Creatine for lifting and cardio: should you take it?

The practical, science-based guide (2024-2025 update).

If you train seriously (lifting, running, trail, triathlon, hyrox, concurrent training), you have heard of creatine. It is probably the most studied supplement in the world: more than 700 published studies, and a scientific consensus that has firmed up in recent years.

Yet the myths still circulate. "It damages your kidneys." "It makes your hair fall out." "It's only for bodybuilders." "It's useless for endurance."

This article sets the record straight. No bullshit, no marketing: just what the recent meta-analyses say, along with the official positions of the International Society of Sports Nutrition (ISSN), the world reference in sports nutrition.

What creatine is, in 30 seconds

Creatine is a molecule your body makes naturally (liver, kidneys, pancreas), about 1 gram per day. You also get it from food, mostly meat and fish.

Once in your body, 95% is stored in your muscles as phosphocreatine. Its job: regenerate your ATP, the immediate fuel for muscle contraction, during explosive efforts (0-10 seconds) and between sets.

The more phosphocreatine you have in reserve, the harder and longer you can push, and the faster you recover between intense efforts.

The catch? On a normal diet, your muscles run at 60-80% of their maximum storage capacity. Supplementing saturates those stores, and that is where the benefits come from.

To reach 5 g a day from food alone, you would have to eat about 1 kg of raw beef or 500 g of herring. You see the problem.

The benefits, study by study

In lifting: solid, measured and reproducible

This is where the evidence is overwhelming. A meta-analysis by Delpino et al. (2022) pooling 35 studies and nearly 1,200 subjects put a number on the gain: +1.1 kg of extra lean mass compared with a placebo, over programs lasting from a few weeks to a few months.

For context: 1.1 kg of extra muscle is what most people take 6 months to a year to build with serious training. Creatine does not replace the work, but it speeds up the result.

For strength, we are talking +5 to +15% on 1RM (the maximum weight you can lift once) depending on the exercise, with a larger effect on short movements (Lanhers et al., upper body and lower body).

And contrary to what was once thought, it also works for experienced lifters. The 2025 meta-analysis published in the JISSN on 61 trials shows a slightly larger gain in experienced lifters (+1.82 kg) than in beginners (+1.39 kg). The idea of a "ceiling" you would hit with experience is wrong.

In cardio and endurance: it's more nuanced

Here, honesty is required. The meta-analysis by Fernández-Landa et al. (2023, Sports Medicine) on 13 studies and 277 trained athletes concludes that there is no direct ergogenic effect on pure endurance performance. No magic on your marathon time.

But, and this matters, the same review states that sports with pace changes, surges and finishing sprints clearly benefit: cycling, cross-country skiing, mountain biking, triathlon, kayaking, rowing, trail running with explosive climbs.

In practice, the meta-analysis by Glaister & Rhodes (2022) on 14 studies confirms a significant improvement in mean power over repeated sprints (effect size δ = 0.61, a "moderate to large" effect in sports statistics: concrete and reproducible).

Concurrent training: where it is most versatile

If you combine strength and cardio in the same week, or even the same session, creatine becomes especially interesting.

The landmark study by De Salles Painelli et al. (2014) tested 32 trained men running 5 km followed by leg press and bench press. Result: creatine prevented the strength loss that the placebo group suffered after the cardio.

This is what reducing "interference" means: the well-known effect where your cardio drags down your strength performance on the same day. Creatine does not eliminate it entirely, but it significantly reduces it.

Bonus: it also speeds up glycogen resynthesis (the sugar stores in your muscles) by +82% when taken with carbohydrates (Roberts et al., 2016). That means recovering faster between two closely spaced sessions.

Recovery and inflammation: underrated

The study by Cooke et al. (2009) measured an 84% reduction in creatine kinase (a marker of muscle damage) 48-72 h after eccentric training. Translation: less soreness, faster recovery.

In triathletes who completed a half-Ironman, Bassit et al. (2010) showed that creatine significantly reduces inflammatory markers (TNF-α, IL-1β, etc.) after the race.

And, contrary to a persistent myth, Greenwood et al. (2003), following an NCAA season in the heat, observed fewer cramps, fewer heat injuries and fewer muscle strains in the supplemented players.

The brain too

This is one of the most active research areas right now. The meta-analysis by Prokopidis et al. (2023) confirms a positive effect on memory, especially in older adults and vegetarians.

But the study that made headlines is Gordji-Nejad et al. (2024) in Scientific Reports. They tested a single massive dose (0.35 g/kg, about 25 g for a 70 kg athlete) in subjects deprived of sleep for 21 hours. Result: better memory, processing speed and logical reasoning for 9 hours.

For an athlete who sleeps badly before a competition, who strings together a stage race, or who juggles work and training, that is far from trivial.

Vegetarian or vegan? You'll love this

Vegetarians and vegans have muscle creatine stores 10 to 20% lower than omnivores, because nearly all dietary creatine comes from meat and fish.

As a result, they are the best responders to supplementation. The study by Burke et al. (2003) measured +66% phosphocreatine and +2.4 kg of lean mass in supplemented vegetarians, vs +1.9 kg in supplemented omnivores.

Good news: all synthetic creatine monohydrates, Creapure® included, are vegan. They are produced chemically from sodium sarcosinate, with no animal raw material.

"Non-responders": 20 to 30% of people

It has to be said honestly: not everyone responds to creatine. Work by Syrotuik & Bell (2004) found that 20 to 30% of people have muscle stores that are already naturally saturated and get no extra benefit.

The typical non-responder profile: a low share of fast-twitch (type II) fibers, modest muscle mass, and already high baseline stores (often heavy red-meat eaters).

Which creatine to buy? The simple answer

Creatine monohydrate. Period.

You will see dozens of "innovative" forms on the shelves: HCl, Kre-Alkalyn (buffered), ethyl ester, creatine nitrate, citrate, malate, pyruvate... None has shown superiority over monohydrate in rigorous clinical trials. That is the official position of the ISSN (Kreider et al., 2017).

Worse, ethyl ester is actively discouraged: Spillane et al. (2009) showed that it quickly breaks down into inactive creatinine in the stomach. You pay more for a less effective product.

Kre-Alkalyn? Jagim et al. (2012) compared it head to head with monohydrate using muscle biopsies: strictly equivalent. The marketing around "gastric resistance" has no physiological basis.

Is the Creapure® label worth the extra cost?

If you can afford it, yes.

Creapure® (made by AlzChem in Germany) guarantees purity ≥ 99.9%, very low levels of contaminants such as dicyandiamide and dihydrotriazine, and anti-doping certifications (Cologne List®).

If you cannot get Creapure®, at least look for the Informed Sport or NSF Certified for Sport labels. They guarantee the absence of contaminants and doping substances.

How to dose: the simple version

3 to 5 grams a day, every day, for life. That's it.

No need to cycle (take breaks). No need for a loading phase (unless you want fast effects). No need for complex timing.

The two possible protocols

In the end, both give exactly the same result (Hultman et al., 1996). The total cumulative dose is what counts, not the pace.

My advice: unless you have a competition in 2 weeks, go with the easy protocol. Simpler, better tolerated.

Timing: less important than consistency

The "Creatine O'Clock" review by Candow et al. (2022) is clear: the advantage of post-workout timing is marginal and not robust.

The practical rule: take your dose at a regular, easy-to-remember time, ideally with a meal. With carbohydrates + protein, you slightly improve initial retention (insulin helps carry creatine into the muscle, as shown by Green et al., 1996).

In practice? Mix it into your post-workout shaker, or have it with breakfast. Both work. On rest days, any time.

Side effects: what's true, what's false

Myths that collapse under scientific scrutiny

"It damages your kidneys." No. The review by Kreider et al. (2021), the most comprehensive on the subject, confirms no kidney impairment in healthy subjects, including at 30 g/day for 5 years. Blood creatinine rises slightly, but that is a normal metabolic artifact (creatinine is the breakdown product of creatine), not a sign of kidney failure. The myth comes from a single 1998 clinical case in a patient with pre-existing kidney disease who was on an immunosuppressant.

"It makes your hair fall out." The myth rests on a single 2009 study in 20 South African rugby players, which showed a transient rise in DHT (the hormone associated with androgenetic baldness). No hair assessment was done. The 2025 randomized controlled trial, the first to directly measure hair density and thickness over 12 weeks, found no significant difference between creatine and placebo.

"It dehydrates you and gives you cramps." It is exactly the opposite. Creatine increases intracellular water (inside the muscle, where it is useful), and the meta-analysis by Lopez et al. (2009) confirms it does not interfere with thermoregulation.

The real side effects (but manageable)

Water weight gain: 0.5 to 1.5 kg over the first weeks, in the muscles. It is a desired effect, not a problem. For weight-class sports, stopping 4-6 weeks before the weigh-in allows a complete washout. For long-distance runners, the impact on running economy is negligible (Beis et al., 2011).

Digestive issues: they are dose-dependent. Ostojic & Ahmetovic (2008) measured 55.6% diarrhea with a single 10 g dose, versus only 28.6% when split into 2×5 g. Solutions: split the dose, take it with a meal, choose micronized creatine.

How long before you see the effects?

• With a loading phase (20 g/day): measurable ergogenic effects from 1 to 2 weeks.
• With the direct approach (3-5 g/day): visible effects between the 2nd and 4th week.
• Strength and power gains: 2 to 4 weeks for the first ones, maximal effect between 4 and 12 weeks.
• Hypertrophy (muscle gain): visible over 4 to 8 weeks with structured training.
• Cognitive effects under sleep deprivation: from 3 hours with a single high dose.

After stopping completely, muscle washout takes 4 to 6 weeks. And good news: supplementation does not durably suppress endogenous production. You can stop and restart without a problem.

Final recommendations by profile

If you mostly lift: 3-5 g/day of Creapure® monohydrate post-workout. A clear benefit on lean mass and strength.

If you mostly do long cardio (marathon, ultra-trail): the decision is more balanced. Direct benefit on pure endurance performance: small. Benefit on recovery between sessions, injury prevention and cognition: real. Dose: 3 g/day, or targeted at intense training phases.

If you do triathlon, hyrox, technical trail with surges, or concurrent training: strong recommendation. This is the ideal profile for creatine. 3-5 g/day continuously, no cycling.

If you are vegetarian or vegan: best responder, maximum expected benefit. Standard dose, and it also improves your cognitive performance.

In one sentence

For 95% of athletes combining lifting and cardio, the question is no longer "should I take creatine?" but "why wouldn't I?". It is safe, it is effective, it is cheap (15-30 € for 3 months of Creapure®), and it is one of the very few supplements whose benefits are this well documented.

This article presents the current scientific data. For a personalized program, consult a healthcare professional.