Sign up for our newsletter

We tried legal doping, and this is what happened

11 Mar 2020

Ketones, that’s the thing. Perhaps a ketogenic diet. They’re all on salbutamol, fluticasone, codeine, caffeine. People say they use beetroot juice, nitrates in the water bottle, bicarbonate of soda before the race and there’s this protein gene – it costs £100 a shot and apparently it gives you a 10% boost. Everyone’s on it...

Words Peter Stuart

When it comes to discussions about what the pros use to enhance performance without risking a doping ban, there is a lot of speculation but very little fact.

The list of foods, supplements and chemicals that potentially offer a speed boost is huge, and the benefits uncertain, so Cyclist decided to get the truth from the experts and to test claims for ourselves.

That’s how I come to find myself surrounded by a small mountain of elixirs, pill packets and tubs of powder, with six weeks of testing ahead of me to see if any of these – entirely legal – products can turn me into a faster, stronger rider.

Jump to:

The grey area: How the line between legal and illegal substances can be blurred  
Pills and powders: What legal substances can you take to improve performance?  
A hasty high: Choosing supplements for our own journey  
The programme: How much we took, how we tested the results  
The data drop: What differences legal doping made  
Into the detail: the full test results  


The grey area: How the line between legal and illegal substances can be blurred

My first task is to ensure that anything I take is safe and in no way considered dodgy by the doping authorities. It’s not always clear-cut.

Froome's Salbutamol case

Most keen cycling fans will remember the controversy that surrounded Chris Froome in 2018. A test suggested that he had exceeded the maximum permitted dosage for asthma medication salbutamol (which we'll return to in more detail later).

Froome was cleared of wrongdoing as he and Team Sky were able to prove that the levels of salbutamol in his urine were within an expected range of variation based on a permitted amount. At the time, studies flew back and forth arguing whether salbutamol offered any likely performance benefits, and whether it was being abused by some cyclists.

Sharapova's Meldonium case

Another pertinent example of the grey area involved tennis star Maria Sharapova. She was sanctioned for the use of meldonium, a drug that had been legal to use in competition until it was banned at the beginning of 2016.

She continued to take it after the ban, unaware that meldonium was a synonym for mildronate, a medication she was understood to be permitted under WADA rules. The medicine was usually used to treat ischaemia, a lack of blood flow to parts of the body, and typically used by people with angina or heart failure. Would it have provided her with an unfair advantage? Well, who knows. It was the epitome of the grey area between legal and illegal doping.

While meldonium is now illegal in competition, there are many other pharmaceutical products that remain legal in competition, but occupy a murky performance-enhancing middle ground.

In cycling, painkiller tramadol has been one of the most commonly discussed, apparently used by cyclists for pain reduction and performance gains. It was initially banned by pro teams who are part of the MPCC (Mouvement Pour Cyclisme Crédible), and in 2019 the UCI stepped in to ban its use across the board. It doesn’t stop there, though.

Stimulants such as nicotine and caffeine are a constant focus of concern, and both are now on the WADA (World Anti-Doping Authority) Monitored Substance list – a halfway house to becoming banned, and with good reason.

Using prescription medicine has a risk of side-effects, and there often isn’t any real advantage. Let’s start with the painkillers.

‘Tramadol is an opiate like morphine and ketamine and those sorts of drugs,’ explains Dr Jarrad van Zuydam, doctor for UAE Team Emirates (although he was at Dimension Data at the time of our interview).

‘It is weaker but has the psychotropic side-effects of those drugs: dizziness, light-headedness, concentration and it affects your reaction times. There’s no evidence to show that it makes you go faster.’

Painkillers on the whole, he says, have little benefit but a strong risk factor – even Ibuprofen can cause serious kidney damage if used in competition. I put that lot on my ‘no’ list.

Van Zuydam is just as disparaging about the other side of the spectrum – stimulants. This group includes psychoactive drugs that will temporarily increase mental and physical performance. Amphetamines, cocaine and MDMA fall into this category, but so do legal substances such as caffeine and nicotine.

‘The stimulants are quite a nasty group,’ van Zuydam warns. ‘Even caffeine in high doses can be quite toxic, potentially setting off heart arrhythmias.’

While regular coffee drinkers may be shocked at the suggestion that caffeine is a big risk, it should be remembered the athletes tend to take it in pill form, and in large doses.

As such, I decide that caffeine is worth a try, but determine to keep the doses small.

The list of dubious legal performance aids doesn’t end there, though. Other substances favoured by athletes include drugs that act as vasodilators (such as meldonium), increasing the flow of blood.

Closely related are the bronchodilators (salbutamol), which increase the flow of air into the lungs. Then there are synthetic hormones (levothyroxine), which increase certain hormones for performance enhancing purposes.

These greyest of substances, while legal in the eyes of WADA, require a prescription in the UK, so I decide to leave these out of my tests.

But there are performance enhancers that are much less risky and more freely available.


Pills and powders: What legal substances can you take to improve performance?

Supplements come in many forms and some can enhance performance. Dietary supplements, which are the most common, are used to top up trace elements that occur in a normal diet – magnesium, zinc or iron for instance.

For pro cyclists this is an important part of maintaining performance.

‘The UCI recommends and regulates that you do blood tests during the year. If for instance you are low on iron, which is important for your performance, you do a follow-up and you make sure the athletes go back to normal levels,’ explains Judith Haudum, nutritionist for BMC Racing. After consultation, I put a magnesium supplement on my ‘yes’ list, as a deficiency would seriously hinder the effects of the rest of my cocktail of products.

A more interesting group of supplements are those that fall into the ‘ergogenic’ class and are aimed purely at enhancing performance.

‘There are two that spring to mind,’ says Matt Furber, senior scientist at GSK Human Performance Lab. ‘Creatine, which works on your phosphocreatine pathway to increase strength, power and the regeneration of that explosive power.

'Then you’ve got beta-alanine, which buffers lactate production. So they may increase your performance through greater regeneration or greater power.’

Both creatine and beta-alanine are naturally occurring in food, but in small quantities.

‘You hear people say, “We try to do it all through food.” I’ve heard Team Ineos say that as well. But there’s no way you’re going to get 20g of creatine a day just through food,’ said Rob Child, who was performance biochemist at Team Katusha and Elite Sport Group when we spoke back in 2016.

‘To take these things in an efficacious dose, the quantity of meat needed would suppress the appetite so much you wouldn’t be able to eat the carbohydrates you need.’

With that in mind, it’s no surprise that both beta-alanine and creatine supplements are present in the pro peloton. 'I would say maybe one-third of our riders use beta-alanine,’ says Haudum.

She’s far more disparaging about creatine, though: ‘Nobody [at BMC] uses creatine. When you look into the science and into the papers you can see that there’s not really much evidence for road cycling.

'If you go on the track then ;it would be a good supplement to use.’ Van Zuydam explains that it was present but uncommon among his athletes at Dimension Data.

‘You use it for very specific reasons, perhaps if it’s in the pre-season where you’ve got a sprinter or a big guy who’s trying to put on a bit of muscle mass.

'During the season, creatine is probably not the best idea, as it just gives you extra weight, extra water and extra muscle mass.’ Other ergogenic supplements include HMB, an amino acid that prevents muscle protein breakdown, and L-carnitine, which reduces fatigue and helps convert fats into energy.


A hasty high: Choosing supplements for our own journey

Ergogenic supplements are not a quick fix, and take some time to bring about real-world improvements. There are immediate boosters, though, of which bicarbonate of soda is the most unusual.

Bicarbonate of soda increases the body’s levels of naturally occurring bicarbonate, which is an alkali chemical that fights the effects of lactic acid in the muscles. It is definitely not as risky as painkillers or stimulants, but it does leave doctors concerned.

‘Bicarb is one of those traditional ones, it’s been used by cyclists for a long time,’ says van Zuydam.

‘They use it for short efforts – prologues and time-trials – but increasingly the research is showing that it’s not all that beneficial. It also has some gastrointestinal side effects – diarrhoea, vomiting and things like that.’

Another supplement to naturally occurring chemicals are ketones, which have become the most sensationalised supplement in sport.

‘A ketone is another energy source,’ says Kieran Clarke, professor of physiological biochemistry at Oxford University, and inventor of the first ketone-based drink, DeltaG. Clarke’s discovery has excited the cycling world a great deal, and rumours have spread that bottles of ketone drink have been sold for €2,000 (£1,500) each to pro cyclists.

A ketone is normally metabolised by the body to create energy, and originates from fat.

‘It’s produced normally when you haven’t eaten or when you’re on a ketogenic diet,’ Clarke says.

‘The research was originally funded by the US army. They wanted somebody to invent a really efficient food and we said we could do that.’ The drink created by Clarke means that you can put ketones straight into your body that can be turned into energy.

‘It has similar effects to glucose and it works in the same way as glucose drinks, it provides energy for your muscles.’ Ketones certainly piqued our interest, but still await approval for sale in the UK. However, the hype seems somewhat unjustified.

Their inventor, Professor Kieran Clarke, sees no real advantages for the average athlete over glucose supplements and drinks. ‘If you have glucose by itself or ketones by itself, it’s not superior. It’s exactly the same – it’s just providing energy. For sprints glucose is better actually, because you need something that’s anaerobic,’ she says.

Rumours have circulated that athletes enjoy a 10% instant advantage at threshold pace when drinking a ketone ester, but when we put the claims to Clarke, she responds with restrained laughter: ‘No, I don’t think so! I think anyone who thinks that is having themselves on.’

Armed with some expert advice, I now have my final list of products to test. Making the cut is beta-alanine, creatine, HMB, magnesium and L-carnitine, all of which I will take over a six-week period.

For an occasional instant boost, I’ll try bicarbonate of soda and caffeine. Remember, I’m not a pro rider or a sports scientist, and this is no peer-reviewed journal.

I can only take the products, do the tests and tell you what effects I find. So here goes…


The programme

I follow a schedule suggested by Rob Child that’s designed to load certain elements such as creatine, but build up more slowly with others such as beta-alanine.

My first discovery is that taking supplements is a chore. My programme includes four beta-alanine tablets, 20g of creatine in four doses (reducing to 5g after the loading period), three HMB tablets, 400mg of magnesium and an L-carnitine tablet.

That’s 14 supplement doses each day. It’s the sort of medical schedule usually reserved for the very ill or very old.

From the outset, there are effects, both good and bad. Beta-alanine is probably most noticeable. It creates a tingling in the skin, a type of pins and needles, which is technically called paraesthesia. It’s harmless, but unsettling.

The creatine leaves me feeling dehydrated and I frequently wake up in the night thirsty. The L-carnitine and magnesium are unnoticeable. The HMB has a strong taste, which means it is best taken with food.

In terms of effects, the creatine kicks in quickly. Normally my weight is unwaveringly stable, but over my six weeks of creatine I put on half a kilo. My jeans feel tighter and my quads feel more powerful.

With my daily dose of magnesium I feel like I have more energy, more concentration and less fatigue, while the effects of beta-alanine and HMB are too subtle to tell. But I do think my speed of recovery is constantly increasing.

When it comes to caffeine and bicarbonate of soda, I only need to take them once to feel the effects. Having experimented with caffeine before, and been a little unsettled by the impact on my nerves and heartbeat, I approach the dosage conservatively, siding for only 100mg – many athletes take as much as 500mg for competition.

It is enough to have me bouncing off the walls. The bicarbonate of soda, meanwhile, is truly foul. I can only compare it to drinking brine from a fish tank, with the scaly, fishy bits included.

For six weeks I put up with the inconvenience and occasional discomfort of filling my body with these legal performance enhancers. The only question that remains is whether they have had any measurable effect on my abilities as a cyclist.


The data drop: What differences legal doping made

During the course of the programme, I noticed only the subtlest of differences during my regular rides.

I was a little less fatigued after long distances. My short sprints were ever so slightly sharper. My long, threshold climbing efforts were much the same – my legs felt a little more powerful but also a little heavier. They were also quick to fatigue but quick to recover.

Going by sensation alone, I’d say the results were noticeable although minimal. Would the numbers from my tests in the lab agree?

Rob Child developed a ramp test for me, performed on a static bike, and monitored readings for heart rate, power and blood lactate. I did the test at the beginning of the six weeks and at regular points during the programme, and now I’m back to see if my final readings are any different to the first.

VO2 max CO2

Peter Stuart undergoing physiological testing

The test durations within the ramp test are 10 seconds, 30 seconds, one minute, five minutes and 20 minutes, and I’m forced to empty myself on the bike until I’m a crumpled mess in a pool of my own sweat.

Once it’s over and Child has had a chance to analyse the results, he tells me the extent of my transformation into a cycling superman. (Full results available to see here).

Duration Baseline (av. watts) Week 3 Week 5* Week 6
10 seconds 795 750 802 886
30 seconds 592 608 621 686
1 min on/off/on 502/441 541/475 526/466 538/475
5 minutes 372 370 378 376
20 minutes 323 325 ** 313

*Caffeine and bicarb of soda used for this test **We skipped the 20-minute component of this test as we wanted to focus on shorter efforts

‘The 30-second power showed the most marked and consistent increase relative to baseline, increasing by 2.7% at week three, 4.8% at week five and 16% at week six,’ he says.

‘For this type of effort fatigue is caused by a drop in muscle ATP and the accumulation of metabolic acids, so this may reflect the dual effects of creatine and beta–alanine supplementation.

'The one-minute power tests also improved consistently by around 7.7% after three weeks, 5% at five weeks and 7% at six weeks.’

My five and 20-minute efforts are eerily similar to the initial test results. ‘The five and 20-minute tests place a bigger emphasis on oxygen uptake, transport and utilisation,’ Child says.

‘As creatine and beta-alanine have little if any effect on aerobic energy production they may have limited value for increasing performance for longer efforts.’

I’m happy to see my shorter efforts improve, but I’m a little surprised not to see my wattage jump up by bigger margins. Van Zuydam had speculated as much when he told me at the beginning of the programme, ‘My bet is that it’s not going to make much of a difference to your performance. Supplements have their place, but that place is only after you take care of the basics.’

With the test complete, I’m left with the choice of continuing with supplements or returning to life ‘paniagua’, without supplements.

While creatine did give me more power, it added weight I didn’t need, and had side-effects on my hydration I didn’t want. Caffeine and bicarb also affected me in concerning ways, without big enough gains to compensate. Perhaps L-carnitine or HMB had an effect on recovery, but I’ll see if I miss them before returning to my box of pills.

From my own experiences, anecdotes from other riders and scientific journals, I believe beta-alanine is possibly cycling’s best legal performance enhancer, and I’ll continue to use it. Magnesium, too, will stay in my armoury, simply because I feel better taking it than not.

So can a cyclist dope legally? Of course, but there are risks and sacrifices to be made to do so, and only for the slightest of gains – certainly nothing to compare to the grand margins that illegal drugs would seem to offer.

I leave the experiment having strengthened some of the weakest facets of my form, but more aware than ever that no performance gains come for free.

Many thanks to Etixx (Magnesium, Carnitine and HMB) and PowerBar (Creatine and Beta-Alanine) for providing nutritional and ergogenic supplements, as well as Garmin and Wattbike for all power testing equipment.

This article first appeared on in May 2016, and was updated in March 2020


Legal doping: The data

A detailed break-down of Cyclist’s legal doping investigation test data

Baseline test - 26.2.2016

Base lactate 1.6mml

Lactate at rest: 1.6mmol/L

Weight: 72.0 kgs

10 seconds Average Max
Power 795w 1,001w
Heart rate 127bpm 137bpm
30 Seconds Average
Power 592w
Heartrate 152bpm
Lactate 9.5mmol/L
60 Seconds Average
Power 502w
Heartrate 168bpm
Lactate 8.1mmol/L
60 seconds Average
Power 441w
Heartrate 174bpm
Lactate 12.9mmol/L
5 minutes Average
Power 372w
Heartrate 168bpm
Lactate 14.6mmol/L
Lactate @50w 10.2mmol/L
20 minutes Average
Power 323w
Heartrate 166bpm
Lactate 19.5mmol/L
Lactate @50w 10.2mmol/L

Test 2 – After 3 weeks 18.3.2016

Base lactate 1.5mml

Lactate at rest: 1.5mmol/L

Weight: 72.4kgs

10 seconds Average Max
Power 583w 909w
Heart rate 90bpm 109bpm
30 Seconds Average
Power 608w
Heartrate 133bpm
Lactate 8.1mmol/L
60 Seconds Average
Power 541w
Heartrate 150bpm
Lactate 9.0mmol/L
60 seconds Average
Power 475w
Heartrate 161bpm
Lactate 14.4mmol/L
5 minutes Average
Power 370w
Heartrate 169bpm
Lactate 14.6mmol/L
Lactate @50w 10.2mmol/L
20 minutes Average
Power 325w
Heartrate 173bpm
Lactate 16.5mmol/L

Test 3* with 150mg Caffeine and 15g of bicarbonate soda - After 5 weeks 7.4.2016

10 seconds Average Max
Power 802w 933w
Heart rate 136bpm 1148bpm
30 Seconds Average
Power 621w
Heartrate 160bpm
60 Seconds Average
Power 526w
Heartrate 164bpm
60 seconds Average
Power 466w
Heartrate 172bpm
5 minutes Average
Power 378w
Heartrate 175bpm

*This test excluded lactate analysis or the 20-minute block, as it was intended to find the short-term effect of caffeine and bicarbonate soda

Test 4 - After 6 weeks 11.4.2016

Base lactate 2.0mml

Weight: 72.6kgs

10 seconds Average Max
Power 886w 975ww
Heart rate 131bpm 144bpm
30 Seconds Average
Power 686w
Heartrate 155bpm
Lactate 9.4mmol/L
60 Seconds Average
Power 538w
Heartrate 160bpm
Lactate 11.4mmol/L
60 seconds Average
Power 475w
Heartrate 173bpm
Lactate 15.3mmol/L
5 minutes Average
Power 374w
Heartrate 176bpm
Lactate 14.6mmol/L
Lactate @50w Test error
20 minutes Average
Power 313w
Heartrate 179bpm
Lactate 11mmol/L
Lactate @50w N/A


Rob Child, performance biochemist for Team Katusha and Elite Sports Group (

The test

The most popular lab tests for cyclists are VO2 max and lactate threshold, which involve the rider progressively increasing power output to reach threshold, or exhaustion.

Such progressive changes in workload rarely (if ever) occur in racing, where riders typically make supra maximal efforts of varying durations and also undertake sustained efforts above anaerobic threshold. To reflect this, a range of exercise durations was chosen for the tests.

VO2 max threshold

These typifying the type of efforts that would occur in a road race especially for key moves such as finishing sprints, breakaways and bridging gaps. Therefore the test battery provides a more useful insight into how these supplements might benefit real world cycling performance.

The supplements

A range of supplements were chosen based on their ability to increase performance during high intensity exercise. These products were all screened for stimulants and steroids to ensure that any performance effects observed were not due to banned substances.


This was loaded over 5 days, with a maintenance dose to maintain muscle creatine phosphate levels over the remainder of the study.

Creatine can improve high intensity exercise performance by maintaining muscle ATP levels, and thereby delaying the onset of fatigue. It can also increase the speed of recovery between maximal efforts by generating ATP more quickly.


This is taken up into the muscle and converted to carnosine, an acid buffer. Supplementation with beta-alanine over 6 weeks significantly increases muscle carnosine and is associated with improved performance when fatigue is caused by a fall in muscle ph i.e. accumulation of metabolic acids.

This can be a cause of fatigue in efforts lasting 30 seconds up to 20 minutes.


The results were assessed relative to the baseline pre supplementation condition. The 10-second effort measures muscle activation and muscle mass.

The drop in power at weeks 3 and 5 probably reflects test variability and questions if the 5% increase in 10 second power at week 6 is real, or just variability in the data.

The 30-second power showed the most marked and consistent increase relative to baseline, increasing by 2.7% at week 3, 4.8% at week 5 and 16% at week 6.

For this type of effort fatigue is caused by at drop in muscle ATP and the accumulation of metabolic acids, so this may reflect the dual effects of creatine and beta–alanine supplementation.

The 1-minute power tests also improved consistently by around 7.7% after 3 weeks, 5% at 5 weeks and 7% at 6 weeks. Again the likely cause of fatigue is lowered muscle ATP and muscle acidosis.

Comparing the power output for the first and second 1-minute test on each lab visit allows the speed of muscle recovery to be assessed.

At each lab visit muscle power was around 13% lower for the second 1 minute compared to the first, suggesting that although the supplements may have increased power output they did not help the muscle recover more quickly.

For the 5 minute test improvements in power was 0% week 3, 1.6% at 5 weeks and 1% at 6 weeks, which are small and within the range of experimental error.

Similarly the performance drop of 3% for the 20-minute test may reflect experimental error. Unlike the 10-second, 30 second and 1 minute tests the 5 and 20-minute tests place a bigger emphasis on oxygen uptake, transport and utilization.

As creatine and beta-alanine have little if any effect on aerobic energy production they may have limited value for increasing performance for longer duration efforts.