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Guayusa Extract on Exercise Training

Not Applicable
Completed
Conditions
Desire to Exercise
Exercise Training
Physical Exertion
Interventions
Dietary Supplement: Organic Guayusa Extract
Dietary Supplement: Placebo
Registration Number
NCT05820399
Lead Sponsor
Nathaniel Jenkins
Brief Summary

Guayusa extract is a caffeinated Amazonian 'super-leaf' belonging to the holly species that contains a very unique blend of polyphenol antioxidants and caffeine (\~20% caffeine, 30% chlorogenic acids, 5% catechins). It is also remarkably low in tannins which are responsible for the bitter taste found in most teas - giving it a sweet flavor profile. As such, it is marketed as an ingredient that can help support energy and performance with potential health-related benefits due to its antioxidant properties. Indeed, ingredients such as these are often consumed by individuals prior to exercise in order to help improve exercise performance, or otherwise to support health-related goals. Whereas several studies have suggested that caffeine and chlorogenic acid consumption may improve performance, mood, and concentration, and some evidence in animals have linked catechin consumption to improved health outcomes, no studies have previous studied whether guayusa extract supplementation helps to support exercise performance in humans. In this study, we will test the whether dietary supplementation with the botanical organic guayusa extract helps support (1) the desire to exercise and exercise performance throughout a 6-week high intensity exercise training program, and thus (2) helps support the physiological adaptations (including body composition, fasting metabolic biomarkers, blood pressure and heart rate, submaximal and maximal exercise performance and fuel metabolism, and changes in the gut microbiome/mycobiome) to a 6-week high intensity exercise training program.

Question 1: Does organic guayusa extract supplementation support the desire to train and training load in physically-active women performing a high-intensity exercise training program?

Question 2: Does organic guayusa extract supplementation support physiological adaptation to exercise (including body composition, fasting metabolic biomarkers, blood pressure and heart rate, submaximal and maximal exercise performance and fuel metabolism, and changes in the gut microbiome/mycobiome) in physically-active women performing a high-intensity exercise training program?

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
57
Inclusion Criteria
  • Females
  • 18-45 years, inclusive
  • Physically active >=150 min/wk Moderate Intensity or >=75 min/wk Vigorous Intensity PA) for >=3 months
  • BMI < 35 kg/m2
  • Otherwise healthy and ready to participate in an exercise program as indicated by responses on the 2021 Physical Activity Readiness Questionnaire Plus (PAR-Q+)
  • Habitual caffeine consumption <=200 mg/day OR 2-week washout of current caffeine usage prior to participation
  • No current dietary supplementation OR 2-week washout of current supplement usage prior to participation
Exclusion Criteria
  • Current injury or illness that precludes exercise participation
  • Current nicotine or cannabis use
  • Use of prescription ADD/ADHD, anti-depressant, or other central acting medication, or previously diagnosed ADD/ADHD, clinically depressed, or generalized anxiety disorder
  • Current taking prescription stimulants (i.e., Adderall, Ritalin, Vyvanse, etc.)
  • Participants with a history of metabolic, hepatorenal, musculoskeletal, autoimmune, or neurologic disease; or currently taking thyroid, hormonal, hyperlipidemic, hypoglycemic, anti-hypertensive, anti-inflammatory, or anti-coagulant medications.
  • Treated for Metabolic Syndrome or having been clinically diagnosed with, or taking medication for a cardiometabolic-disorder (e.g., Pre-diabetes, Type II diabetes, high blood pressure, obesity, hypercholesterolemia, etc.)
  • Currently pregnant or lactating
  • Diagnosed allergy to any ingredient present within the study treatments
  • Current competitive NCAA athlete
  • Inability or unwillingness to comply with the controls and conditions of the study

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Organic Guayusa Extract + High Intensity ExerciseOrganic Guayusa ExtractParticipants will consume an organic guayusa extract supplement that contains caffeine and antioxidants each day for 6 weeks while completing the exercise training program on 3 days/week. On days that participants exercise, they will consume the supplement 30-60 minutes before exercise training. On days they do not exercise, they will consume the capsules upon waking.
Placebo + High Intensity ExercisePlaceboParticipants will consume a placebo consisting of maltodextrin each day for 6 weeks while completing the exercise training program. The placebo will be provided in capsule identical in appearance to the active supplement. On days that participants exercise, they will consume the placebo 30-60 minutes before exercise training. On days they do not exercise, they will consume the capsules upon waking.
Primary Outcome Measures
NameTimeMethod
Exercise Training LoadThroughout 6-week training period.

Resistance Exercise Training Volume (normalized to bodyweight) will be quantified in each resistance training workout (2x/week) and used as a quantitative indicator of exercise performance/effort.

Desire to ExerciseThroughout 6-week training period.

Desire to Exercise will be assessed Primarily via the Assessment of Exercise Readiness using a 41-item Exercise Readiness Questionnaire.

Exercise AdherenceThroughout 6-week training period.

Exercise training session adherence will be assessed across all exercise training sessions as a primary quantitative indicator of desire to exercise. Adherence will be assessed as the actual number of completed exercise sessions among participants in each group relative (i.e., percent, %) to the number of total planned exercise sessions. Group differences in session adherence will be compared by chi squared tests.

Secondary Outcome Measures
NameTimeMethod
Fasting Progesteronebaseline, at 1 week during the intervention, <7 days after completing the intervention

Progesterone will be assessed from a fasting blood sample

VO2peakbaseline, <7 days after completing the intervention

VO2peak will be assessed during a ramp test on a electronically-braked cycle ergometer performed to volitional exhaustion with pulmonary gas exchange analysis.

Submaximal Exercise Fat Oxidationbaseline, <7 days after completing the intervention

Submaximal Exercise Fat Oxidation (%) will be assessed during exercise at a fixed power (i.e., 75W) on an electronically-braked cycle ergometer with pulmonary gas exchange analysis.

Fasting total cholesterolbaseline, <7 days after completing the intervention

Total cholesterol will be assessed from a fasting blood sample.

Fasting triiodothyronine (T3)baseline, at 1 week during the intervention, <7 days after completing the intervention

Triiodothyronine (T3) will be assessed from a fasting blood sample

Fasting Estrogenbaseline, at 1 week during the intervention, <7 days after completing the intervention

Estrogen will be assessed from a fasting blood sample

Fasting Adipsinbaseline, <7 days after completing the intervention

Adipsin will be assessed from a fasting blood sample

Fasting Plasminogen activator inhibitor-1 (PAI-1)baseline, <7 days after completing the intervention

Plasminogen activator inhibitor-1 (PAI-1) will be assessed from a fasting blood sample

Fasting HDL-cholesterolbaseline, <7 days after completing the intervention

HDL-cholesterol will be assessed from a fasting blood sample.

Fasting Glucosebaseline, <7 days after completing the intervention

Glucose will be assessed from a fasting blood sample

Fasting insulinbaseline, <7 days after completing the intervention

insulin will be assessed from a fasting blood sample

Fasting Resistinbaseline, <7 days after completing the intervention

Resistin will be assessed from a fasting blood sample

Desire to Exercise Secondary MeasuresThroughout 6-week training period.

Secondary assessments of Desire to Exercise will include visual analog scales (range 0 - 50, with 0 indicating lower desire and 50 indicating higher desire) used to assess readiness immediately before exercise sessions to "exercise right now", to "invest physical energy right now" and to "invest mental energy right now".

Fasting non-HDL cholesterolbaseline, <7 days after completing the intervention

Non-HDL cholesterol will be assessed from a fasting blood sample.

Fasting GLP-1baseline, <7 days after completing the intervention

Fasting GLP-1 will be assessed from a fasting blood sample

Fasting IL-10baseline, at 1 week during the intervention, <7 days after completing the intervention

IL-10 will be assessed from a fasting blood sample

Fasting thyroxine (T4)baseline, at 1 week during the intervention, <7 days after completing the intervention

Thyroxine (T4) will be assessed from a fasting blood sample

Fasting Testosteronebaseline, at 1 week during the intervention, <7 days after completing the intervention

Testosterone will be assessed from a fasting blood sample

Fasting Cortisolbaseline, at 1 week during the intervention, <7 days after completing the intervention

Cortisol will be assessed from a fasting blood sample

Fasting Adiponectinbaseline, <7 days after completing the intervention

Adiponectin will be assessed from a fasting blood sample

Exercise Training PerformanceThroughout 6-week training period.

Secondary assessments of exercise training performance will include performance during a) a weekly airbike interval exercise session (Avg W), b) a weekly 500 m row (time to completion, Avg W), and c) the time (min) taken to complete the weekly metabolic conditioning workout.

Submaximal Exercise Blood Pressurebaseline, <7 days after completing the intervention

Submaximal Systolic and Diastolic Exercise Blood Pressure (mmHg) will be assessed during exercise at a fixed power (75W) on an electronically-braked cycle ergometer.

Fasting metabolic biomarkersbaseline, <7 days after completing the intervention

Total cholesterol, HDL-cholesterol, LDL-cholesterol, non-HDL cholesterol, triglycerides, glucose, insulin, c-peptide, GLP-1, GIP

Fasting triglyceridesbaseline, <7 days after completing the intervention

Triglycerides will be assessed from a fasting blood sample

Fasting c-peptidebaseline, <7 days after completing the intervention

Fasting c-peptide will be assessed from a fasting blood sample

Fasting GIPbaseline, <7 days after completing the intervention

Fasting GIP will be assessed from a fasting blood sample

Fasting IL-6baseline, at 1 week during the intervention, <7 days after completing the intervention

IL-6 will be assessed from a fasting blood sample

Fasting TNFabaseline, at 1 week during the intervention, <7 days after completing the intervention

TNFa will be assessed from a fasting blood sample

Fasting Leptinbaseline, <7 days after completing the intervention

Leptin will be assessed from a fasting blood sample

Fasting Lipocalinbaseline, <7 days after completing the intervention

Lipocalin will be assessed from a fasting blood sample

Trial Locations

Locations (1)

Integrative Laboratory of Applied Physiology and Lifestyle Medicine

🇺🇸

Iowa City, Iowa, United States

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