Creatine for cyclists: useful, or just extra weight?

Creatine has the reputation of a gym supplement — something for people who care about bench press, not about W/kg. That reputation is out of date, but the scepticism behind it is not entirely misplaced. Creatine does something real, and it is one of the few supplements with genuinely strong evidence behind it. The catch for cyclists is that it also makes you heavier.

So the honest question is not "does creatine work" — it does — but does what it does outweigh the extra kilo or so you carry up every climb? The answer depends almost entirely on what kind of riding you do.

What creatine actually does

Your muscles hold a small store of phosphocreatine, which exists to regenerate ATP — the molecule your muscle fibres actually spend — very quickly. It is the fuel system that covers the first few seconds of any maximal effort, before glycolysis and then aerobic metabolism take over. It is also the system that has to be rebuilt between efforts.

Supplementing creatine raises the amount of creatine stored in muscle by roughly 20% in people who are not already saturated. That larger store means slightly more work available at very high intensity, and — probably more usefully for a cyclist — faster restoration of that store between repeated efforts. Vegetarians and vegans typically start from lower stores and tend to respond more. Some people, perhaps one in five, barely respond at all.

Where the benefit is, by effort duration

This is the part most write-ups skip. Creatine's benefit is not general — it is concentrated at one end of the duration spectrum and disappears completely at the other.

The bars are a visual summary of the direction and consistency of the published evidence, not a measured percentage gain. Individual response varies a great deal.

The weight problem, with numbers

Creatine draws water into muscle cells. The typical result is around 1 to 2 kg of gain in the first week or two of a loading protocol — more with a fast load, less with a slow one. This is intracellular water, not bloating in any meaningful sense, and it is not fat. But gravity does not care where the mass is.

Half a minute is not nothing, but nor is it a catastrophe. The point is the trade: you are exchanging a small, permanent uphill tax for a benefit that only pays out in short, sharp efforts. If your season is hill climbs and long alpine sportives, that is a bad trade. If it is crits, cyclocross, track, or road racing that gets decided by attacks, it is a defensible one.

There is a useful nuance here. One well-controlled study of trained cyclists found that creatine did not improve overall 120 km time-trial performance — but power in the closing sprints, late in a long and depleting ride, was higher. That is a narrow benefit, and it is worth being honest that it is narrow.

Loading, or just taking it

The classic protocol comes from work in the 1990s that measured muscle creatine directly. Two routes reach the same saturation point:

A few practical points:

• Creatine monohydrate is the form to use. It is the one that has been studied to exhaustion, and it is the cheapest. The exotic variants sold at a premium have not shown themselves to be better.
• Timing barely matters. Saturation is about total daily intake over weeks, not about hitting a window. Take it whenever you will remember.
• It is not a taper supplement. If you are going to try it, do it in an off-season or base block — not in the fortnight before a goal event, when you do not want a novel gut experiment or a sudden 1.5 kg.
• Stopping is easy. Stores drift back to baseline over several weeks, and the water goes with them.

Is it safe?

Creatine monohydrate is among the most heavily studied supplements in existence, and the safety record in healthy adults is good — including in trials running for months to years. The persistent claim that it damages healthy kidneys is not supported by the evidence; the confusion largely comes from creatine raising blood creatinine, a marker used to estimate kidney function, without kidney function actually changing. That is worth mentioning to your doctor before a blood test, so nobody misreads the result.

The IOC's consensus statement on supplements lists creatine among the small handful with sufficient evidence to be considered for performance, alongside caffeine, nitrate, beta-alanine and bicarbonate. That is about as strong an endorsement as this category gets, and it still comes with the caveat about third-party testing.

The realistic downsides are mundane: gastrointestinal discomfort during a fast load, and the weight.

So: yes or no?

• Probably worth it if you race criteriums, cyclocross, track, or road events decided by repeated attacks — and if you also lift, which most riders should.
• Probably not worth it if you are a climber, a long-distance time triallist, or someone chasing a sportive up a mountain. You would be paying a W/kg tax for a benefit you rarely use.
• Irrelevant if your training, sleep or fuelling are not yet in order. Creatine is a rounding error next to those. The riders who gain most from a supplement are the ones who have already run out of bigger things to fix.

If you do want to see the trade-off in your own numbers rather than in an illustrative table, that is what a Moveee power profile is for: it estimates your FTP and your short-duration power from your actual rides, so a month on creatine shows up as a change in both absolute watts and W/kg, rather than as a feeling. If your five-second power rises and your 20-minute W/kg quietly falls, you have your answer.