseline2) and after 12 weeks
Measurements of serum levels of glucose (GLU) were determined using a biochemical auto-analyzer system (Dimension Max - Siemens Dade Behring).Insulin was determined by the chemiluminescence method (LIASON equipment) and the Homeostasis Assessment Model (HOMA-IR) was calculated by the formula: Insulin fasting (μUI / mL) x Glucose fasting (mmol / L) / 22.5.
change in Muscular strength
时间窗: baseline 1; after 8 weeks (baseline2) and after 12 weeks
Maximal dynamic strength was evaluated using the 1RM test assessed on chest press, knee extension, and preacher curl exercises performed in this exact order. Testing for each exercise was preceded by a warm-up set (6-10 repetitions), with approximately 50% of the estimated load used in the first attempt of the 1RM. This warm-up was also used to familiarize the subjects with the testing equipment and lifting technique. The testing procedure was initiated 2 minutes after the warm-up. The subjects were instructed to try to accomplish two repetitions with the imposed load in three attempts in both exercises. The rest period was 3 to 5 min between each attempt, and 5 min between exercises. The 1RM was recorded as the last resistance lifted in which the subject was able to complete only one single maximal execution
次要结局
- Change in blood pressure(baseline 1; after 8 weeks (baseline2) and after 12 weeks)
- Dietary intake(baseline 1; after 8 weeks (baseline2) and after 12 weeks)
- Change in anthropometric measurements(baseline 1; after 8 weeks (baseline2) and after 12 weeks)
研究者
Hellen Clair Garcêz Nabuco
master degree
Universidade Estadual de Londrina