Effects of Alpha-GPC on Muscle Power, GH Levels, and Cognitive Function

Purpose: To determine the effects of low dose and high dose Alpha-GPC on cognitive performance, muscle performance, and serum growth hormone levels.

Design: Randomized, three-arm, within-subject crossover

Study Participants: 21 apparently healthy men to be recruited at a single investigational center in Northeast Ohio

4 Study Visits

Study Visit 1: Participants will be screened for participation (i.e., medical history, routine blood work, background baseline diet)

Study Visit 2: Participants will ingest one of three supplements (a low dose α-GPC, a high dose α-GPC, or a placebo). Subjects will complete visual analog scale (VAS) questionnaires (assessing mood, motivation, alertness, and concentration) and a cognitive battery (Stroop, Flanker, and N-Back tests) 60 min post ingestion and approximately 3 hours post-ingestion, undergo upper body and lower body power testing and a lower body bout of moderate-intensity exercise 90 min post-ingestion. Also, subjects will undergo blood draws for levels of growth hormone at baseline (prior to supplementation) and 5, 15, 30, and 60 min post lower body bout of exercise. Vital signs and comprehensive side effect profile/ adverse event monitoring will take place throughout the duration of the study. The study will be conducted following ICH-GCP guidelines to ensure subject safety and scientific integrity of the data.

Study Visit 3 and 4 Identical to visit 2 with exception of different supplementation being provided. Supplement administration was randomized using a Latin square approach to reduce variability and enhance statistical power

Primary Outcomes: Upper and lower body peak force production, peak power production, and peak velocity

Secondary Outcomes: Cognitive performance on the Stroop test, Flanker, and N-Back test, serum growth hormone levels, mood, motivation, alertness, and concentration (as assessed by visual analog scales).

Tertiary/Safety Outcomes: Vital signs, side effect profile/AE monitoring

Study Overview

• Status: Completed
• Conditions: Cognition - Other; Strength Outcomes
• Intervention / Treatment: Dietary supplement: Placebo; Dietary supplement: 315 mg Alpha-GPC; Dietary supplement: 630 mg Alpha-GPC

Detailed Description

DIET:

• All subjects will be asked to maintain their usual dietary habits throughout the study.
• At screening, all subjects will complete a 24-hour diet recall from the day prior while refraining from any nutrients that might affect choline.
• To replicate screening conditions as closely as possible, subjects will follow their previously recorded 24-hour diet record and fast for 8 hours prior to each laboratory visit.
• An online application (Nutritionix) will be used to analyze their dietary consumption.

BLOODWORK:

•Blood draws will take place during each laboratory visit, and they will be performed by a study nurse or phlebotomist. At screening a single blood draw will be performed with a total blood volume of approximately 12 mL. During visits 2-4 serial blood draws will be performed before and 5-, 15-, 30-, and 60-min post ingestion of the investigational product. During visits 2-4, an intra-venous catheter (flexible tubing to enable blood sampling) will be inserted into an upper extremity vein. Blood samples will be collected up to 5 times over 4 hours.

EXERCISE TRAINING AND PHYSICAL ACTIVITY CONTROL

•Subjects will be asked to maintain their activities of daily living and abstain from exercise for 48 hours prior to each trial.

TEST PRODUCTS

• After qualifying for the study, subjects will be randomly assigned to receive a placebo, a low dose of α-GPC, and a high dose of α-GPC using a Latin Square design.

  • Low dose of α-GPC (350 mg)
  • High dose of α-GPC (700 mg)
  • Placebo (containing maltodextrin)
• Supplements will be provided in identical-looking capsules with label directions and Study Protocol Number.
• Subjects will consume each supplement in the presence of the medical staff.
• There will be no less than one week between each trial, though this may be longer depending on scheduling.
• As stated earlier, subjects who withdraw from the study prior to completing all three trials may be replaced.

DETAILED STUDY PROCEDURES

Visit 1 (Screening)

• Medical history, safety blood work (CBC, CMP, and Lipid Panel)
• Body composition (bioimpedance-BIA)
• Baseline diet (24hr recall).
• Body weight
• Familiarization trial for the cognitive battery (Stroop, Flanker, and N-Back test).

Visits 2-4

• Subjective feelings of mood, motivation, alertness, and concentration will be assessed 60 minutes post ingestion and approximately 3 hours post-ingestion. All assessments will be made using 100 mm anchored visual analogue scales (VAS).

• Three repetitions of the Stroop (2-min tests), Flanker, and N-Back (90s tests) tests will be assessed 60 minutes post ingestion and approximately 3 hours post-ingestion.

  • Stroop - https://www.psytoolkit.org/lessons/stroop.html
  • Flanker - https://www.psytoolkit.org/experiment-library/flanker.html
  • N-Back - https://www.lumosity.com/app/v4/games/speed-match-overdrive-web
• Upper and lower body muscular power will be assessed with a Tendo unit. For the upper body, the bench press throw using a submaximal load (i.e., 50% of 1RM) will be performed on a Smith machine. For the lower body, a vertical jump will be performed. Both tests will be performed 90 minutes post-ingestion.
• Moderate intensity lower body exercise bout consisting of 6 sets of 10 repetitions at 70% of 1RM of squats using a metronome for cadence (15 reps per min) on a Smith machine approximately 2 hours post-ingestion.
• Growth hormone will be measured via blood draw before supplementation ingestion and 5, 15, 30, and 60 min post lower body exercise bout.
• Body weight
• Vital signs will be assessed prior to supplementation, 60 minutes post ingestion, and approximately 3.5 hr post-ingestion.

Study Schematic:

Informed Consent: Visit 1 Inclusion/Exclusion Criteria: Visit 1 Medical History: Visit 1 Height, weight, and BMI: Visits 1, 2, 3, 4 24-hr Dietary recall: Visit 1 CBC, CMP, Lipid Panel: Visit 1 Vitals (HR and BP): Visit 1 Bioimpedance Analysis (BIA) for percent body fat: Visit 1 Bench Press Throw for Upper Body Power (Tendo) @ 50%1RM approximately 90 minutes post-ingestion: Visits 2, 3, 4 Vertical Jump for Lower Body Power (Tendo) approximately 90 minutes post-ingestion: Visits 2, 3, 4 Lower body exercise bout consisting of squats on a Smith machine (6 x 10 @70%1RM) beginning approximately 2 hours post-ingestion: Visits 2, 3, 4 Cognitive performance battery (N-back, Flanker, Stroop) (60 min post ingestion and approximately 3 hours post-ingestion on visits 2-4 only): Visits 1, 2, 3, 4 Serum GH (before ingestion and 5, 15, 30, and 60 min post lower body exercise bout): Visits 1, 2, 3, 4 VAS (mood, motivation, alertness, and concentration) 60 min post ingestion and approximately 3 hours post-ingestion): Visits 2, 3, 4 Vitals (HR and BP) monitoring (at baseline, 60 min post ingestion, and approximately 3.5 hours post-ingestion): Visits 2, 3, 4 24 hr Diet Records/Analysis/Repeat: Visits 2, 3, 4 Protocol Compliance (diet and physical activity log check): Visits 2, 3, 4 Dispense Test Product: Visits 2, 3, 4 Adverse Events Monitoring: Visits 1, 2, 3, 4

METHODS AND INSTRUMENTATION:

• Health history will be determined using a standardized (IRB-approved) questionnaire.
• Heart rate and blood pressure will be measured using an automated sphygmomanometer.
• Body composition will be measured using a bioimpedance device (InBody 570- https://inbodyusa.com/products/inbody570/).
• Standing height will be determined using a wall-mounted stadiometer.
• Body weight and height will be measured using a Seca Medical Scale (https://www.hogentogler.com/seca/769-physician-scale.asp?gclid=EAIaIQobChMIxoqxi6ef8wIVtmpvBB34QAwzEAQYAyABEgIVIPD_BwE).
• Upper and lower body muscular power will be determined using a Tendo power analyzer (Tendo Sport- https://www.tendosport.com/products/tendo-unit/overview/)
• A Central Lab (LabCorp, Dublin, OH) will be utilized to transport and analyze all blood samples.
• Diet records will be analyzed using the online application (Nutritionix).

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Ohio
    • Canfield, Ohio, United States, 44406
      • Center for Applied Health Sciences

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Voluntarily provide signed and dated informed consent.
• Be in good health as determined by medical history and routine blood chemistries.
• Age between 25 and 55 years (inclusive).
• Body Mass Index of 18.5-34.9 (inclusive).
• Body weight of at least 120 pounds.
• Resistance training history of at least 2 years.
• Normotensive (supine, resting systolic blood pressure <140 mm Hg and diastolic blood pressure < 90 mm Hg.
• Normal supine, resting heart rate (< 90 per minute).
• Willing to duplicate their previous 24-hour diet, refrain from alcohol and caffeine for 24 hr prior to each trial, refrain from exercise 48 hr prior to each trial, refrain from any nutrients that might affect choline 24 hr prior to each trial, and fast for 8 hours prior to each trial.

Exclusion Criteria:

• Highly trained or competitive athletes.
• History of diabetes, asthma, gout, fibromyalgia or clinical diagnosis of IBS/IBD.
• History of malignancy in the previous 5 years except for non-melanoma skin cancer (basal cell cancer or squamous cell cancer of the skin).
• History of psychiatric disorder.
• History of hepatorenal, musculoskeletal, autoimmune, or neurologic disease.
• Use of any dietary supplements that may confound the study or its endpoints, including creatine, BCAA, HMB, betaine, beta-alanine, etc.
• Use of stimulants or anxiety or ADHD medication.
• Caffeine intake of three or more cups of coffee or equivalent (>400 mg) per day.
• Alcohol consumption (more than 2 standard alcoholic drinks per day or more than 10 drinks per week) or drug abuse or dependence.
• Smokers.
• Clinically significant abnormal laboratory results at screening.
• Prior gastrointestinal bypass surgery (Lapband, etc.).
• Other known gastrointestinal or metabolic diseases that might impact nutrient absorption or metabolism, e.g., short bowel syndrome, diarrheal illnesses, history of colon resection, gastro paresis, Inborn-Errors-of-Metabolism (such as PKU).
• Chronic inflammatory condition or disease (e.g., rheumatoid arthritis, Crohn's disease, ulcerative colitis, Lupus, HIV/AIDS, etc.).
• Concomitant use of corticosteroids or testosterone replacement therapy (ingestion, injection, or transdermal).
• Known allergy or sensitivity to any ingredient in the test formulations as listed in the Certificates-of-Analysis.
• Currently participating in another research study with an investigational product or have been in another research study in the past 30 days.
• Any other diseases or conditions that, in the opinion of the medical staff, could confound the primary endpoint or place the subject at increased risk of harm if they were to participate.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo	Dietary supplement: Placebo; Maltodextrin
Active Comparator: Low Dose Alpha-GPC; 315 mg dose of alpha-glycerylphosphorycholine (alpha-GPC)	Dietary supplement: 315 mg Alpha-GPC; 350 mg of 90% pure alpha-GPC (315 mg)
Active Comparator: High Dose Alpha-GPC; 630 mg dose of alpha-glycerylphosphorycholine (alpha-GPC)	Dietary supplement: 630 mg Alpha-GPC; 700 mg of 90% pure alpha-GPC (630 mg)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cognitive Performance-NBack	The N Back cognitive performance test (https://www.lumosity.com/app/v4/games/speed-match-overdrive-web )	Assessed 60 minutes after ingestion of assigned test product and approximately 3 hours after ingestion during visits 2, 3, and 4
Cognitive Performance	Flanker Cognitive Performance Test (https://www.psytoolkit.org/experiment-library/flanker.html)	Assessed 60 minutes after ingestion of assigned test product and approximately 3 hours after ingestion during visits 2, 3, and 4
Cognitive Performance	Stroop Color Matching Test	Assessed 60 minutes after ingestion of assigned test product and approximately 3 hours after ingestion during visits 2, 3, and 4

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Lower Body Power	Vertical Jump for Lower Body Power (Tendo)	Assessed 90 minutes post-ingestion during each study visit
Upper Body Power	Bench Press Throw for Upper Body Power (Tendo) @ 50%1RM	Assessed 90 minutes post-ingestion during each study visit
Growth Hormone	Serum Growth Hormone Concentrations	Assessed before exercise and 5, 15, 30, and 60 minutes after exercise during visits 2, 3, and 4
Perceived mood assessed using visual analog scale	Perceived mood assessed using the Visual Analog Scale (VAS), a 0-100 scale where 0 indicates 'worst mood imaginable' and 100 indicates 'best mood imaginable.' Higher scores represent better perceived mood.	Assessed 60 minutes after ingestion of assigned test product and approximately 3 hours after ingestion during visits 2, 3, and 4
Perceived motivation assessment using visual analog scales	Perceived motivation assessed using the Visual Analog Scale (VAS), with a range of 0-100 where 0 indicates 'no motivation' and 100 indicates 'maximum motivation.' Higher scores represent better perceived motivation.	Assessed 60 minutes after ingestion of assigned test product and approximately 3 hours after ingestion during visits 2, 3, and 4
Perceived Alertness Assessment Using Visual Analog Scale (VAS)	Perceived alertness assessed using the Visual Analog Scale (VAS), with a range of 0-100 where 0 indicates 'no alertness' and 100 indicates 'maximum alertness.' Higher scores represent better perceived alertness.	Assessed 60 minutes after ingestion of assigned test product and approximately 3 hours after ingestion during visits 2, 3, and 4
Perceived Concentration Assessment Using Visual Analog Scale (VAS)	Perceived concentration assessed using the Visual Analog Scale (VAS), with a range of 0-100 where 0 indicates 'no concentration' and 100 indicates 'maximum concentration.' Higher scores represent better perceived concentration.	Assessed 60 minutes after ingestion of assigned test product and approximately 3 hours after ingestion during visits 2, 3, and 4
Non-exertional Heart Rate Measurement	Heart rate measured in a non-exertional state using an automated sphygmomanometer.	Assessed 60 minutes after ingestion of assigned test product and approximately 3.5 hours after ingestion during visits 2, 3, and 4
Non-exertional Blood Pressure Measurement (Systolic and Diastolic)	Blood pressure measured in a non-exertional state using an automated sphygmomanometer. Both systolic and diastolic pressures will be assessed.	Assessed 60 minutes after ingestion of assigned test product and approximately 3.5 hours after ingestion during visits 2, 3, and 4

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent Body Fat	Percent body fat assessed using bioelectrical impedance analysis	At baseline (Visit 1), at the start of the study.
Dietary Intake	24-Hour Dietary Intake using 24-hour recall approach. Energy and macronutrient intake were evaluated.	Day 1, Day 8, and Day 15

Collaborators and Investigators

• Sponsor: Lindenwood University
• Collaborators: NNB Nutrition
• Investigators: Principal Investigator: Tim Ziegenfuss, PhD, Center for Applied Health Sciences

Study record dates

Study Major Dates

• Study Start (Actual): January 9, 2024
• Primary Completion (Actual): June 11, 2024
• Study Completion (Actual): June 11, 2024

Study Registration Dates

• First Submitted: November 12, 2024
• First Submitted That Met QC Criteria: November 13, 2024
• First Posted (Actual): November 15, 2024

Study Record Updates

• Last Update Posted (Actual): November 15, 2024
• Last Update Submitted That Met QC Criteria: November 13, 2024
• Last Verified: November 1, 2024

More Information

Terms related to this study

• Keywords: Performance; Cognition; Nootropic; Mental Acuity; Mental; Acute supplementation
• Other Study ID Numbers: NNB-001-012024

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: No plan to share IPD.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No