Caloric RestrictionPhase 4OPS IINCT04120363

Trial of Testosterone Undecanoate for Optimizing Performance During Military Operations

A Phase 4 study testing Testosterone Undecanoate and Sesame Oil in people with Caloric Restriction and Exercise, run by Pennington Biomedical Research Center at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

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Trial summary

The objective of this study is to determine the effects of a single dose of testosterone undecanoate during and in recovery from simulated operational stress. Read more about this study

Who is it for?: Ages 18 to 35 years, men onlyHealthy volunteers can take part
Conditions the study is for: Caloric Restriction, Exercise, Sleep
What is being tested?: Testosterone Undecanoate and Sesame Oil
Type of treatment: Injection or infusion
Could I receive a placebo?: Yes, some participants may receive a placebo
How many people: 34 participants
Where: 1 siteUnited States
Study dates: 23 Sep 2019to 8 Jul 2021
Phase: Phase 4
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 to 35 years
Men only
Healthy volunteers accepted
Adult

Who may be able to join

Men aged 18-35 years
Ability to understand verbal or written instructions/testing materials in English
Physically active (as determined by accelerometry and review of a physical activity log)
Not taking any prescription medications and/or willing to refrain from all medication use prior to and throughout the entire study period, unless provided/approved by the study physician
Willing to refrain from alcohol, smoking, e-cigarettes or use of any nicotine product, caffeine, and dietary supplement use throughout the entire study period
Willing to live on the Pennington Biomedical Research Center inpatient unit for 20 consecutive days
Meets age-specific US Army body composition standards according to Army Regulation 600-9, which includes estimates of percent body fat based on height, weight, and circumference measures (neck and waist)
Total testosterone concentration is within the normal physiological range (300-1,000 ng/dL)

Who cannot join

Musculoskeletal injuries that compromise exercise capability
Diagnosed cardiometabolic disorders (i.e., hypertension, hyperlipidemia, kidney disease, diabetes, etc.)
Allergies or intolerance to foods, vegetarian practices, or history of complications with lidocaine
Anabolic steroid, human growth hormone, or nutritional testosterone precursor-like supplement use within the past 6 months
Will not refrain from smoking (any nicotine product), alcohol, caffeine, or any other dietary supplement during the study
Adults unable to consent

Show all 16Show fewer

Women
Prisoners
Sedentary or engages in insufficient quantities of physical activity per week (aerobic and/or resistance training as determined by accelerometry and review of a physical activity log)
Exceeds age-specific US Army body composition standards according to Army Regulation 600-9
Previous history of kidney stones unless otherwise approved by the medical investigator
Systolic blood pressure > 150 or diastolic blood pressure > 95 mmHg
Previous history of breast or prostate cancer
Previous history of Chronic Obstructive Pulmonary Disease or Obstructive Sleep Apnea
Prostate-Specific Antigen (PSA) > 3ng/ml, Hematocrit > 50%, or positive urine drug screening
Based on the investigative team's clinical judgment, a subject may not be appropriate for participation in the study

Trial locations and contacts

1 site in 1 country.

United States1 site

Pennington Biomedical Research Center
Baton Rouge, Louisiana, 70808

Other trials in United States

About this study

Official title: A Randomized, Double-blind, Placebo Controlled Trial of Testosterone Undecanoate for Optimizing Physical and Cognitive Performance During Military Operations (OPS II)

The objective of this study is to determine the effects of a single dose of testosterone undecanoate during and in recovery from simulated operational stress.

Read the detailed description

This is a double-blind, randomized, placebo controlled trial in 32 physically active men exposed to 20 complete days (days 8-27) of simulated operational stress followed by 20 complete days of recovery (days 29-48). After completing baseline testing (Phase 1), participants will be randomized to receive either a single intramuscular injection of testosterone undecanoate or an isovolumetric placebo (Day 8). The 20-day simulated operational stress (Phase 2) will be highly controlled (live-in study) and consist of 4 successive cycles of undulating stress, starting with 2 consecutive days of low stress followed by 3 consecutive days of high stress. Low- and high-stress days will result from low and high militarily-relevant exercise-induced energy expenditures, adequate and restricted sleep (8 hours vs. 4 hours daily), and diet restriction to produce energy deficits. After completing Phase 2, participants will be released to resume their habitual physical activity routines and will be provided a controlled diet to consume (Phase 3), to assess recovery from sustained, severe operational stress.

Conditions: Caloric Restriction, Exercise, Sleep
Being tested: Testosterone Undecanoate, Sesame Oil
Keywords: testosterone, anabolism, muscle mass, military operational stress
Medical subject headings: Motor Activity

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Testosterone UndecanoateDrug
Also called Aveed
single intramuscular injection of 750 mg testosterone undecanoate
Sesame OilDrug
single intramuscular injection of 750 mg sesame oil solution

Study groups in NCT04120363
Study group	Role	What they receive
Placebo	Placebo comparator	single intramuscular injection of 750 mg sesame oil solution on Day 8 Receives: Drug: Sesame Oil
Testosterone	Experimental	single intramuscular injection of 750 mg testosterone undecanoate on Day 8 Receives: Drug: Testosterone Undecanoate

What is being measured

The primary outcome is the main question the study is designed to answer.

Load Carriage Time
A load carriage time trial (a militarily relevant aerobic performance assessment) was conducted near the end of each study phase to assess aerobic performance.
Measured: Day 5 (Phase 1), Day 26 (Phase 2), Day 47 (Phase 3)
Vertical Jump Height
Lower-body peak power was assessed near the end of each phase using a vertical jump test.
Measured: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3)
Total Mass Lifted
A 3-repetition maximum deadlift assessed muscular strength, endurance, and explosive power near the end of each study phase.
Measured: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3)
Wingate Peak Power
Anaerobic capacity was assessed using a Wingate anaerobic cycle test near the end of each study phase.
Measured: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3)
Peak Aerobic Capacity
Peak aerobic capacity was measured via treadmill VO2peak near the end of each study phase.
Measured: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3)

Secondary outcomes (1)

Body Composition
A four-compartment (4C) model factoring in body mass, body volume, total body water, and bone mineral content was used to calculate fat-free body mass and fat mass at the end of each study phase.
Measured: Day 7 (Phase 1), Day 28 (Phase 2), Day 49 (Phase 3)

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

23 Sep 20198 Jul 2021

First posted9 Oct 2019
Study start23 Sep 2019
Primary completion8 Jul 2021
Study completion8 Jul 2021

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Publications (4)Papers the sponsor has linked to this study.
Other trials for Caloric RestrictionStudies of the same condition, open and under way.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 4
Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Masking: Quadruple blind
Who is masked: Participant, Care provider, Investigator, Outcomes assessor
Enrolment: 34 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT04120363
Sponsor's protocol ID: PBRC 2019-017
Other IDs: W81XWH19C0162, W81XWH19D0010
Acronym: OPS II
Status last verified: Sep 2022
First submitted: 4 Oct 2019
Last updated: 7 Oct 2022
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No
Individual data sharing: No

Publications

Lowe AC, Niclou A, Varanoske AN, Harris MN, Hebert C, Johannsen NM, Heymsfield SB, Greenway FL, Margolis LM, Lieberman HR, Beyl RA, Ferrando AA, Pasiakos SM, Rood JC. Exercise Heart Rate Variability Suggests Parasympathetic Hyperactivity during Simulated Military Operations Irrespective of Testosterone Administration. Med Sci Sports Exerc. 2025 Sep 1;57(9):1979-1987. doi: 10.1249/MSS.0000000000003743. Epub 2025 Apr 25.
PubMed 40279652
Varanoske AN, Harris MN, Hebert C, Johannsen NM, Heymsfield SB, Greenway FL, Ferrando AA, Rood JC, Pasiakos SM. Bioelectrical impedance phase angle is associated with physical performance before but not after simulated multi-stressor military operations. Physiol Rep. 2023 Mar;11(6):e15649. doi: 10.14814/phy2.15649.
PubMed 36949577
Wong MC, Bennett JP, Leong LT, Tian IY, Liu YE, Kelly NN, McCarthy C, Wong JMW, Ebbeling CB, Ludwig DS, Irving BA, Scott MC, Stampley J, Davis B, Johannsen N, Matthews R, Vincellette C, Garber AK, Maskarinec G, Weiss E, Rood J, Varanoske AN, Pasiakos SM, Heymsfield SB, Shepherd JA. Monitoring body composition change for intervention studies with advancing 3D optical imaging technology in comparison to dual-energy X-ray absorptiometry. Am J Clin Nutr. 2023 Apr;117(4):802-813. doi: 10.1016/j.ajcnut.2023.02.006. Epub 2023 Feb 14.
PubMed 36796647
Varanoske AN, Harris MN, Hebert C, Howard EE, Johannsen NM, Heymsfield SB, Greenway FL, Margolis LM, Lieberman HR, Church DD, Ferrando AA, Rood JC, Pasiakos SM. Effects of testosterone undecanoate on performance during multi-stressor military operations: A trial protocol for the Optimizing Performance for Soldiers II study. Contemp Clin Trials Commun. 2021 Jul 3;23:100819. doi: 10.1016/j.conctc.2021.100819. eCollection 2021 Sep.
PubMed 34278044

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

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Study at a glance

From the registry record, last updated by the sponsor on 7 Oct 2022. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: A Randomized, Double-blind, Placebo Controlled Trial of Testosterone Undecanoate for Optimizing Physical and Cognitive Performance During Military Operations (OPS II)
ClinicalTrials.gov ID: NCT04120363
Acronym / sponsor ID: OPS II / PBRC 2019-017
Conditions: Caloric Restriction, Exercise, Sleep
Keywords: testosterone, anabolism, muscle mass, military operational stress
Phase: Phase 4
Study type: Interventional
Recruitment status: Completed
Enrolment: 34 participants (actual)
Lead sponsor: Pennington Biomedical Research CenterUniversity, hospital or other
Collaborators: United States Army Research Institute of Environmental Medicine, United States Department of Defense, University of Arkansas
Study start: 23 Sep 2019 (actual)
Primary completion: 8 Jul 2021 (actual)
Study completion: 8 Jul 2021 (actual)
First posted: 9 Oct 2019 (actual)
Results: Posted 7 Oct 2022

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

The objective of this study is to determine the effects of a single dose of testosterone undecanoate during and in recovery from simulated operational stress.

Detailed description

Study design

Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Masking: Quadruple blind (participant, care provider, investigator, outcomes assessor)
Number of arms: 2

Arm	Type	Receives
Placebo	Placebo comparator	Drug: Sesame Oilsingle intramuscular injection of 750 mg sesame oil solution on Day 8
Testosterone	Experimental	Drug: Testosterone Undecanoatesingle intramuscular injection of 750 mg testosterone undecanoate on Day 8

Who may qualify

Ages: 18 to 35 years
Sex: Male only
Healthy volunteers: Accepted
Age groups: Adult

Key inclusion criteria (8 listed)

Men aged 18-35 years
Ability to understand verbal or written instructions/testing materials in English
Physically active (as determined by accelerometry and review of a physical activity log)
Not taking any prescription medications and/or willing to refrain from all medication use prior to and throughout the entire study period, unless provided/approved by the study physician
Willing to refrain from alcohol, smoking, e-cigarettes or use of any nicotine product, caffeine, and dietary supplement use throughout the entire study period

Key exclusion criteria (16 listed)

Musculoskeletal injuries that compromise exercise capability
Diagnosed cardiometabolic disorders (i.e., hypertension, hyperlipidemia, kidney disease, diabetes, etc.)
Allergies or intolerance to foods, vegetarian practices, or history of complications with lidocaine
Anabolic steroid, human growth hormone, or nutritional testosterone precursor-like supplement use within the past 6 months
Will not refrain from smoking (any nicotine product), alcohol, caffeine, or any other dietary supplement during the study

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Testosterone UndecanoateAlso: Aveedsingle intramuscular injection of 750 mg testosterone undecanoate	Drug	Testosterone
Sesame Oilsingle intramuscular injection of 750 mg sesame oil solution	Drug	Placebo

Primary outcome

Load Carriage Time
Time frame: Day 5 (Phase 1), Day 26 (Phase 2), Day 47 (Phase 3)
A load carriage time trial (a militarily relevant aerobic performance assessment) was conducted near the end of each study phase to assess aerobic performance.
Vertical Jump Height
Time frame: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3)
Lower-body peak power was assessed near the end of each phase using a vertical jump test.
Total Mass Lifted
Time frame: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3)
A 3-repetition maximum deadlift assessed muscular strength, endurance, and explosive power near the end of each study phase.
Wingate Peak Power
Time frame: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3)
Anaerobic capacity was assessed using a Wingate anaerobic cycle test near the end of each study phase.
Peak Aerobic Capacity
Time frame: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3)
Peak aerobic capacity was measured via treadmill VO2peak near the end of each study phase.

1 secondary outcome

Body Composition
Time frame: Day 7 (Phase 1), Day 28 (Phase 2), Day 49 (Phase 3)

Results and safety

Results posted to the registry on 7 Oct 2022, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
Testosterone	16	16
Placebo	18	18

Primary outcome: Load Carriage Time

Time frame: Day 5 (Phase 1), Day 26 (Phase 2), Day 47 (Phase 3). Least squares mean (Standard Error). Unit: min

Measure	Testosterone n = 16	Placebo n = 18
2.5 mile time, Phase 1	45.21 (2.01)	41.58 (1.94)
2.5 mile time, Phase 2	50.95 (2.01)	47.15 (1.99)
2.5 mile time, Phase 3	44.31 (2.07)	39.34 (2.12)

Population analysed: 2 participants in the placebo group dropped out of the study during Phase 2

Primary outcome: Vertical Jump Height

Time frame: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3). Least squares mean (Standard Error). Unit: cm

Measure	Testosterone n = 16	Placebo n = 18
Vertical Jump Height, Phase 1	54.5 (2.5)	53.6 (2.4)
Vertical Jump Height, Phase 2	49.1 (2.5)	50.0 (2.5)
Vertical Jump Height, Phase 3	54.0 (2.5)	50.5 (2.5)

Population analysed: 2 participants in the placebo group dropped out of the study during Phase 2

Primary outcome: Total Mass Lifted

Time frame: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3). Least squares mean (Standard Error). Unit: kg

Measure	Testosterone n = 16	Placebo n = 18
Total Mass Lifted, Phase 1	127.4 (7.4)	127.9 (7.0)
Total Mass Lifted, Phase 2	122.7 (7.4)	119.0 (7.2)
Total Mass Lifted, Phase 3	126.7 (7.7)	129.8 (7.2)

Population analysed: 2 participants in the placebo group dropped out of the study during Phase 2

Primary outcome: Wingate Peak Power

Time frame: Day 4 (Phase 1), Day 25 (Phase 2), Day 46 (Phase 3). Least squares mean (Standard Error). Unit: W

Measure	Testosterone n = 16	Placebo n = 18
Wingate peak power, absolute, Phase 1	879.4 (49.6)	837.8 (49.6)
Wingate peak power, absolute, Phase 2	753.8 (49.6)	736.0 (49.6)
Wingate peak power, absolute, Phase 3	821.8 (49.6)	790.8 (49.6)

Population analysed: 2 participants in the placebo group dropped out of the study during Phase 2

1 secondary outcome is reported in the full results.

Adverse events

Time frame: Adverse event data was collected from the time of the screening visit until study completion, up to 4 months.. Other adverse events reported at 0% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
Testosterone	0 of 16 (0%)	15 of 16 (93.8%)	0 of 16
Placebo	0 of 18 (0%)	16 of 18 (88.9%)	0 of 18

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 7 Oct 2022.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
Derived from this study: PubMed 40279652Lowe AC, Niclou A, Varanoske AN, Harris MN, Hebert C, Johannsen NM, Heymsfield SB, Greenway FL, Margolis LM, Lieberman HR, Beyl RA, Ferrando AA, Pasiakos SM, Rood JC. Exercise Heart Rate Variability Suggests Parasympathetic Hyperactivity during Simulated Military Operations Irrespective of Testosterone Administration. Med Sci Sports Exerc. 2025 Sep 1;57(9):1979-1987. doi: 10.1249/MSS.0000000000003743. Epub 2025 Apr 25.
Derived from this study: PubMed 36949577Varanoske AN, Harris MN, Hebert C, Johannsen NM, Heymsfield SB, Greenway FL, Ferrando AA, Rood JC, Pasiakos SM. Bioelectrical impedance phase angle is associated with physical performance before but not after simulated multi-stressor military operations. Physiol Rep. 2023 Mar;11(6):e15649. doi: 10.14814/phy2.15649.
Derived from this study: PubMed 36796647Wong MC, Bennett JP, Leong LT, Tian IY, Liu YE, Kelly NN, McCarthy C, Wong JMW, Ebbeling CB, Ludwig DS, Irving BA, Scott MC, Stampley J, Davis B, Johannsen N, Matthews R, Vincellette C, Garber AK, Maskarinec G, Weiss E, Rood J, Varanoske AN, Pasiakos SM, Heymsfield SB, Shepherd JA. Monitoring body composition change for intervention studies with advancing 3D optical imaging technology in comparison to dual-energy X-ray absorptiometry. Am J Clin Nutr. 2023 Apr;117(4):802-813. doi: 10.1016/j.ajcnut.2023.02.006. Epub 2023 Feb 14.
Derived from this study: PubMed 34278044Varanoske AN, Harris MN, Hebert C, Howard EE, Johannsen NM, Heymsfield SB, Greenway FL, Margolis LM, Lieberman HR, Church DD, Ferrando AA, Rood JC, Pasiakos SM. Effects of testosterone undecanoate on performance during multi-stressor military operations: A trial protocol for the Optimizing Performance for Soldiers II study. Contemp Clin Trials Commun. 2021 Jul 3;23:100819. doi: 10.1016/j.conctc.2021.100819. eCollection 2021 Sep.
Individual participant dataSharing planned: No

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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Jennifer C Rood, PhD principal investigator

Pennington Biomedical Research Center

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 4 study testing Testosterone Undecanoate and Sesame Oil in people with Caloric Restriction and Exercise, run by Pennington Biomedical Research Center at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 8 inclusion and 16 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 7 Oct 2022. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 7 Oct 2022). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Load Carriage Time (time frame: Day 5 (Phase 1), Day 26 (Phase 2), Day 47 (Phase 3)). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04120363, which also lists 4 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 7 Oct 2022.