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Completed

NCT Number: NCT05820399

Guayusa Extract on Exercise Training

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?

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Key information

Conditions

Desire to Exercise Exercise Training Physical Exertion

Age range

18 year–45 year

Sex eligibility

Female

Study type

Interventional

Phase

Not applicable

Primary location

Integrative Laboratory of Applied Physiology and Lifestyle Medicine

Iowa City, Iowa, 52242, United States

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

Organic Guayusa Extract

Dietary Supplement

Supplementation: Participants will supplement daily with organic guayusa extract, which 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) during 6 weeks of high intensity exercise training. Investigators and participants will be blinded to condition.

Placebo

Dietary Supplement

Participants will supplement daily with placebo (maltodextrin). Investigators and participants will be blinded to condition.

Primary outcomes

  1. Desire to Exercise

    Time frame: Throughout 6-week training period.

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

  2. Exercise Adherence

    Time frame: Throughout 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.

  3. Exercise Training Load

    Time frame: Throughout 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.

Secondary outcomes

  1. Desire to Exercise Secondary Measures

    Time frame: Throughout 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".

  2. Exercise Training Performance

    Time frame: Throughout 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.

  3. VO2peak

    Time frame: baseline, <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.

  4. Submaximal Exercise Fat Oxidation

    Time frame: baseline, <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.

  5. Submaximal Exercise Blood Pressure

    Time frame: baseline, <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.

  6. Fasting metabolic biomarkers

    Time frame: baseline, <7 days after completing the intervention

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

  7. Fasting total cholesterol

    Time frame: baseline, <7 days after completing the intervention

    Total cholesterol will be assessed from a fasting blood sample.

  8. Fasting HDL-cholesterol

    Time frame: baseline, <7 days after completing the intervention

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

  9. Fasting non-HDL cholesterol

    Time frame: baseline, <7 days after completing the intervention

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

  10. Fasting triglycerides

    Time frame: baseline, <7 days after completing the intervention

    Triglycerides will be assessed from a fasting blood sample

  11. Fasting Glucose

    Time frame: baseline, <7 days after completing the intervention

    Glucose will be assessed from a fasting blood sample

  12. Fasting insulin

    Time frame: baseline, <7 days after completing the intervention

    insulin will be assessed from a fasting blood sample

  13. Fasting c-peptide

    Time frame: baseline, <7 days after completing the intervention

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

  14. Fasting GLP-1

    Time frame: baseline, <7 days after completing the intervention

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

  15. Fasting GIP

    Time frame: baseline, <7 days after completing the intervention

    Fasting GIP will be assessed from a fasting blood sample

  16. Fasting IL-6

    Time frame: baseline, at 1 week during the intervention, <7 days after completing the intervention

    IL-6 will be assessed from a fasting blood sample

  17. Fasting IL-10

    Time frame: baseline, at 1 week during the intervention, <7 days after completing the intervention

    IL-10 will be assessed from a fasting blood sample

  18. Fasting TNFa

    Time frame: baseline, at 1 week during the intervention, <7 days after completing the intervention

    TNFa will be assessed from a fasting blood sample

  19. Fasting triiodothyronine (T3)

    Time frame: baseline, at 1 week during the intervention, <7 days after completing the intervention

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

  20. Fasting thyroxine (T4)

    Time frame: baseline, at 1 week during the intervention, <7 days after completing the intervention

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

  21. Fasting Progesterone

    Time frame: baseline, at 1 week during the intervention, <7 days after completing the intervention

    Progesterone will be assessed from a fasting blood sample

  22. Fasting Testosterone

    Time frame: baseline, at 1 week during the intervention, <7 days after completing the intervention

    Testosterone will be assessed from a fasting blood sample

  23. Fasting Estrogen

    Time frame: baseline, at 1 week during the intervention, <7 days after completing the intervention

    Estrogen will be assessed from a fasting blood sample

  24. Fasting Cortisol

    Time frame: baseline, at 1 week during the intervention, <7 days after completing the intervention

    Cortisol will be assessed from a fasting blood sample

  25. Fasting Adiponectin

    Time frame: baseline, <7 days after completing the intervention

    Adiponectin will be assessed from a fasting blood sample

  26. Fasting Leptin

    Time frame: baseline, <7 days after completing the intervention

    Leptin will be assessed from a fasting blood sample

  27. Fasting Adipsin

    Time frame: baseline, <7 days after completing the intervention

    Adipsin will be assessed from a fasting blood sample

  28. Fasting Lipocalin

    Time frame: baseline, <7 days after completing the intervention

    Lipocalin will be assessed from a fasting blood sample

  29. Fasting Plasminogen activator inhibitor-1 (PAI-1)

    Time frame: baseline, <7 days after completing the intervention

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

  30. Fasting Resistin

    Time frame: baseline, <7 days after completing the intervention

    Resistin will be assessed from a fasting blood sample

Other outcomes

  1. Rating of Perceived Exertion

    Time frame: Throughout 6-week training period.

    RPE will be assessed following each exercise session to determine subjective effort for each session on a scale of 1-10, where 1 is lowest perceived effort (e.g., rest) and 10 is greatest perceived effort.

Sponsors and collaborators

Lead sponsor

Nathaniel Jenkins

Other

Registry information

Official study title

Ability of Organic Guayusa Extract to Augment Desire to Train, Training Load, and Cardiometabolic Function in Physically Active Women Performing A High Intensity Exercise Training Program

Important dates

Study start
2022
Primary completion
2022
Study completion
2022
First posted
Apr 19, 2023
Registry last updated
Apr 19, 2023

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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