What Is Creatine?
Creatine is a compound synthesised naturally in your body (primarily in the liver and kidneys) from the amino acids arginine, glycine, and methionine. It's stored primarily in skeletal muscle and the brain.
The role of creatine is to serve as a rapid energy buffer. In muscle, creatine combines with phosphate to form phosphocreatine (PCr), which rapidly regenerates ATP (the universal energy currency) during high-intensity activity.
The Phosphocreatine System: How It Works
Here's the mechanism:
- At rest: Creatine + phosphate → Phosphocreatine (stored in muscle)
- During intense effort (0-10 seconds): PCr + ADP → Creatine + ATP (resynthesises ATP rapidly)
- ATP is immediately available for muscle contraction
The phosphocreatine system is your fastest energy system. It's exhausted after about 10 seconds of maximal effort (a single set of heavy squats, a 100m sprint). Creatine supplementation increases muscle PCr stores by 15-30%, extending this high-intensity capacity.
This is why creatine is so effective: it directly increases the substrate availability for your fastest energy system.
The Evidence: 500+ Studies and Counting
Creatine is the most-studied supplement in sports nutrition. The International Society of Sports Nutrition (ISSN) position stand on creatine (Kreider et al. 2017) summarised evidence from 500+ trials:
Strength and power:
- Increases 1-rep max strength by 5-15% in resistance-trained populations
- Greater gains in untrained individuals (10-20%)
- Effect is consistent across ages (young to older adults)
Lean mass:
- Increases lean body mass by 1-2kg on average over 8-12 weeks
- This is genuine muscle gain, not just water retention (though some water retention occurs intramuscularly)
Cognitive function:
- Improves working memory and processing speed in sleep-deprived and fatigued states
- Evidence from Smith et al. (2020) shows creatine supports neuronal energy metabolism
- Benefits are more pronounced in vegetarians (who have lower baseline stores)
Anaerobic power:
- Increases repeated sprint performance (multiple sets of high-intensity effort)
- Benefits appear after 5-7 days of supplementation
Long-term efficacy:
- No evidence of tolerance or diminishing returns over months of use
- Benefits are sustained indefinitely with continued supplementation
This is not modest—a 5-15% strength gain is meaningful. In the context of a proper training programme, creatine is one of the few supplements with proven efficacy.
Mechanism: PCr Resynthesis
Why is creatine effective for strength?
During resistance training, your muscles are constantly depleting ATP and regenerating it via the phosphocreatine system. More creatine means:
- Faster ATP regeneration during sets
- Longer maintenance of high force production before fatigue sets in
- Ability to perform additional reps or sets at high intensity
- Greater mechanical tension over time (leading to hypertrophy)
This is mechanistic—increasing the substrate directly improves performance in the phosphocreatine-dependent energy system.
For sports with repeated high-intensity efforts (strength training, sprinting, rugby, football), creatine's benefit is clear. For pure aerobic endurance (marathon running), creatine provides minimal benefit.
Monohydrate vs Everything Else: No Clear Winner Alternative
Creatine monohydrate (creatine bonded to a water molecule) is the gold standard.
The supplement industry has created dozens of "improved" creatine forms:
- Creatine ethyl ester (CEE)
- Buffered creatine (Kre-Alkalyn)
- Liquid creatine
- Creatine hydrochloride (HCl)
Every single head-to-head comparison has found monohydrate to be equally or more effective than these alternatives. Some supposed advantages:
Buffered creatine claim: "Monohydrate is unstable; buffering prevents degradation." Reality: Monohydrate is stable at room temperature. In stomach acid, both forms convert to creatine anyway.
Creatine HCl claim: "HCl is more soluble; better absorption." Reality: Both absorb well. No consistent superiority in trials.
Liquid creatine claim: "Faster absorption." Reality: Creatine is absorbed at the intestine, not the stomach. Form doesn't matter.
The evidence is unambiguous: creatine monohydrate is as effective as any expensive alternative and significantly cheaper. Buy monohydrate.
Creapure Certification: What It Means
Creapure is a registered trademark for creatine monohydrate produced by AlzChem (a German chemical company) under strict manufacturing standards. Creapure certified creatine:
- Is pharmaceutical-grade (>99% pure)
- Is tested for impurities and heavy metals
- Has consistent crystal structure and particle size
- Meets GMP (good manufacturing practice) standards
Many quality supplements specify "Creapure certified" because it's a mark of reliability.
Is it necessary? No. Standard USP-verified creatine monohydrate is fine. But if two brands cost the same and one is Creapure certified, choose that.
The Kidney Myth: Thoroughly Debunked
The most persistent myth about creatine is that it damages kidneys.
The evidence:
- Decades of studies in healthy populations show no kidney damage markers (eGFR, serum creatinine, albumin:creatinine ratio)
- Kidney function is unchanged even in long-term use (5+ years)
- The International Society of Sports Nutrition concluded creatine is safe in healthy individuals
Why the myth? Creatine supplementation elevates serum creatinine (a kidney waste product). Doctors unfamiliar with creatine supplementation see elevated creatinine and assume kidney damage. In reality, elevated creatinine from creatine supplementation is not kidney damage—it's just higher creatinine from supplemental creatine. The real markers of kidney health (eGFR, albumin, electrolytes) are unaffected.
In people with existing kidney disease: Caution is warranted. If you have eGFR <60 or any kidney disease, consult your doctor before supplementing.
For healthy individuals, creatine is one of the safest supplements available. The adverse effect profile is genuinely minimal.
Creatine for Women: Under-Studied but Applicable
Most creatine research has been in men. However, the data available on women shows:
- Benefit is real: Women gain strength and lean mass from creatine, just like men
- Effect size is similar: 5-10% strength gains, 1-2kg lean mass gains
- Hormonal concerns are unfounded: Creatine does not elevate testosterone, DHT, or any androgenic hormones in women
- Safety is excellent: Same safety profile as in men
The barrier is simply that women weren't included in many historical studies. The mechanism (phosphocreatine availability) is universal.
For women: Supplementing creatine monohydrate offers the same benefits as for men. The dose, protocol, and safety profile are identical. This is not a male-only supplement.
Dosing: Loading vs Maintenance
Traditional protocol (faster saturation):
- Loading: 20g per day (5g, 4 times daily) for 5-7 days
- Maintenance: 3-5g per day indefinitely
Saturation: Muscle creatine stores become saturated (maximally elevated) after this loading period.
Alternative protocol (slower, easier):
- No loading: Start with 3-5g per day
- Duration: 4-6 weeks to reach saturation (slower than loading, but same final result)
- Maintenance: 3-5g per day indefinitely
Both work. Loading is faster (effects within 7 days) but requires larger acute doses. No-load is gradual but easier to sustain.
For strength training, 5g per day is the standard maintenance dose. Some research suggests individuals with larger muscle mass or higher body weight may benefit from slightly higher doses (5-7g), but 5g is optimal for most.
Timing: Does It Matter?
Timing with meals: Take creatine with a meal containing carbohydrates and protein. The insulin spike increases creatine transporter activity, improving muscle uptake. Taking creatine alone with water works, but with carbs is marginally better.
Pre-workout vs post-workout: Timing within the day is not critical. Creatine works via saturation of muscle stores, not acute dose. Daily consistency matters; timing within the day does not.
Hydration: Ensure adequate water intake (at least 2-3 litres daily). Creatine draws water into muscle cells; being dehydrated will reduce effectiveness and potentially increase muscle cramp risk.
Potential Side Effects and Mitigation
Water retention: Creatine draws water intracellularly (into muscle cells), not subcutaneously. You may gain 0.5-1kg of water weight in muscle, which is fine and partly reflects genuine muscle gain.
Muscle cramps: Some athletes report increased cramping on creatine. Mitigation: ensure adequate hydration and electrolyte intake (sodium, potassium, magnesium). This is usually solvable with hydration.
GI distress (from loading specifically): Taking 5g doses 4 times daily can cause bloating or loose stools. Mitigation: skip loading and use the slower protocol (3-5g daily from the start).
Increased body weight: You will gain 1-2kg initially (water + muscle). This is why creatine is not ideal for sports with weight classes—you'll move up a category.
For most people, these are minor or non-existent. Creatine monohydrate is exceptionally well-tolerated.
Long-Term Use and Safety
There is no evidence of harm from long-term creatine supplementation (5+ years) in healthy individuals. It's been used safely for 20+ years across millions of people.
Monitoring: If you have kidney disease, periodic kidney function tests (eGFR, creatinine, urinalysis) make sense. For healthy people, routine monitoring is unnecessary.
Stopping: Creatine is not habit-forming or dependency-creating. Stopping supplementation simply allows muscle creatine to deplete over 4-6 weeks. No withdrawal effects.
UK Brands Worth Considering
Bulk Creatine Monohydrate (Creapure):
- Pharmaceutical-grade, Creapure certified
- ~£0.02-0.03 per 5g serving if purchased in bulk
- Unflavoured powder, mixes in water or juice
- Best value for quality
MyProtein Creatine Monohydrate:
- Good purity, UK retailer
- ~£5-7 for enough to last 2-3 months
- Available flavoured or unflavoured
- Convenient
Optimum Nutrition Micronised Creatine:
- Micronised (finer particles) for easier mixing
- ~£10-12 for 60 servings
- Good quality, widely available
Reflex Nutrition Creatine Monohydrate (Creapure):
- UK-made, Creapure certified
- ~£12-15 for 200 capsules or powder
- Premium option
True Nutrition Creatine Monohydrate:
- US-made, high purity
- ~£8-10 via Amazon UK
- Good value
Where to prioritise: For pure cost-per-serving, Bulk Supplements wins. For convenience, capsules from MyProtein or Reflex work fine. Creapure certification is a nice-to-have but not essential.
Practical Supplementation Protocol
Week 1-7: Loading phase (optional, faster):
- 5g creatine monohydrate, 4 times daily (20g total), with meals containing carbs
- Or skip loading and go straight to maintenance (slower but easier)
Week 8+: Maintenance phase:
- 5g per day (typically post-workout with a meal)
- Continue indefinitely
- Take with water and ensure adequate hydration
Expected outcomes:
- Strength gains of 5-15% over 8-12 weeks
- Lean mass gains of 1-2kg
- Improved repeated sprint performance
- Possible modest cognitive benefits
Troubleshooting:
- If no strength improvement after 8 weeks: ensure consistent dosing, adequate hydration, and proper training stimulus
- If muscle cramps: increase hydration and electrolyte intake
- If GI distress: lower daily dose or split into multiple smaller doses
Where to Buy Creatine in the UK
- Bulk Supplements: https://www.bulk.com/uk/
- MyProtein: https://www.amazon.co.uk/s?k=myprotein+creatine+monohydrate&tag=maleoptimal-21
- Optimum Nutrition: Available via Amazon UK and major retailers
- Amazon UK: https://www.amazon.co.uk/s?k=creatine+monohydrate+powder&tag=maleoptimal-21
- Reflex Nutrition: https://www.amazon.co.uk/s?k=reflex+nutrition+creatine&tag=maleoptimal-21
- Holland & Barrett: https://www.hollandandbarrett.com/
Summary
Creatine monohydrate is the most evidence-supported, practical supplement for strength and power performance. 500+ studies show consistent benefits:
- 5-15% strength gains
- 1-2kg lean mass gains (over 8-12 weeks)
- Improved repeated sprint performance
- Cognitive benefits in fatigue/sleep deprivation
It's safe in healthy individuals. The kidney damage myth is thoroughly debunked. The effect is not supraphysiological—it's a legitimate performance tool with mechanistic basis.
For resistance training, particularly in the UK: 5g creatine monohydrate daily is sensible. It's cheap (Bulk Creapure ~£12 for several months), effective, and safe.
Expect 5-15% strength improvements over 8-12 weeks. This is real, measurable progress that compounds over years of training.
If you're serious about strength training, creatine is non-negotiable. It's one of the few supplements with genuine evidence backing it and a cost-to-benefit ratio that makes sense.