Volek et al. 1999: Creatine and Testosterone Response — Study Summary

Study Overview

Volek et al. (1999) investigated the hormonal responses to creatine supplementation combined with resistance training. This study was among the early research addressing the common question of whether creatine’s performance benefits were mediated through testosterone or other anabolic hormones (JS et al., 1999) .

Key Findings

• Resting testosterone unchanged: Creatine supplementation did not significantly alter resting total or free testosterone levels compared to placebo
• Performance improved independently: Despite no hormonal changes, the creatine group showed significant improvements in strength and power output during resistance exercise
• Acute hormonal response preserved: The normal acute hormonal response to resistance exercise (transient testosterone elevation) was maintained in both creatine and placebo groups
• Muscle growth via non-hormonal mechanisms: The study supported the conclusion that creatine’s anabolic effects occur through enhanced energy availability, cell volumization, and increased training capacity rather than hormonal modulation

Practical Implications

This study is important for correcting the misconception that creatine is a hormonal supplement or steroid-like compound. Creatine’s benefits come from bioenergetic mechanisms — specifically, increasing the phosphocreatine pool available for rapid ATP regeneration during high-intensity exercise. This distinction matters for athletes subject to anti-doping regulations, as creatine is not a banned substance precisely because it is not hormonally active. For Malaysian athletes concerned about whether creatine affects hormones or is a steroid, this research provides clear reassurance that creatine works through entirely different pathways than anabolic steroids.

Study Limitations

• Sample size was relatively small, typical of exercise science studies from this era
• Only male participants were included, so results cannot be directly extrapolated to women
• Hormonal measurements were taken at rest, and more subtle exercise-induced hormonal shifts may have been missed
• The study duration was relatively short, and chronic hormonal adaptations over many months were not assessed

Mechanism of Action

Understanding the biochemistry behind creatine’s effects provides context for the practical recommendations in this guide. Creatine functions primarily through the ATP-phosphocreatine (ATP-PCr) system:

1. Storage: Approximately 95% of the body’s creatine is stored in skeletal muscle, with the remaining 5% in the brain, kidneys, and liver
2. Conversion: The enzyme creatine kinase attaches a high-energy phosphate group to free creatine, creating phosphocreatine (PCr)
3. Energy release: During high-intensity activity, PCr rapidly donates its phosphate group to ADP, regenerating ATP within milliseconds
4. Resynthesis: During rest periods, the process reverses — ATP donates a phosphate back to creatine, replenishing PCr stores

This cycle operates continuously in all metabolically active tissues. Supplementation increases the total creatine pool by 20-40%, expanding the energy buffer available for intense physical and cognitive work.

Practical Application

Translating the science into actionable steps:

Dosing Protocol

• Standard maintenance: 3-5g creatine monohydrate daily, taken with any meal
• Optional loading phase: 20g/day split into 4 x 5g doses for 5-7 days (faster saturation but not required)
• Body-weight adjustment: Individuals over 80kg may benefit from the upper range (5g); those under 60kg can use the lower range (3g)

What to Expect

Combining with Other Strategies

Creatine works best as part of an integrated approach:

• Progressive resistance training — creatine amplifies the results of structured training programmes
• Adequate protein intake — 1.6-2.2g/kg/day supports the muscle-building effects of creatine
• Sufficient sleep — 7-9 hours per night for optimal recovery and muscle protein synthesis
• Consistent nutrition — creatine is not a substitute for a well-balanced diet

Evidence Quality Assessment

When evaluating claims about creatine, consider the hierarchy of evidence:

1. Systematic reviews and meta-analyses — the strongest evidence, pooling data from multiple studies. Creatine has numerous favourable meta-analyses
2. Randomised controlled trials (RCTs) — well-designed experiments with control groups. Creatine has 500+ published RCTs
3. Observational studies — useful for identifying associations but cannot prove causation
4. Case reports and anecdotes — the weakest evidence, useful for generating hypotheses but not for making recommendations

The recommendations in this article are based on level 1-2 evidence wherever possible.

Malaysian Context

For readers in Malaysia, several local factors are worth considering:

• Climate: Malaysia’s tropical heat (27-33 degrees Celsius average) and high humidity increase fluid requirements. Supplement creatine with 2.5-3.5 litres of daily water intake, more during intense outdoor activity
• Halal considerations: Unflavoured creatine monohydrate powder is synthetically produced and generally considered permissible. See our halal creatine guide for brand-specific verification
• Affordability: Creatine is one of the most cost-effective supplements available in Malaysia, starting from RM0.50 per serving. See our price comparison guide for current pricing
• Availability: Widely available through Shopee, Lazada, and specialty supplement shops across Peninsular Malaysia, Sabah, and Sarawak

For personalised dosage recommendations, try our creatine dosage calculator.

Sources & References

This page summarizes Volek et al. (1999). Full citation: Volek JS, Duncan ND, Mazzetti SA, Staron RS, Putukian M, Gomez AL, Pearson DR, Fink WJ, Kraemer WJ. Performance and muscle fiber adaptations to creatine supplementation and heavy resistance training. Medicine and Science in Sports and Exercise. 1999;31(8):1147-1156.

What This Means for You

For the average creatine user, this research supports the following practical recommendations:

1. Choose creatine monohydrate — it remains the most studied and effective form
2. Take 3-5g daily — consistent daily dosing is more important than timing
3. Take it with food — insulin response from meals enhances muscle uptake
4. Be patient — full saturation takes 3-4 weeks without loading
5. Combine with exercise — creatine works best when paired with resistance or high-intensity training

For more on practical dosing strategies, see our creatine dosage guide.

Further Reading

• creatine for muscle building
• how creatine works
• buying creatine in Malaysia
• creatine for women
• creatine stacking guide
• creatine and protein