View

The Study

Acute influence of mixed creatine hydrochloride and caffeine supplementation on serum levels of testosterone and cortisol, repetition sustainability and resistance exercise volume

In simple terms

This study watched what happened when 12 athletes took different supplements before working out. It saw that one combo made them do a few more reps, but it didn't prove the supplements caused that — maybe they just felt luckier that day. So we can only say the supplement and the extra reps happened together, not that one made the other happen.

39%

Analysis score

39/ 90

Maximum 90 for a randomized controlled trial.

Where the score came from

Reporting0
Methodology39
Publication100
Statistical23
Study type (basis of the score)
Randomized Controlled Trial
Level 1b - Individual RCT
What’s the bottom line?

Scientists tested if taking creatine and caffeine together helps people lift more weights without changing their stress or sex hormones.

Where does this study sit?

Reviews of RCTs (Meta-analyses)

Max 100

Randomized Trials

Max 90

Reviews of Cohort Studies

Max 85

Cohort Studies

Max 72

Reviews of Case-Control Studies

Max 63

Case-Control Studies

Max 58

Cross-Sectional & Case Series

Max 50

Expert Opinion

Max 5
StrongerWeaker
Randomized Trials
Level 1b
39

39 / 100

Quality score

Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.

Cannot establish causation

Save studies & get personalized insights

Create a free account to save this study, track new evidence as it comes in, and get breakdowns of studies in the topics you care about.

Key takeaways

Summary

Based on the study abstract and findings.

  1. 1The increase in lifting volume is real but modest—likely helpful for athletes seeking small performance gains without hormonal side effects.
  2. 2People lifted more total weight when they took creatine and caffeine together than when they took nothing, but their hormone levels didn't change.

Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data

Publication

Journal

Sport Sciences for Health

Year

2026

Authors

Masoud Ramezanzadeh, H. Arazi, Payam Saidie

Fit Body Science verdict — we translate health studies into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.