Study analysis · Journal of the International Society of Sports Nutrition · 2025
This $50 supplement doesn't make you stronger—but it might make your quads bigger than creatine alone.
A fancy supplement with blueberry extract and citrate made one thigh muscle slightly bigger than a sugar pill, but not bigger than plain creatine—and it didn’t help strength at all.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
In simple terms
This study gave different supplements to guys who were lifting weights and saw that one mix made one leg muscle a tiny bit bigger than nothing at all. But it didn’t make them stronger or make other muscles bigger — and it wasn’t better than regular creatine. So it’s like saying a new flavor of cereal might make your bowl a little fuller, but not tastier or more filling than the old one.
What’s the bottom line?
Men took one of three supplements while doing leg exercises for 8 weeks: a mix of citrate, creatine, leucine, and blueberry extract; plain creatine; or a sugar pill.
How strong is this study?
This study did a good job by randomly giving out supplements and not telling anyone which one they got — that helps make sure the results aren’t biased. But it only had a few guys, so we can’t be super sure the results would be the same for everyone else. It’s like testing a new snack on three friends — it might work for them, but we don’t know if it’ll work for your whole school.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
78 / 100
- Randomization+20/20
- Blinding+15/15
- Control group+15/15
- Sample size (n=28)+2.6/20
- Follow-up+10/10
100 / 100
23 / 100
- P-values+15/15
- Effect sizeno effect size reported
- Confidence intervalsno confidence intervals
- Pre-registrationnot pre-registered
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 553 / 100
Probability of being correct
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
This design can establish causation. This study uses randomization and blinding, which allows for causal inference between the supplement and observed changes in muscle size. However, the small sample size and narrow population (young, recreationally active men) limit the strength and generalizability of causal claims.
Major COI
Major conflicts that significantly reduce study credibility
Two authors are employed by Phenolics LLC, the company that likely developed the supplement (TCLB) being tested, and the study shows favorable results for the blend, raising concerns about industry influence.
Funders
Conflict Details
Phenolics LLC: Employed by Phenolics LLC, the company associated with the supplement being tested
Phenolics LLC: Employed by Phenolics LLC, the company associated with the supplement being tested
Although no formal funding statement or COI disclosure is provided, the employment of two authors by Phenolics LLC — the entity likely responsible for the supplement — creates a significant conflict of interest. The study's positive findings for the TCLB blend, particularly in muscle size outcomes, may be influenced by industry affiliation. No safeguards for independent analysis are mentioned.
Key takeaways
- 01
The fancy mix made the deep thigh muscle (vastus intermedius) 5.4% bigger and total quads 3.9% bigger than the sugar pill.
- 02
Creatine alone did the same for a different thigh muscle.
- 03
Neither helped strength or endurance.
- 04
The muscle growth was small but meaningful for some people — 40% of those taking the fancy mix or creatine saw muscle gains big enough to matter in real life, while none in the placebo group did.
Surprising findings
- Creatine alone increased the vastus lateralis muscle size enough for 40% of users to exceed the minimal important difference, even though total quadriceps growth wasn’t statistically significant.Most people think creatine only boosts strength and water retention—but here, it triggered noticeable muscle growth in a specific muscle without changing overall size significantly.
- TCLB’s advantage was isolated to the vastus intermedius—a deep, hard-to-target muscle—not the more visible vastus lateralis.People expect supplements to bulk up the outer thigh (VL), but TCLB’s effect was on the hidden VI muscle, making it a stealthy growth that’s not visible in the mirror.
Practical takeaways
Stick with plain creatine monohydrate (5g/day) for muscle growth—it’s cheaper, proven, and just as effective as expensive blends.
This study only tested leg extensions in young men; results may not apply to women, older adults, or other exercises like squats or deadlifts.
medium confidenceIf you want visible muscle growth, focus on consistent training—supplements like creatine can help 40% of people reach a 'noticeable' gain, but they’re not magic.
No supplement improved strength or endurance—so don’t expect performance boosts.
medium confidenceWhy this study matters
TCLB vs. Creatine: The Muscle Growth Tie
The TCLB supplement (trisodium citrate, creatine, leucine, blueberry extract) increased the vastus intermedius muscle by 5.4% and total quadriceps by 3.9% compared to placebo—but creatine monohydrate alone achieved the same muscle growth without the extra ingredients.
Most people think fancy blends with superfoods like blueberry extract are superior—but this study shows plain creatine works just as well for muscle size, saving you money and avoiding marketing hype.
No Strength Gains—Despite Bigger Muscles
Neither TCLB nor creatine improved leg extension strength (1RM) or endurance (reps-to-failure), even though muscle size increased. This challenges the assumption that bigger muscles always mean stronger muscles.
You can build visible muscle without getting stronger—meaning muscle growth and strength aren’t always linked, especially with short-term supplementation.
40% Hit the 'Minimal Important Difference'
40% of people taking TCLB or creatine exceeded the minimal important difference (MID) in muscle size—meaning their gains were noticeable in real life—while 0% in the placebo group did.
This isn’t just statistical noise: for nearly half the participants, the supplement made a tangible, visible difference in muscle size—something fitness enthusiasts care about deeply.
Want the whole report?
Detailed mode opens the full scientific breakdown — every score component, the methodology, conflicts of interest, the evidence analysis behind each claim, and the raw study data.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Men took one of three supplements while doing leg exercises for 8 weeks: a mix of citrate, creatine, leucine, and blueberry extract; plain creatine; or a sugar pill.
Research results
The fancy mix made the deep thigh muscle (vastus intermedius) 5.4% bigger and total quads 3.9% bigger than the sugar pill. Creatine alone did the same for a different thigh muscle. Neither helped strength or endurance.
What this means - more context
The muscle growth was small but meaningful for some people — 40% of those taking the fancy mix or creatine saw muscle gains big enough to matter in real life, while none in the placebo group did.
This study tested whether a supplement blend (TCLB) enhances muscle growth or strength more than creatine monohydrate or placebo during 8 weeks of leg extension training in young men.
TCLB increased vastus intermedius and total quadriceps muscle size compared to placebo, but not more than creatine alone. Neither TCLB nor creatine improved strength or endurance. Only TCLB and creatine increased the proportion of individuals exceeding the minimal important difference in muscle size.
Methods Used
Randomized, double-blind trial with 28 recreationally active young men assigned to TCLB (n=10), creatine monohydrate (n=10), or placebo (n=8). All groups performed 8 weeks of leg extension resistance training. Muscle cross-sectional area (CSA) of quadriceps muscles, strength (1RM), and endurance (reps-to-failure) were measured before and after.
Main Finding
TCLB increased vastus intermedius CSA by 5.4% (33.37 vs. 31.64 cm²) and total quadriceps CSA by 3.9% (99.09 vs. 95.37 cm²) vs. placebo (p<0.005), but showed no significant advantage over creatine monohydrate. Neither supplement improved strength or endurance.
Confidence Level
High. Randomized, double-blind, placebo-controlled design with pre-post measurements, ANCOVA-adjusted analysis, and clear statistical reporting. Small sample size is a limitation but methodology is robust.
Study Flags
Red Flags
- •Small sample size (n=28 total)
- •No confidence intervals or effect sizes reported for most outcomes
- •Industry-affiliated authors (Phenolics LLC) may introduce bias
Surprising Findings
Creatine alone increased the vastus lateralis muscle size enough for 40% of users to exceed the minimal important difference, even though total quadriceps growth wasn’t statistically significant.
Most people think creatine only boosts strength and water retention—but here, it triggered noticeable muscle growth in a specific muscle without changing overall size significantly.
Practical Takeaways
Stick with plain creatine monohydrate (5g/day) for muscle growth—it’s cheaper, proven, and just as effective as expensive blends.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 553 / 100
Probability of being correct
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Human RCT
Subject
Moderate probability
on the GRADE evidence scale
This study gave different supplements to guys who were lifting weights and saw that one mix made one leg muscle a tiny bit bigger than nothing at all. But it didn’t make them stronger or make other muscles bigger — and it wasn’t better than regular creatine. So it’s like saying a new flavor of cereal might make your bowl a little fuller, but not tastier or more filling than the old one.
Major conflicts — industry funding with significant control over the research. Reporting score and overall score cap have been reduced.
Strengths
- Randomized and double-blinded design
- Placebo-controlled with two active comparison groups
- Pre- and post-training measurements with ANCOVA adjustment
Weaknesses
- Small sample size (n=28 total, n=8 in placebo group)
- Limited demographic diversity (only young men)
- Only one type of exercise (leg extension) was studied
Methodology
Evidence Keywords
Statistical Reporting
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Men took one of three supplements while doing leg exercises for 8 weeks: a mix of citrate, creatine, leucine, and blueberry extract; plain creatine; or a sugar pill.
Research results
The fancy mix made the deep thigh muscle (vastus intermedius) 5.4% bigger and total quads 3.9% bigger than the sugar pill. Creatine alone did the same for a different thigh muscle. Neither helped strength or endurance.
What this means - more context
The muscle growth was small but meaningful for some people — 40% of those taking the fancy mix or creatine saw muscle gains big enough to matter in real life, while none in the placebo group did.
This study tested whether a supplement blend (TCLB) enhances muscle growth or strength more than creatine monohydrate or placebo during 8 weeks of leg extension training in young men.
TCLB increased vastus intermedius and total quadriceps muscle size compared to placebo, but not more than creatine alone. Neither TCLB nor creatine improved strength or endurance. Only TCLB and creatine increased the proportion of individuals exceeding the minimal important difference in muscle size.
Methods Used
Randomized, double-blind trial with 28 recreationally active young men assigned to TCLB (n=10), creatine monohydrate (n=10), or placebo (n=8). All groups performed 8 weeks of leg extension resistance training. Muscle cross-sectional area (CSA) of quadriceps muscles, strength (1RM), and endurance (reps-to-failure) were measured before and after.
Main Finding
TCLB increased vastus intermedius CSA by 5.4% (33.37 vs. 31.64 cm²) and total quadriceps CSA by 3.9% (99.09 vs. 95.37 cm²) vs. placebo (p<0.005), but showed no significant advantage over creatine monohydrate. Neither supplement improved strength or endurance.
Confidence Level
High. Randomized, double-blind, placebo-controlled design with pre-post measurements, ANCOVA-adjusted analysis, and clear statistical reporting. Small sample size is a limitation but methodology is robust.
Study Flags
Red Flags
- •Small sample size (n=28 total)
- •No confidence intervals or effect sizes reported for most outcomes
- •Industry-affiliated authors (Phenolics LLC) may introduce bias
Surprising Findings
Creatine alone increased the vastus lateralis muscle size enough for 40% of users to exceed the minimal important difference, even though total quadriceps growth wasn’t statistically significant.
Most people think creatine only boosts strength and water retention—but here, it triggered noticeable muscle growth in a specific muscle without changing overall size significantly.
Practical Takeaways
Stick with plain creatine monohydrate (5g/day) for muscle growth—it’s cheaper, proven, and just as effective as expensive blends.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 553 / 100
Probability of being correct
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Human RCT
Subject
Moderate probability
on the GRADE evidence scale
This study gave different supplements to guys who were lifting weights and saw that one mix made one leg muscle a tiny bit bigger than nothing at all. But it didn’t make them stronger or make other muscles bigger — and it wasn’t better than regular creatine. So it’s like saying a new flavor of cereal might make your bowl a little fuller, but not tastier or more filling than the old one.
Major conflicts — industry funding with significant control over the research. Reporting score and overall score cap have been reduced.
Strengths
- Randomized and double-blinded design
- Placebo-controlled with two active comparison groups
- Pre- and post-training measurements with ANCOVA adjustment
Weaknesses
- Small sample size (n=28 total, n=8 in placebo group)
- Limited demographic diversity (only young men)
- Only one type of exercise (leg extension) was studied
Methodology
Evidence Keywords
Statistical Reporting
Scoring
How strong is this study?
This study did a good job by randomly giving out supplements and not telling anyone which one they got — that helps make sure the results aren’t biased. But it only had a few guys, so we can’t be super sure the results would be the same for everyone else. It’s like testing a new snack on three friends — it might work for them, but we don’t know if it’ll work for your whole school.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
78 / 100
- Randomization+20/20
- Blinding+15/15
- Control group+15/15
- Sample size (n=28)+2.6/20
- Follow-up+10/10
100 / 100
23 / 100
- P-values+15/15
- Effect sizeno effect size reported
- Confidence intervalsno confidence intervals
- Pre-registrationnot pre-registered
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 553 / 100
Probability of being correct
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
This design can establish causation. This study uses randomization and blinding, which allows for causal inference between the supplement and observed changes in muscle size. However, the small sample size and narrow population (young, recreationally active men) limit the strength and generalizability of causal claims.
Major COI
Major conflicts that significantly reduce study credibility
Two authors are employed by Phenolics LLC, the company that likely developed the supplement (TCLB) being tested, and the study shows favorable results for the blend, raising concerns about industry influence.
Funders
Conflict Details
Phenolics LLC: Employed by Phenolics LLC, the company associated with the supplement being tested
Phenolics LLC: Employed by Phenolics LLC, the company associated with the supplement being tested
Although no formal funding statement or COI disclosure is provided, the employment of two authors by Phenolics LLC — the entity likely responsible for the supplement — creates a significant conflict of interest. The study's positive findings for the TCLB blend, particularly in muscle size outcomes, may be influenced by industry affiliation. No safeguards for independent analysis are mentioned.
Standing
The people behind it
The researchers who wrote the study this analysis is built on.
Authored by
8 researchersIf this is your work, this is how we attribute it on Fit Body Science. Trevor D. Roberts is listed as the lead author.