Protein Intake and Physical Performance

Effects of Increased Protein Intake and Exercise Training on Body Composition, Cardiovascular Health and Physical Performance

A primary aim of the current proposal is to compare the effect of daily consumption of healthy lean protein as either whey protein (2 meals per day) or whole food (25% of total daily caloric intake) consumed as 6 small meals throughout the day, one of which is consumed immediately following exercise training (within 30 min) and another 2 hours prior to going to bed at night, over a 16 week period on muscle and fat mass, cardiovascular health, aerobic fitness, glucose, insulin, blood lipids, heart rate and muscle strength in overweight men and women.

Study Overview

• Status: Completed
• Conditions: Physical Performance
• Intervention / Treatment: Behavioral: Whey Protein and exercise training; Behavioral: Food Protein and exercise training

Detailed Description

The primary purpose of this study is to examine the effects of increased healthy protein intake (25% of daily caloric intake as protein; 25% as healthy fats and oils; 50% as complex, unrefined carbohydrates) consumed as 6 small meals during the day in combination with exercise training 4 times per week, over a 16 week period in 25 overweight, but healthy males and females (30-60 yrs old). A secondary purpose is to compare the effects of consuming two of the 6 small meals during the day comprised of whole food protein source servings 20g/serving) with a matched group consuming whey protein for 2 daily protein servings (20g/serving). In the case of both groups, 1 serving will be consumed immediately following exercise [within 30 minutes] and 1 serving will be consumed 2 hours before going to bed. On non-exercise days, all participants will continue to consume 6 small meals per day in the same ratio of 25% lean protein, 25% healthy fats and oils, and 50% complex, unrefined carbohydrates but the groups will differ only in the composition of the last meal of the day consumed 2 hours before going to bed in which one group will consume protein (20g/serving) as whole food protein sources and the other group will consume a single serving of a whey protein supplement. The primary purpose of this study is to quantify changes in the following health outcomes at baseline and 16 weeks: total body muscle mass and fat mass (iDXA); abdominal fat mass (most highly related to cardiovascular and metabolic disease risk); blood sugar (glucose); blood lipids; insulin, aerobic fitness (assessed with a submaximal exercise test); and muscular strength (measured by 1 repetition maximum (RM) of the chest and leg press). The following additional measures will be assessed at baseline and 16 weeks: waist circumference; body weight, heart rate, blood pressure, and hunger (Visual Analog Scales).

• Study Type: Interventional
• Enrollment (Actual): 25
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 30 years to 60 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Each participant was screened prior to participating in the study using the Health and Fitness History, Physical Activity, and Physical Activity Readiness questionnaires administered by the investigators.
• Medical clearance was secured from the participant's primary care physician to verify no cardiovascular,metabolic or orthopedic issues that would prohibit them from performing the exercises for the duration of the study period
• Depending on the outcome of the health history, fitness and activity questionnaires and the physician's clearance, participants were informed of eligibility to participate in the study. A group meeting was scheduled for all eligible and interested participants to review the entire study. This process took place prior to administering any tests.

Exclusion Criteria:

• Participants were excluded if they smoked, had a whey protein intolerance, or orthopedic conditions that prohibited them from engaging in strenuous exercise

Study Plan

How is the study designed?

Design Details

• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Whey Protein and exercise training; Six meals per day of 20 grams of protein, two of which were whey protein and 4 days per week of exercise training..	Behavioral: Whey Protein and exercise training; Six meals per day four of which were whole food and two of whey protein for an overall percentage of macronutrient intake of 25% protein and 4 days per week of exercise training
Experimental: Food Protein and exercise training; Six meals per day of 20 grams of protein, all of which were whole food protein and 4 days per week of exercise training.	Behavioral: Food Protein and exercise training; Six meals per day all of which were whole food protein for an overall percentage of macronutrient intake of 25% protein and 4 days per week of exercise training

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Athletic Performance	Changes in one repetition maximum muscular strength of upper and lower body	baseline and post 16 week intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total and Regional Body Composition	Changes in total and regional body fat assessed by dual energy xray	baseline and post 16 week intervention

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cardiometabolic Hormones	Changes in plasma insulin levels	baseline and post 16 week intervention
Aerobic Fitness	Changes in oxygen consumption	baseline and post 12 week intervention
Hunger Ratings	Changes in hunger visual analog scale ratings	baseline and post 12 week intervention
Blood Lipids	Changes in total, LDL, HDL cholesterol	baseline and post 12 week intervention
Blood Pressure	Changes in systolic and diastolic blood pressure	baseline and post 12 week intervention

Collaborators and Investigators

• Sponsor: Skidmore College

Study record dates

Study Major Dates

• Study Start: December 1, 2010
• Primary Completion (Actual): June 1, 2011
• Study Completion (Actual): August 1, 2013

Study Registration Dates

• First Submitted: October 29, 2015
• First Submitted That Met QC Criteria: October 30, 2015
• First Posted (Estimate): November 3, 2015

Study Record Updates

• Last Update Posted (Estimate): November 3, 2015
• Last Update Submitted That Met QC Criteria: October 30, 2015
• Last Verified: October 1, 2015

More Information

Terms related to this study

• Other Study ID Numbers: 1012-227