🛒 Recommended Supplements
Why Kidney Health Is Relevant to Athletes?
The kidneys filter ~180 liters of blood per day, remove waste products (creatinine, urea), regulate electrolyte and fluid balance, blood pressure, activate vitamin D and produce erythropoietin (EPO). In athletes, the kidneys experience an additional load due to: high protein intake (nitrogen waste), muscle breakdown products after training, creatine (creatinine), risk of dehydration, supplement metabolites.
It is important to distinguish: a physiological increase in creatinine (normal for athletes!) from a true deterioration in kidney function.
📊 Kidney Function Markers
| Metric | Requirement | What It Means for Athletes | Notes |
|---|---|---|---|
| Blood Creatinine | 0.7–1.3 mg/dL (for men) | Athletes OFTEN have higher levels due to greater muscle mass and creatine use | Does not necessarily indicate a kidney problem! |
| eGFR (calculated GFR) | >90 mL/min/1.73m² | May be falsely reduced due to high creatinine (formula limitation) | Request a cystatin C test for more accurate GFR |
| Urea (BUN) | 7–20 mg/dL | May be higher due to high protein intake | Together with creatinine, assesses kidney function |
| Cystatin C | 0.5–1.0 mg/L | A more accurate GFR marker for athletes — independent of muscle mass! | Recommended for athletes instead of creatinine |
| Microalbuminuria | <30 mg/g kreatinino | An early marker of kidney damage. Protein in urine | Test if risk factors are present |
🔬 Does High Protein Intake Harm the Kidneys?
Scientific consensus 2024–2026: For HEALTHY people, high protein intake (up to 2.5–3.0 g/kg) does NOT harm the kidneys. Studies in athletes consuming 2.5–3.5 g/kg of protein per day for years show no deterioration in kidney function.
However:
- In the presence of kidney disease: Any increase in protein intake may worsen the condition. If you have kidney problems (eGFR <60, proteinuria) — protein is strictly controlled (0.6–0.8 g/kg).
- Dehydration + protein: High protein intake + insufficient water intake = greater kidney load. Always drink enough water!
- Creatine and the kidneys: Creatine INCREASES blood creatinine levels but does NOT damage the kidneys. It is important to know this before a blood test — inform your doctor that you use creatine!
📋 Kidney Protection Protocol
Hydration — Most Important!
35–40 ml/kg of water per day. When exercising — an additional 500–1000 ml per hour. Monitor urine color — it should be light yellow, not dark.
Do Not Exceed 3.0 g/kg Protein
There is no evidence that >3.0 g/kg provides additional benefit for muscle growth, but kidney load increases. Stick to 1.6–2.5 g/kg.
Avoid NSAIDs (Ibuprofen) Before and After Training
NSAIDs reduce renal blood flow, especially during dehydration. After a hard workout + NSAIDs = risk of acute kidney injury!
Drink Electrolytes, Not Just Water
When sweating intensely, you lose not only water but also sodium, potassium, and magnesium. Electrolyte drinks or salt supplementation help the kidneys maintain balance.
Monitor Blood Pressure
High blood pressure is the #1 cause of chronic kidney disease. Measure it regularly, especially if you use stimulants (caffeine, pre-workout).
Limit Excess Oxalates (Kidney Stone Prevention)
Spinach, nuts, beets, tea — are high in oxalates. If you are prone to kidney stones, limit them and drink plenty of water with lemon (citrates reduce the risk of stones).
💡 Health Maintenance Strategies
🩺 Regular Tests
Preventive blood tests at least once a year. For athletes, more frequent testing is recommended — every 6 months to monitor liver, kidney, and lipid markers.
💧 Hydration — Always
Sufficient water intake is the cheapest and most effective means of protecting organs. 35–40 ml/kg daily, more when exercising.
🥗 Balanced Nutrition
Not just supplements — whole foods are the foundation of your organ protection. Vegetables, fruits, healthy fats, lean proteins.
🏋️ Smart Training Load
Periodize your training. Excessive chronic load harms all organs. Recovery is part of training!
❓ Frequently Asked Questions
Q: Can exercise harm organs?
A: Properly dosed exercise is only beneficial. The problem arises only with extreme loads (ultramarathons, overtraining) and the use of prohibited substances.
Q: How often should organ function be checked?
A: For athletes taking many supplements — a full biochemical test at least once a year. If there are risk factors — every 6 months.
Q: Can supplements replace a healthy lifestyle?
A: No! Supplements are an auxiliary aid. No liver detox supplement will replace healthy nutrition and avoiding alcohol.
🧠 Myths and Truth
❌ Myth: It works the same for everyone
✅ Truth: Everyone's body is unique. Genetics, hormone levels, training experience, and dietary habits determine the individual response. What works for one person will not necessarily work for another.
❌ Myth: The more, the better
✅ Truth: More is not always better. Too high doses, too frequent training, or too long a protocol can have the opposite effect. The sweet spot is the key to success.
❌ Myth: Results are visible immediately
✅ Truth: The body needs time to adapt. The first changes — within 2–4 weeks. Significant results — within 8–12 weeks of consistent work. Patience is essential!
❌ Myth: Supplements will solve all problems
✅ Truth: Supplements are only an auxiliary aid. Without proper nutrition, sleep, and training — no supplement will work. First, get the basics in order!
⚠️ Don't Forget
Important!
This information is for educational purposes. Before changing your nutrition, starting supplements, or changing your training regimen, consult a sports medicine physician or a certified nutrition specialist.
Individual recommendations are always more precise than general guidelines. Listen to your body!
📚 Additional Resources
Want to learn more? Here are several reliable sources of information:
- PubMed / Google Scholar — the latest scientific research on this topic. Look for meta-analyses and systematic reviews.
- ISSN (International Society of Sports Nutrition) — recommendations from sports nutrition specialists, based on science.
- Blood tests — the most objective way to assess your condition. Consult a doctor about targeted tests.
- Certified Sports Nutrition Specialist — an individual consultation will help tailor the recommendations specifically to you.