Breakfast Consumption and Energy Balance in Active Adult Males

Ohio University10 enrolled

Overview

Exercising in the fasted state results in greater fat oxidation during exercise and results in decreased caloric intake in the meals after exercise. However, the studies that examine fasted vs. fed exercise utilize a carbohydrate-based breakfast, which can increase blood glucose and insulin concentrations, which is considered a negative consequence. A protein breakfast, which can increase satiety and rest of day energy intake could also increase resting energy expenditure as well as fat oxidation during exercise. However, comparisons between fasting exercise and pre-exercise breakfast macronutrient intake (i.e., carbohydrate vs. protein) have not been made. Therefore the purpose of this study is to investigate if eating breakfast and the composition of this breakfast before exercise has an effect on the food eaten throughout the rest of the day.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Enrollment

Conditions

Energy Intake Substrate Utilization Hormones Satiety

Interventions

Maltodextrin supplementDIETARY_SUPPLEMENT

maltodextrin (25g in 12 oz water) 1 hour pre-exercise

Whey supplementDIETARY_SUPPLEMENT

whey (25g in 12 oz water) 1 hour pre-exercise

WaterDIETARY_SUPPLEMENT

non-caloric control (12 oz flavored water) 1 hour pre-exercise

Maltodextrin supplementDIETARY_SUPPLEMENT

maltodextrin (25g in 12 oz water) with no exercise

Eligibility

Sex: MALEMin age: 18 YearsMax age: 45 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * 18-45 years old * regularly participate in exercise for at least 150 min per week * run at least 3 days per week for 30 minutes * able to complete a VO2max test * able to exercise for 45 min moderate intensity exercise at one time without breaks Exclusion Criteria: * not participating in structured exercise of 150 min/week for the past 6 months * not running at least 3 days per week for 30 minutes * not attaining a VO2max of 50 ml/kg/min (60th percentile fitness classification according to the American College of Sports Medicine) * currently smoke or quit smoking less than one year ago. * diagnosed with or are being treated for a cardiovascular disease, high blood pressure, fibromyalgia, irritable bowel syndrome or a metabolic disorder such as diabetes, thyroid disorder, or high cholesterol. * food allergies or sensitivities. * not willing to have blood drawn on 4 occasions during each trial (16 total times)

Outcomes

Primary Outcomes

Change in energy expenditure

Measured via indirect calorimetry

Time frame: immediately pre-breakfast, immediately post-breakfast, immediately pre-exercise, and immediately post-exercise

Change in lunch energy intake

measured via standardized lunch buffet

Time frame: 60 min post-exercise

Change in dinner energy intake

weight of food returned the following day

Time frame: Day 1 (trial 1); between Days 6 and 8 (trial 2); between Days 11 and 15 (trial 3); and between Days 16 and 22 (trial 4)

Change in appetite

measured via circulating hormones

Time frame: immediately pre-breakfast, immediately post-breakfast, immediately post-exercise, and immediately pre-lunch

Change in blood glucose

measured via fingerstick blood assessment

Time frame: immediately pre-breakfast, immediately post-breakfast, immediately post-exercise, immediately pre-lunch, and immediately pre-dinner

Change in subjective hunger

measured via 100mm visual analogue scale, higher scores indicate greater hunger

Time frame: baseline, immediately pre-breakfast, immediately post-breakfast, immediately post-exercise, immediately pre-lunch, immediately post-lunch, immediately pre-dinner, and immediately post-dinner