Glucose and Motivation States

Impact of Blood Glucose on Motivation States: A Double-Blind Placebo-Controlled Study

The purpose of this study is to evaluate how motivation is impacted by exercise and beverage consumption. You will be asked to report to our lab for 5 visits each separated by 2+ days over a period of 2-3 weeks.

Study Overview

• Status: Recruiting
• Conditions: Motivation
• Intervention / Treatment: Behavioral: Exercise; Dietary supplement: Sugar Drink; Dietary supplement: Non-sugar beverage

• Study Type: Interventional
• Enrollment (Estimated): 40
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Marcus Kilpatrick, PhD; Phone Number: 813-362-6696; Email: mkilpatrick@usf.edu
• Study Contact Backup: Name: Andrea Barrows, MS; Phone Number: 813-974-8127; Email: andreabarrows@usf.edu

Study Locations

• United States
  • Florida
    • Tampa, Florida, United States, 33620
      • Recruiting
      • University of South Florida
      • Contact: Marcus Kilpatrick, PhD; Phone Number: 813-362-6696; Email: mkilpatrick@usf.edu
      • Contact: Andrea Barrows, MS; Phone Number: 813-974-8127; Email: andreabarrows@usf.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Body mass index 18-30 m/kg^2
• Health Status: generally healthy; no cardiopulmonary/metabolic/orthopedic disease or limitations
• Blood Pressure: excluded with SBP of 130+ mmHg or DBP of 80+ mmHg
• Glucose Status: excluded and instructed to seek medical consultation if fasting values are <70 mg/dl or >125 mg/dl; included but encouraged to seek medical consultation if fasting values are 100-125 mg/dl

Exclusion Criteria:

• None

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Exercise + sugar drink	Behavioral: Exercise; Exercise 30 minutes at moderate intensity (10% below ventilatory threshold); Dietary supplement: Sugar Drink; Consume 250mL beverage (water + 6 tablespoons table sugar)
Placebo Comparator: Exercise + non-sugar drink	Behavioral: Exercise; Exercise 30 minutes at moderate intensity (10% below ventilatory threshold); Dietary supplement: Non-sugar beverage; Consume 250mL beverage (water + 1.5 teaspoons of stevia powder)
Active Comparator: Rest + sugar drink	Dietary supplement: Sugar Drink; Consume 250mL beverage (water + 6 tablespoons table sugar)
Placebo Comparator: Rest + non-sugar drink	Dietary supplement: Non-sugar beverage; Consume 250mL beverage (water + 1.5 teaspoons of stevia powder)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
State Motivation to Move	Score on movement subscale of Cravings for Rest and Volitional Energy Expenditure Survey (0 is lowest, 100 is highest)	60 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
State motivation to rest	Score on rest subscale of Cravings for Rest and Volitional Energy Expenditure Survey (0 is lowest, 100 is highest)	60 minutes

Collaborators and Investigators

• Sponsor: University of South Florida

Study record dates

Study Major Dates

• Study Start (Actual): October 30, 2025
• Primary Completion (Estimated): August 1, 2026
• Study Completion (Estimated): August 1, 2026

Study Registration Dates

• First Submitted: November 19, 2025
• First Submitted That Met QC Criteria: November 19, 2025
• First Posted (Actual): November 28, 2025

Study Record Updates

• Last Update Posted (Actual): November 28, 2025
• Last Update Submitted That Met QC Criteria: November 19, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena; Food and Beverages; Beverages; Exercise; Sugar-Sweetened Beverages
• Other Study ID Numbers: STUDY009043

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

IPD Plan Description

Individual deidentified participant data (including data dictionaries) will be shared. This includes individual participant data that underlie the results reported in any aspect of a published article (text, tables, figures, and appendices).

Other documents that will be available include the study protocol, statistical analysis plan, informed consent form, and analytic code. The data will be available immediately after publication with no end date. Data will be shared with researchers who provide a methodologically sound proposal to achieve aims in the approved proposal. Proposals should be directed to Dr. Garrett Ash at Yale University (garrett.ash@yale.edu). To gain access, data requesters will need to sign a data access agreement.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No