Whey Protein Supplementation Associated With Resistance Training on Health Indicators in Trained Older Women
- Conditions
- Body CompositionHealthy
- Interventions
- Dietary Supplement: Placebo-placeboDietary Supplement: Whey protein-placeboDietary Supplement: Placebo-whey protein
- Registration Number
- NCT03247192
- Lead Sponsor
- Universidade Estadual de Londrina
- Brief Summary
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.
- Detailed Description
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.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Female
- Target Recruitment
- 66
- 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.
- All subjects not participating in 85% of the total sessions of training or withdraw
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- FACTORIAL
- Arm && Interventions
Group Intervention Description Placebo-placebo 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. Whey protein-placebo 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. Placebo-whey protein 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.
- Primary Outcome Measures
Name Time Method Change in body composition 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) 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) 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 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) 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 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 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 cellular hydration 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 inflammatory markers 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 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 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
- Secondary Outcome Measures
Name Time Method Change in blood pressure baseline 1; after 8 weeks (baseline2) and after 12 weeks Resting BP assessment was performed using automatic, oscillometric equipment (Omron - 7113). Participants attended the laboratory on three different days and, during each visit, remained seated at rest for 10 min with the cuff of the equipment in place on the right arm. Subsequently, several BP measurements were performed at one-minute intervals in order to obtain three consecutive measurements where the difference in systolic BP (SBP) and diastolic BP (DBP) readings differed by no more than 4 mmHg. The average of the three measurements for each day was averaged across the three visits.
Dietary intake baseline 1; after 8 weeks (baseline2) and after 12 weeks Food consumption were assessed by the 24-hour dietary recall method applied on two non-consecutive days of the week, with the aid of a photographic record taken during an interview. The homemade measurements of the nutritional values of food and supplementation were converted into grams and milliliters by the online software Virtual Nutri Plus (Keeple®, Rio de Janeiro, Rio de Janeiro, Brazil) for diet analysis. Some foods were not found in the program database and therefore items were added from food tables.
Change in anthropometric measurements baseline 1; after 8 weeks (baseline2) and after 12 weeks Body mass was measured to the nearest 0.1 kg using a calibrated electronic scale scale (Balmak), with subjects wearing light workout clothing and no shoes. Height was measured using a stadiometer to the nearest 0.1 cm while subjects were standing without shoes. Body mass index was calculated as the body mass in kilograms divided by the square of the height in meters. We also collected data on waist circumference (WC) and (HC) hip, using a flexible and inelastic tape measure. WC was obtained at the midpoint between the last rib and the iliac crest at the time of expiration and the WC was measured in the region of greater perimeter between the waist and the thigh. Two measurements were used to measure each circumference. In situations in which the difference between the measurements was greater than 0.5 cm a third measurement was performed, with the value of the median being adopted as reference. All measurements were performed by the same evaluator.