Purist or pill popper: Who's in the right when it comes to sports supplements?

A recent CW survey revealed a stark divide in opinion on sports supplements. But who wins this debate, asks Chris Marshall-Bell, the purists or the pill-poppers?

(Background Image: Getty)
(Image credit: AFP via Getty Images)

How long would it take you to eat half a cow? No, we don’t know either. But if you wanted to get a 20g dose of creatine from a natural food source, that’s what you would need to do. 

“We ordinarily get 2g of creatine a day,”  explains Luc van Loon, a professor of physiology and nutrition at Maastricht University in the Netherlands, “a gram through a normal diet and a gram that we produce naturally. But with creatine supplements, you’re loading 20g a day. To get that in a normal diet, you’d have to eat half a cow. We can’t sustain that in a normal, nutritious diet.”

Creatine is one of the most popular sports supplements worldwide – a market worth more than £40bn and which continues to grow. Supplements crop up all the time when chatting to cyclists. It’s quite hard to define exactly what a sports supplement is, but the vast majority of them – whether in bar, drink, tablet or powder form – claim to benefit an athlete’s performance in a ‘natural’, legal manner. 

But eating half a cow’s worth of creatine in a single dose – for example – doesn’t strike me as very natural. Are supplements really in keeping with the spirit of the World Anti-Doping Code or the unwritten sporting code between competitors? Besides, do supplements really make a difference anyway? 

>>> Subscriptions deals for Cycling Weekly magazine

We decided to investigate further by conducting an online poll of Cycling Weekly readers, asking about their use of supplements. The results revealed a split, broadly speaking, between two contrasting camps – those who take lots of supplements and those take none at all. It appears to be something of a ‘Marmite’ debate. 

Eighty-two per cent of the 220 people surveyed take at least one supplement each week – predominantly protein or energy products and vitamins. Of those who took none, most believed that supplements didn’t work or that a normal diet was sufficient and covered all their nutritional needs. 

This got us wondering: is it better to pursue a bread-and-water, purist approach to cycling nutrition, or a full marginal gains strategy? No supplements at all, or the full complement? 

The purist’s view

From our survey data, we have sketched two rider archetypes at either end of the spectrum – both are realistic depictions without being based on any single real person. First up, meet Mr Purist, our fictional bread-and-water cyclist – a phrase made famous by Bradley Wiggins during the lead-up to his 2012 Tour de France triumph, when he rejected accusations of doping by stating many times, “I want to prove I’m doing this off bread and water and hard work.”

Mr Purist is a club rider who has raced a few crits in the past and typically rides several sportives each year, occasionally going to Majorca for a spring training camp. He fuels his cycling solely with grocery purchases, filling up on home-cooked pasta before a big ride. During the ride, he munches away on homemade flapjacks and bananas, and afterwards has a good wholesome meal – he’s a meat-and-two-veg kind of guy.

Mr Purist wouldn’t be seen dead taking a supplement or eating a pre-packaged sports nutrition product. Like 60 per cent of those who don’t take supplements, he avoids them partly because he doubts the claimed benefits. He also thinks a good diet is sufficient, sharing the view of 72 per cent of non-supplement-taking respondents. Mr Purist regards these products as a waste of money, since he prides himself on his rational scepticism and frugality.

Hampshire-based rider Iain McCauley fits this description perfectly. A nurse, trained personal trainer and former army officer, McCauley has two bikes, heads out into his local lanes and hills every weekend and uses his bike as his principal form of transport. “I am cynical, but not dismissive of supplements for a variety of reasons,” says the 56-year-old. “I think the science is open to fairly considerable criticism and the results are very subjective. Beyond international athletes, it is really difficult to demonstrate any significant benefits from any of these products, including energy drinks and caffeine shots.”

McCauley has clearly done his research on supplements; he isn’t acting only on gut instinct.

“I am cynical about the marketing and skewed interpretation of the science, often pushed by people who are not the best equipped to advise. From what I’ve read, the gains are minimal when compared to a normal diet.”

Brent Ruby, professor of sports physiology at the University of Montana, USA, largely supports McCauley’s view: “I am very much of the opinion that supplements are not worth it. Certainly, 99.9 per cent of those who consume them have no reason to take them.”

In our survey, 42 per cent of those surveyed said they believed supplements can fill gaps and omissions in a cyclist’s diet. Ruby disagrees: “The liver and muscles couldn’t care less if the source is potatoes, corn, beet or something else. They only care that the total intake of carbs, protein and other nutrients satisfy the bottom line. You can easily get adequate amounts even from a mediocre diet – there is an enormous amount of flexibility and wiggle room.”

Mr Purist has ethical concerns about what exactly supplements contain. Only 42 per cent of supplement users surveyed checked that the products they bought had been batch-tested for contaminants (as signified by the Informed-Sport logo). They might want to think again after hearing from van Loon: “Several studies have asked athletes to bring in their supplements to have them anonymously checked...the results show that around 25 per cent of products contain stuff on the doping list.”

This does not mean that a quarter of all supplements are contaminated, since the athletes in the aforementioned studies tend to submit the products about which they have doubts. Nonetheless, it’s a worrying figure – though it does not surprise McCauley. “Who controls what goes into these things?” he asks rhetorically. “It’s completely uncontrolled. In the last 10 years, the number of soldiers failing drug tests because of stuff they consumed in dietary and sports supplements has increased dramatically.”

Removing the shield

While common nutritional products such as beta-alanine, amino acids, vitamins and protein bars are highly unlikely to spiral into the use of banned drugs, there is evidence that supplements can be a ‘gateway’ into doping – one in four in our survey believed this was a risk, while 18 per cent said they had or would consider obtaining a prescription drug so as to gain a performance advantage. 

Van Loon is concerned that some athletes gradually become more indiscriminate and blasé around legality. He says: “If you tell a younger athlete to take something without informing them what it contains and they don’t question it, it makes them less inquisitive – removing a key shield against doping.”

Most nutritional supplements are perfectly safe, of course, and do not present a hazard. However, there is an expanding category of what van Loon refers to as ‘nutriceuticals’. These are products “in the grey area between pharmaceutical and food”. He homes in on high-dose creatine.

“Nutriceuticals contain stuff that we can’t get in a normal diet. Morally and ethically, should you be using them? If your life depends on the performance, then most people will. But I don’t see the point in amateurs taking nutriceuticals. Most of the stuff doesn’t work, and when it does, it only works on one very specific area.”

Ruby airs similar worries: “I am adamantly opposed to younger athletes taking supplements by default. The problem is, if they get a taste for them and it makes them feel different, they will reach for the next one. It’s a slippery slope.”

His point is that this level of supplement intake is not subtly augmenting a normal diet, it’s pushing nutrition into highly unnatural ranges. He urges athletes to instead go back to basics: “If they want to improve their performance, they should do more consistent training and, if necessary, lose weight.” 

In his book The Line: Where Medicine and Sport Collide, Dr Richard Freeman wrote: “The problem is that we’ve been fooled into thinking that taking supplements is intrinsically sporty. It’s part of what I like to think of as the ‘medicalisation’ of sport, and while it makes money for the supplement company, it is not key to athlete welfare.”

Given that the former Team Sky and British Cycling doctor is currently embroiled in a medical tribunal, you have to wonder whether he should have followed his own advice more stringently – and whether we should, too.

Supplement taker’s side

(Photo Illustration by Frank Bienewald/LightRocket via Getty Images)
(Image credit: LightRocket via Getty Images)

Mrs Marginal – Marg to her friends – is our fictional ‘full marginal gains’ athlete. She races at local level and, under normal circumstances, goes abroad each year on a training camp. Marg spends around £20 a month on supplements, taking between two and three a day, including vitamins, caffeine shots, amino acids, iron, creatine, nitrate and protein products. 

Italian amateur rider Luca di Pierro, 34, is our real-life equivalent. “I spend between €500 to €600 a year on supplements and to be followed by a sports doctor and nutritionist,” he says. Private medical support aside, di Pierro’s views are representative of riders who value supplements. He takes vitamins, protein, BCAAs, glutamine and occasionally iron products. “I do so because it makes me less likely to go into over-training, and it speeds up recovery.” 

A massive 80 per cent of those who took part in CW’s survey said they take supplements for improved recovery, with enhanced power, strength and general health also commonly cited. Florence-based di Pierro adds: “Since being followed by a doctor, I’ve not had over-training issues, and I think that if I stopped taking the supplements, I would have trouble with recovery.” 

It’s a view shared by Robin Strong, another rider who embodies a ‘marginal gains’ approach. The London-based Scotsman, who has just turned 50, is a third-cat racer in the Surrey League and each year undertakes a big bike-packing challenge. Soon after beginning cycling a decade ago, he began adding protein powder to his diet, before supplementing it with vitamins, creatine, beta-alanine and amino acids. To combat knee problems, he then added collagen, glucosamine and chondroitin. 

“I noticed the difference immediately,” he reports. “I can’t prove if it’s one product or all three, but I feel like they have helped.” Would his knee worsen if he stopped taking them? “I can’t give a concrete answer, but I think I’d have knee joint issues again. I don’t want to take the risk and upset the apple cart now.”

Sceptics contend that it is only the placebo effect from supplements that increases performance. However, from our survey, a huge 71 per cent of supplement users said that the products had increased their performance at least a little, with 23 per cent reporting a significant increase.

It’s important to reiterate that supplements are legal products – with significant backing from many experts. Laura Martinelli, nutritionist for WorldTour team Bahrain Victorious, says: “Personally, I don’t agree with those who have ethical concerns. Supplements are a little ‘plus’ that can help people to recover better, sleep better, acclimatise better... I have absolutely no concerns.” 

Martinelli discloses that pro riders typically take between three and four supplements a day, which she regards as most beneficial during periods of high intensity when riders “are forcing their bodies to do something that is against nature, against physiology”. She adds: “Supplementation is a key aspect in trying to sustain extreme training loads. Riders need a daily supplementation schedule even if they eat healthily, because the body can’t afford to do it alone.”

Mrs Marginal isn’t a pro rider and rarely endures very high training loads, except perhaps once or twice a year.

Does Martinelli think our amateur rider is justified in taking supplements? “There are periods of the year when the amateur rider is much more prone to be stressed than a professional – they have work stresses and can only train around work hours. They might require some supplementation for helping them to recover from training and also as prevention of upper tract respiratory issues.” 

What about the issue of fairness? Is it morally right for Mrs Marginal to appear at a midweek club ‘25’ potentially optimised by her £22-per-month’s supply of supplements, competing against riders who can’t afford that outlay? The argument holds no water with van Loon. “If we go cycling and your bike is 10 times the price of mine, are you dishonest? I work so much that I have less time to train than you – so nothing is fair... Why are my genetics rubbish? Is that fair?” 

Our supplemented amateur di Pierro believes he has every right to pursue a marginal gains approach just like the pros. Like many committed amateurs, he aims to mimic the habits of pro riders as closely as possible.

“When cycling starts to get serious, riding at least four days a week, you should speak to someone who can help your nutrition,” adds di Pierro. “We might spend €10,000 on a bike, so what is €100 on professional consultation towards your health? It’s a much better return to spend €600 on nutrition, rather than on the latest [weight-saving] component.”

>>> Cycling Weekly is available on your Smart phone, tablet and desktop

Fellow amateur Strong agrees. “If you don’t keep your chain clean, the added friction knocks a few per cent off the drivechain efficiency and hurts performance,” he says. “For most people, it doesn’t matter, but to me it does matter. So I keep fit, keep my bike engine in good shape and my diet in shape.”


So who should you aim to imitate, Mr Purist or Mrs Marginal? If we were to take all the evidence-backed supplements for a year, would we end up as a fitter and faster cyclist than he or she who took none at all over the same period of time? The fact that it is impossible to answer that question with any confidence tells its own story.

The only sensible answer is that supplement use largely depends on your goals. If your cycling performance is paramount and you can afford supplements, as well as having the time to select and use them correctly, as a backup supporting a healthy diet, then go right ahead – just don’t expect miraculous results. 

On the other hand, given that our wages as amateurs are not dependent on our results, are supplements worth it? In purely monetary terms, probably not. Unless you have a specific deficiency, the benefits will be subtle, if not negligible.

And the money you save could be spent on better-quality food or put towards coaching support. Most of us have room for improvement in our training regimes and diet – and most of these improvements are free of charge, as well as being highly effective. 

There is a place for supplements, but they should be considered the finishing touch, explored with caution, not the go-to for improving performance.

Scientist’s view: Why do pros take supplements

We contacted a number of current and retired WorldTour and domestic pros to ask why so many of them take supplements, but none of them responded. So we instead asked Asker Jeukendrup, a renowned sports nutrition scientist who has worked with WorldTour cyclists. 

“The biggest reason elite athletes take supplements is that they don’t want to miss out on anything,” said Jeukendrup. “When a new supplement comes onto the market and an athlete using it performs well, other athletes think ‘maybe I should also take it?’ They begin to doubt themselves and take it just in case.

“Another reason is that elite athletes have a strong belief that they need more [nutrients]. Very often it’s not true, but they take supplements as an insurance policy. Perhaps their diet isn’t perfect, or when they travel it won’t be, so they use supplements... really believing that it will give them the edge, and help performance and recovery.”

Jeukendrup emphasised that sports drinks, gels and bars, i.e. supplementary carbs, protein and caffeine, definitely do work. Supplements not geared towards fuelling are more contentious – but a shortage of evidence doesn’t seem to harm their popularity in elite sport. 

“Their usage isn’t based on evidence, but more marketing claims,” Jeukendrup added. “Pros believe the hype because they don’t want to miss out. Most know that the evidence either isn’t very strong or doesn’t exist at all. But there are so few studies that if they wait for 20 positive studies, they might miss out on benefits their rivals didn’t miss. Athletes want to be innovating, doing something different and working with the latest products all of the time.”

Ketones controversy: The mysterious fasting chemical

(Photo by Michael Steele/Getty Images)
(Image credit: Getty Images)

When it comes to the moral debate over supplements, the supplement it’s impossible to ignore is ketones. In natural form, ketones are made by the liver when the body is running low on carbohydrate; they’re an alternative source of energy. High levels of ketones, however, are associated with serious health problems. 

In recent years, the popularity of ketone products has exploded, with some brands claiming that they increase physical endurance by 15 per cent, while also increasing fat-burning, weight loss and improving sleep. 

WorldTour team nutritionist Laura Martinelli says: “Ketones are very fascinating, and we are going to see something really interesting in the future linking ketones and performances and training. They can have all kinds of performance and recovery benefits.”

It is reported that several WorldTour teams use ketones, but few have publicly admitted to it, shrouding the supplement in suspicion. Team DSM, formerly Sunweb, reportedly punish riders who take ketone products. Jumbo-Visma, however, are open about their usage, but the Dutch anti-doping authority said that it “finds it uncomfortable” and that it “advises [athletes] not to use ketones… [because] too little is known about the possible health consequences”.

This feature originally appeared in the print edition of Cycling Weekly, on sale in newsagents and supermarkets, priced £3.25.

You can subscribe through this link here.

That way you’ll never miss an issue.

Thank you for reading 20 articles this month* Join now for unlimited access

Enjoy your first month for just £1 / $1 / €1

*Read 5 free articles per month without a subscription

Join now for unlimited access

Try first month for just £1 / $1 / €1

Chris Marshall-Bell

Chris first started writing for Cycling Weekly in 2013 on work experience and has since become a regular name in the magazine and on the website. Reporting from races, long interviews with riders from the peloton and riding features drive his love of writing about all things two wheels.

Probably a bit too obsessed with mountains, he was previously found playing and guiding in the Canadian Rockies, and now mostly lives in the Val d’Aran in the Spanish Pyrenees where he’s a ski instructor in the winter and cycling guide in the summer. He almost certainly holds the record for the most number of interviews conducted from snowy mountains.