Adding Whey Protein to diet and weight training

By on June 22, 2017 in Uncategorized


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Resting Metabolic Rate
Resting metabolic rate (RMR) was assessed prior to and following the eight week intervention period using a ParvoMedics TrueOne® metabolic cart after a 45-minute resting period in which participants were instructed to remain as quiet and motionless as possible in a dimly lit room. Participants were instructed to freely inhale and exhale throughout the test. Oxygen uptake was measured from expired air and required the use of a plastic canopy, preventing the need for a facemask or mouthpiece, which may artificially elevate resting metabolic rate. Research assistants remained in the room to ensure that participants did not fall asleep.
Caloric-restricted diet
All subjects were provided with an individualized caloric-restricted diet based on individual data (body mass, body composition, resting metabolic rate, etc.). Diets were designed by an industry consultant with prior experience consulting with physique athletes during pre-contest preparation. The caloric-restricted diet was designed as an eight-week “cut diet” for reducing body fat, and used a modified carbohydrate-restricted diet approach (percent of total calories for workout days were 30% carbohydrates, 35% protein and 35% fat and for off days were 25% carbohydrates, 40% protein and 35% fat).

Each individual’s daily caloric and macronutrient intake was determined using the Harris Benedict formula with an activity factor of 1.35 (lightly active individual engaging in light exercise 1-3 days/week) for workout days and 1.125 (sedentary individual) for off days. Subjects were given a diet card (See Figure 1) for work out days and off days that listed the total caloric goal with three meal options per meal to attain the desired intake. The dietary intake needs were re-calculated after four weeks of the study to account for any changes in body mass. Subjects were required to maintain the diet provided for them for the entire eight-week study period and weekly interviews with subjects were incorporated to help achieve compliance.
Supplementation Protocol
In a single-blind design, each participant was randomly assigned an eight-week supplementation protocol in one of two groups. Participants assigned to the protein supplement group consumed 28 g of a whey protein nutritional supplement (Scivation Whey, Scivation, Inc.) prior to and following each workout for a total of 56g. Subjects in the control group ingested 28g of a carbohydrate based nutritional supplement (POWERADE ®) prior to and following each workout, for a total of 56g per workout. Each subject was given a 4-week supply of their supplement with specific instructions on how to mix and when to consume. Subjects returned to the lab every four weeks to receive additional supplement. Subjects had to agree to refrain from consuming any other nutritional supplements during the study period.
Resistance training protocol
Participants engaged in a supervised progressive bodybuilding split style resistance-training program consisting of 60-90 minutes of training four days per week for eight weeks (Day 1: Chest/Triceps, Day 2: Legs, Day 3: shoulders, Day 4: Back/Biceps).




Although the body parts trained remained consistent throughout the eight weeks, the specific exercises used for each body part alternated and repeated every other week. Subjects performed 3-4 sets per exercise with two-minute rest periods. During weeks 1 & 2 subjects completed 4-5 reps per set and every two subsequent weeks two reps were added per set resulting in subjects performing 10-11 reps per set during weeks 7 & 8. Subjects were provided and instructed to maintain their training log throughout the eight-week training period and returned to the lab every four weeks to have their individual training logs reviewed. Subjects (both treatment and control) not progressing through their program or complying with the stated nutrition and supplement requirements were dismissed from the study.
Statistical Analyses
Data are expressed as means ± SE. To determine if the whey protein provided an additive benefit to the caloric restricted diet and resistance training program data was analyzed (SigmaSat 3.5) using a priori paired and unpaired t-tests to assess changes over time and between group means, respectively. Tukey’s Test was used for post hoc analysis. Intraclass correlation coefficients (ICC) were performed to examine the test-retest reliability of the performance tests. The significance level was set at α = 0.05.

Body Composition
There were no differences in body mass change between the whey and CON groups, however both groups lost body mass (2.4±0.7 kg; p<.05) during the trial period, suggesting the calorie restricted diet was successful. (See Figure 2) The whey group maintained lean body mass during the trial while the CON group had a 1.4±0.1% (pre: 67.8±2.5 kg vs. post: 66.9±2.5 kg) loss in lean body mass (p<.05). (See Figure 3) Finally, the whey group lost 20.9±3.3% (11.9±2.1 kg vs 9.4±1.6 kg) fat mass (p<.05) and while the CON group non significantly lost 1.4±0.7 kg fat mass (p>.05) the difference in fat mass lost between groups post study was not different (p=.20).
Resting metabolic rate, in terms of calories burned per minute, decreased in the whey group (p<.05) but not in the CON group (p>.05), though the difference in changes between the groups was not significant (p=.19). Not surprisingly, this trend held when translating these data to a 24- hr period (whey: 2002±101 vs. 1286±34 kcals/day; CON: 1898±261 vs. 1586±49 kcals/day).
Muscular Strength & Local Muscular Endurance
Both muscular strength and local muscular endurance were measured for the lower body (squat) and upper body (bench press). There was no difference (p=.22) in lower body strength changes following the study between the groups, as both the whey (pre: 133±5 vs. post: 144±3 kg; p<.05) and CON (pre: 124±10 vs. post: 128±12 kg; p<.05) groups showed significant improvements.

Upper body tests showed a different result, as there was a difference in how the groups responded (p<.05), with the whey group increasing strength (pre: 103±3 vs. post: 107±4 kg; p<.05) while the CON did not change (pre: 101±3 vs. post: 97±2 kg; p>.05). (See Figure 7)

Both groups increased squat repetitions (p<.05) compared to pre (whey: 12±2 vs. 15±2 reps; CON: 14±1 vs. 19±1 reps) and the increase was greater in the CON group (p<.05). Differences were found with upper body muscular endurance, with the CON group having a greater increase in repetitions (whey: 9±0.3 vs. 9±0.3 reps; CON: 7±1 vs. 9±0.2 reps; p<.05). ICCs for the lower body 1RM squat test was R = 0.999, 80% 1RM squat test for reps was R = 0.991, upper body 1RM bench press test was R = 0.684, and 80% 1RM bench press test for reps was R = 0.756. (See Figure 8)
Place Figures 7 & 8 here.


The aim of this study was to determine the effectiveness of a whey protein supplement in conjunction with a hypocaloric diet, on body composition, resting metabolic rate, and muscular fitness in healthy resistance trained males. Prior reports suggest maintaining muscle mass while reducing fat mass is difficult, yet we hypothesized that the whey supplement would elicit an effect on muscle recovery from exercise and maintain muscle mass and muscular fitness (5,18).
Both whey and CON groups engaged in identical, supervised resistance training programs, and received individualized hypocaloric diets for eight weeks; therefore, changes in body composition and muscular fitness are most likely the result of the protein supplement, compared to the ingestion of the carbohydrate placebo supplement. This is an important discovery because protein supplements such as whey are often relied upon to maintain or improve muscle mass, in order to aid muscle recovery, enhance athletic performance, and to reduce the risk of sarcopenia, especially in older adults (5,18).

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