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Study · Not a test of the peptide alone · 2022

26 results

LGD-4033 and MK-677 use impacts body composition, circulating biomarkers, and skeletal muscle androgenic hormone and receptor content: A case report.

Cardaci TD, Machek SB, Wilburn DT, Heileson JL, Harris DR, Cintineo HP, Willoughby DS

Experimental physiology16 Nov 2022Cited by 9 (Europe PMC)

PMID36303408 (opens in a new tab)DOI10.1113/ep090741 (opens in a new tab)PepBankPUB-36303408
Publisher pagePubMedAsk about this study
Jump to 26 results

Summary

New findingsWhat is the main observation in this case? Co-administration of LGD-4033 and MK-677 increased body mass, lean mass and fat mass, while negatively impacting bone, serum lipids, liver enzymes, testosterone (total and free) and, probably, follicle-stimulating hormone. What insights does it reveal? Our cross-sectional data imply that these compounds might alter intramuscular androgenic hormone and receptor concentrations along with promoting muscular strength, when compared with previously published data from trained males.AbstractLGD-4033, a selective androgen receptor modulator, and MK-677, a growth hormone secretagogue, are being used increasingly amongst recreationally active demographics. However, limited data exist describing their effects on health- and androgen-related biomarkers. The purpose of this case study was to determine changes in body composition and biomarkers during and after continued co-administration of LGD-4033 and MK-677. We also aimed to examine muscular strength and intramuscular androgen-associated biomarkers relative to non-users. A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks. Blood and body composition metrics were obtained pre-, on- and post-cycle. One-repetition maximum leg and bench press, in addition to intramuscular androgens and androgen receptor content, were analysed on-cycle. We observed pre- to on-cycle changes in body composition (body mass, +6.0%; total lean body mass, +3.1%; trunk lean body mass, +6.6%; appendicular lean body mass, +4.3%; total fat mass, +15.4%; trunk fat mass, +2.8%; and appendicular fat mass, +14.8%), bone (bone mineral content, -3.60%; area, -1.1%; and bone mineral density, -2.1%), serum lipid-associated biomarkers (cholesterol, +14.8%; triglycerides, +39.2%; low-density lipoprotein-cholesterol, +40.0%; and high-density lipoprotein-cholesterol, -36.4%), liver-associated biomarkers (aspartate aminotransferase, +95.8%; and alanine aminotransferase, +205.0%) and androgen-associated biomarkers (free testosterone, -85.7%; total testosterone, -62.3%; and sex hormone-binding globulin, -79.6%); however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol. Follicle-stimulating hormone was below clinical reference values on- (1.2 IU/L) and post-cycle (1.3 IU/L). Intramuscular androgen receptor (-44.6%), testosterone (+47.8%) and dihydrotestosterone (+34.4%), in addition to one-repetition maximum leg press and bench press (+39.2 and +32.0%, respectively), were different in the case subject compared with non-users. These data demonstrate that LGD-4033 and MK-677 increase several body composition parameters, whilst negatively impacting bone and several serum biomarkers. Given the sparsity of data in recreationally using demographics, further research is warranted to elucidate the acute and chronic physiological effects of these anabolic agents.
CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study26

No result from this study comes from a test of the peptide.

Studies that did not test the peptide alone26

In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. These results are not evidence about taking MK-677 (ibutamoren).

  1. 01HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male, LGD-4033 plus MK‑677 increased body mass on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased body mass, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseBody mass
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Body weight · Metabolic and weight

    Measurements

    Body mass
    6%
    on-cycle

    Source sentences

    Summary
    body mass, +6.0%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  2. 02HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male, LGD-4033 plus MK‑677 increased total lean body mass on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased total lean mass, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseTotal lean body mass
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Body weight · Metabolic and weight

    Measurements

    Total lean body mass
    3.1%
    on-cycle

    Source sentences

    Summary
    total lean body mass, +3.1%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  3. 03HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male, LGD-4033 plus MK‑677 increased trunk lean body mass on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased trunk lean mass, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseTrunk lean body mass
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Body weight · Metabolic and weight

    Measurements

    Trunk lean body mass
    6.6%
    on-cycle

    Source sentences

    Summary
    trunk lean body mass, +6.6%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  4. 04HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male, LGD-4033 plus MK‑677 increased appendicular lean body mass on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased limb lean mass, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseAppendicular lean body mass
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Body weight · Metabolic and weight

    Measurements

    Appendicular lean body mass
    4.3%
    on-cycle

    Source sentences

    Summary
    appendicular lean body mass, +4.3%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  5. 05HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male, LGD-4033 plus MK‑677 increased total fat mass on-cycle, which did not return to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased total fat mass, which did not return to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseTotal fat mass
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Body weight · Metabolic and weight

    Measurements

    Total fat mass
    15.4%
    on-cycle

    Source sentences

    Summary
    total fat mass, +15.4%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  6. 06HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male, LGD-4033 plus MK‑677 increased trunk fat mass on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased trunk fat mass, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseTrunk fat mass
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Body weight · Metabolic and weight

    Measurements

    Trunk fat mass
    2.8%
    on-cycle

    Source sentences

    Summary
    trunk fat mass, +2.8%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  7. 07HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male, LGD-4033 plus MK‑677 increased appendicular fat mass on-cycle, which did not return to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased limb fat mass, which did not return to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseAppendicular fat mass
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Body weight · Metabolic and weight

    Measurements

    Appendicular fat mass
    14.8%
    on-cycle

    Source sentences

    Summary
    appendicular fat mass, +14.8%)
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  8. 08HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 reduced bone mineral content on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen reduced bone mineral content, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseBone mineral content
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Bone and joint · Musculoskeletal

    Measurements

    Bone mineral content
    −3.6%
    on-cycle

    Source sentences

    Summary
    bone mineral content, -3.60%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  9. 09HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 reduced bone area on-cycle, which did not return to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen reduced bone area, which did not return to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseBone area
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Bone and joint · Musculoskeletal

    Measurements

    Bone area
    −1.1%
    on-cycle

    Source sentences

    Summary
    bone (bone mineral content, -3.60%; area, -1.1%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  10. 10HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 reduced bone mineral density on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen reduced bone mineral density, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseBone mineral density
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Bone and joint · Musculoskeletal

    Measurements

    Bone mineral density
    −2.1%
    on-cycle

    Source sentences

    Summary
    bone mineral density, -2.1%)
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  11. 11HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 increased cholesterol on-cycle, which did not return to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased cholesterol, which did not return to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseTotal cholesterol
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Lipids · Metabolic and weight

    Measurements

    Total cholesterol
    14.8%
    on-cycle

    Source sentences

    Summary
    (cholesterol, +14.8%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  12. 12HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 increased triglycerides on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased triglycerides, which returned to their pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseTriglycerides
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Lipids · Metabolic and weight

    Measurements

    Triglycerides
    39.2%
    on-cycle

    Source sentences

    Summary
    triglycerides, +39.2%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  13. 13HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 increased LDL cholesterol on-cycle, which did not return to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased LDL cholesterol, which did not return to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseLDL cholesterol
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Lipids · Metabolic and weight

    Measurements

    LDL cholesterol
    40%
    on-cycle

    Source sentences

    Summary
    low-density lipoprotein-cholesterol, +40.0%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  14. 14HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 reduced HDL cholesterol on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen reduced HDL cholesterol, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseHDL cholesterol
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Lipids · Metabolic and weight

    Measurements

    HDL cholesterol
    −36.4%
    on-cycle

    Source sentences

    Summary
    high-density lipoprotein-cholesterol, -36.4%)
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  15. 15HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 increased aspartate aminotransferase on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased aspartate aminotransferase, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseAspartate aminotransferase
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Liver fat and liver function · Liver

    Measurements

    Aspartate aminotransferase
    95.8%
    on-cycle

    Source sentences

    Summary
    aspartate aminotransferase, +95.8%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  16. 16HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 increased alanine aminotransferase on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen increased alanine aminotransferase, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseAlanine aminotransferase
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Liver fat and liver function · Liver

    Measurements

    Alanine aminotransferase
    205%
    on-cycle

    Source sentences

    Summary
    alanine aminotransferase, +205.0%)
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  17. 17HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 reduced free testosterone on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen reduced free testosterone, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseFree testosterone
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Sex hormones and fertility · Endocrine and hormones

    Measurements

    Free testosterone
    −85.7%
    on-cycle

    Source sentences

    Summary
    free testosterone, -85.7%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  18. 18HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 reduced total testosterone on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen reduced total testosterone, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseTotal testosterone
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Sex hormones and fertility · Endocrine and hormones

    Measurements

    Total testosterone
    −62.3%
    on-cycle

    Source sentences

    Summary
    total testosterone, -62.3%;
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  19. 19HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male, LGD-4033 plus MK‑677 reduced sex hormone-binding globulin on-cycle, which returned to pre-cycle values post-cycle.

    In plain wordsIn one male, the combined regimen reduced sex hormone-binding globulin, which returned to its pre-cycle value.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseSex hormone-binding globulin
    Study

    n = 1

    Comparator
    pre-cycle
    Outcome group
    Sex hormones and fertility · Endocrine and hormones

    Measurements

    Sex hormone-binding globulin
    −79.6%
    on-cycle

    Source sentences

    Summary
    sex hormone-binding globulin, -79.6%)
    2 context sentences
    Summary · context
    however, all variables returned to pre-cycle values post-cycle, apart from total fat mass, appendicular fat mass, bone area, total cholesterol and low-density lipoprotein-cholesterol.
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  20. 20HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male using LGD-4033 plus MK‑677, on-cycle follicle-stimulating hormone was below clinical reference values at 1.2 IU/L.

    In plain wordsIn one male using the combined regimen, follicle-stimulating hormone was below clinical reference values during use.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseFollicle-stimulating hormone on-cycle
    Study

    n = 1

    Comparator
    clinical reference values
    Outcome group
    Sex hormones and fertility · Endocrine and hormones

    Measurements

    Follicle-stimulating hormone
    1.2 IU/L
    on-cycle

    Source sentences

    Summary
    Follicle-stimulating hormone was below clinical reference values on- (1.2 IU/L) and post-cycle (1.3 IU/L).
    1 context sentence
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  21. 21HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesSafety outcome

    In one male after LGD-4033 plus MK‑677 use, follicle-stimulating hormone was below clinical reference values at 1.3 IU/L.

    In plain wordsIn one male after the combined regimen, follicle-stimulating hormone remained below clinical reference values.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseFollicle-stimulating hormone post-cycle
    Study

    n = 1

    Comparator
    clinical reference values
    Outcome group
    Sex hormones and fertility · Endocrine and hormones

    Measurements

    Follicle-stimulating hormone
    1.3 IU/L
    post-cycle

    Source sentences

    Summary
    Follicle-stimulating hormone was below clinical reference values on- (1.2 IU/L) and post-cycle (1.3 IU/L).
    1 context sentence
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  22. 22HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male using LGD-4033 plus MK‑677, intramuscular androgen receptor content was lower than in non-users.

    In plain wordsIn one male using the combined regimen, muscle androgen receptor content was lower than in non-users.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    DecreaseIntramuscular androgen receptor
    Study

    n = 1

    Comparator
    non-users
    Outcome group
    Sex hormones and fertility · Musculoskeletal

    Measurements

    Intramuscular androgen receptor
    −44.6%
    relative to non-users

    Source sentences

    Summary
    Intramuscular androgen receptor (-44.6%), testosterone (+47.8%) and dihydrotestosterone (+34.4%), in addition to one-repetition maximum leg press and bench press (+39.2 and +32.0%, respectively), were different in the case subject compared with non-users.
    1 context sentence
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  23. 23HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male using LGD-4033 plus MK‑677, intramuscular testosterone was higher than in non-users.

    In plain wordsIn one male using the combined regimen, muscle testosterone was higher than in non-users.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseIntramuscular testosterone
    Study

    n = 1

    Comparator
    non-users
    Outcome group
    Sex hormones and fertility · Musculoskeletal

    Measurements

    Intramuscular testosterone
    47.8%
    relative to non-users

    Source sentences

    Summary
    Intramuscular androgen receptor (-44.6%), testosterone (+47.8%) and dihydrotestosterone (+34.4%), in addition to one-repetition maximum leg press and bench press (+39.2 and +32.0%, respectively), were different in the case subject compared with non-users.
    1 context sentence
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  24. 24HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male using LGD-4033 plus MK‑677, intramuscular dihydrotestosterone was higher than in non-users.

    In plain wordsIn one male using the combined regimen, muscle dihydrotestosterone was higher than in non-users.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseIntramuscular dihydrotestosterone
    Study

    n = 1

    Comparator
    non-users
    Outcome group
    Sex hormones and fertility · Musculoskeletal

    Measurements

    Intramuscular dihydrotestosterone
    34.4%
    relative to non-users

    Source sentences

    Summary
    Intramuscular androgen receptor (-44.6%), testosterone (+47.8%) and dihydrotestosterone (+34.4%), in addition to one-repetition maximum leg press and bench press (+39.2 and +32.0%, respectively), were different in the case subject compared with non-users.
    1 context sentence
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  25. 25HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male using LGD-4033 plus MK‑677, maximal leg press strength was higher than in non-users.

    In plain wordsIn one male using the combined regimen, leg press strength was higher than in non-users.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseLeg press strength
    Study

    n = 1

    Comparator
    non-users
    Outcome group
    Exercise and physical function · Musculoskeletal

    Measurements

    One-repetition maximum leg press
    39.2%
    relative to non-users

    Source sentences

    Summary
    Intramuscular androgen receptor (-44.6%), testosterone (+47.8%) and dihydrotestosterone (+34.4%), in addition to one-repetition maximum leg press and bench press (+39.2 and +32.0%, respectively), were different in the case subject compared with non-users.
    1 context sentence
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

  26. 26HumanNot a test of MK-677 (ibutamoren) aloneCase report or seriesEfficacy outcome

    In one male using LGD-4033 plus MK‑677, maximal bench press strength was higher than in non-users.

    In plain wordsIn one male using the combined regimen, bench press strength was higher than in non-users.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseBench press strength
    Study

    n = 1

    Comparator
    non-users
    Outcome group
    Exercise and physical function · Musculoskeletal

    Measurements

    One-repetition maximum bench press
    32%
    relative to non-users

    Source sentences

    Summary
    Intramuscular androgen receptor (-44.6%), testosterone (+47.8%) and dihydrotestosterone (+34.4%), in addition to one-repetition maximum leg press and bench press (+39.2 and +32.0%, respectively), were different in the case subject compared with non-users.
    1 context sentence
    Summary · context
    A 25-year-old male ingested LGD-4033 (10 mg) and MK-677 (15 mg) daily for 5 weeks.

    In this study, MK-677 (ibutamoren) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MK-677 (ibutamoren).

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    14 Oct 2026, 05:02 UTC

    Study results updated

  2. Version 1

    14 Oct 2026, 01:46 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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