A guide to sports supplements for athletes

As an athlete, you’ve probably come across sports supplements. Powders, gels, capsules, pills – the list goes on, and with it, a certain amount of marketing and confusion.

Now, using some supplements in the right way may benefit you as an athlete. But others have potential to harm your health, performance, and reputation (if they violate antidoping rules). The IOC recommends athletes undergo a complete nutritional assessment before deciding whether to use supplements [1].

The thing is, incorporating sports supplements into your routine takes a considerable effort and expertise. How do you know which sports supplement is best? When should you take them? And how do you know if you even need a supplement in the first place? We answer these questions and help you find the right supplement to suit your goals in our guide to sports supplements for athletes.

We’ll cover:

• What are sports supplements?
• What are the different types of sports supplements?
• What’s the difference between sports and dietary supplements?
• Do sports supplements actually work?
• Best sports supplements for muscle growth
• Best sports supplements for recovery
• Best sports supplements for hydration
• Best sports supplements for endurance
• How to know if you actually need sports supplements

What are sports supplements?
 

Throughout history, athletes have tried weird and wonderful things in the hope of getting a cut above the rest - cyclists in the 1800s even took substances that would probably land you in rehab or jail today.

Thankfully, things have moved on a bit since then. Sports supplements are consumables designed to improve athletic performance, whether through speeding up recovery, boosting endurance, or building more muscle.

They’re basically a concentrated version of stuff you could get from whole foods – it’s just that as an athlete you would need to consume a lot of these whole foods to get the quantities supplied in a supplement.

Additionally, sports supplements come in a more convenient format.

What are the different types of sports supplements?
 

The Australian Institute of Sport (AIS) has helpfully categorised supplements into four different groups according to their effectiveness and safety.

Group A

These supplements have been researched and tested, and there is strong scientific evidence that they may have some effect on performance.

Group A supplements include:

• Creatine
• Caffeine
• β-alanine
• Electrolytes
• Bicarbonate
• Beetroot juice

Group B

Supplements in group B need a bit more research. This means that they may have some enhancing properties, but the research isn’t robust enough for it to be backed up by science.

Group B supplements include [8]:

• Antioxidants
• Carnitine
• Collagen
• Ketone supplements
• Pre- and probiotics

Group C

Group C supplements have no robust science behind them and possibly won’t be worth taking as you are likely not to see any beneficial effects. The AIS explains that if you can’t find the supplement you are taking in Group A or Group B, then it probably deserves to be in Group C.

Group C supplements include [9]:

• Magneisum
• Alpha Lipoic Acid (ALA)
• Β-hydroxy β-methylbutyrate (HMB)
• Branched-chain amino acids (BCAA)
• Phosphate

Group D

Finally we have group D, supplements that are banned in sports, potentially harmful to your health, and could result in a positive doping test. We would strongly recommend that you avoid anything in group D.

These substances are on the list for a reason, and you should question whether you want to put these in your body.

Group D supplements include [10]:

• Stimulants such as ephedrine, strychnine, and sibutramine
• Prohormones and hormone boosters including DHEA and androsenedione
• GH releasers and “Peptides”
• Beta-2 agonists
• Selective androgen receptor modulators (SARMS)
• Metabolic modulators

What’s the difference between sports and dietary supplements?
 

While sports supplements are designed to optimise your training and recovery, the goal of dietary supplements is to cover deficiencies in minerals and vitamins that are missing from your diet.

Dietary supplements include nutrients such as:

• Magnesium
• Vitamin D
• Omega-3
• Iron

A deficiency in vitamins and minerals can leave you with several unwanted symptoms that could be affecting your performance. But if you are eating a well-balanced diet, there is no reason why (other than a health condition) you should need to supplement most nutrients. The exception is vitamin D, which we can only get from sunlight (and small amounts from fish and eggs). The NHS recommends everyone in the UK supplement between October to March.

You can read more about creating a supplement routine that works for you in our blog.

Do sports supplements actually work?
 

It can be a bit of a minefield in the supplement world. Although they can come in pill form, supplements aren’t as rigorously regulated as pharmaceuticals, and are classified as foods. Unlike medicines, food supplements generally don't have to demonstrate their effectiveness in clinical trials before being sold. However, UK regulations still govern their safety, labelling and the health claims manufacturers can make. This doesn't guarantee that every product works, or that every product on sale complies with the rules.

Why is this important?

At best you could be wasting your money on a product that does nothing for your performance. And at worst, you could be putting your health or sporting career at risk, studies suggest between 10% and 30% of supplements may contain banned substances or ingredients not listed on the label [6].

Some tips for picking a good quality sports supplement:

• Stick to proven ingredients (more on that below) and always buy from reputable brands.
• Look for third party testing – in the UK Informed Sport are the leading banned-substance testing control.
• Choose products that list active ingredients and exact quantities – look for salt forms such as magnesium citrate or iron (bis)glycinate, and specific milligram amounts instead of proprietary blends.
• If the claims seem too good to be true, they probably are – a supplement alone can’t get you shredded or help you beat your PB, and if you can't trust what's on the outside of the packet, you may not want to trust what's on the inside too.

So, now you know how to choose a decent supplement, let’s explore which ones are best for your needs.

Best sports supplements for muscle growth
 

First up: muscle mass. If building muscle is your goal, two supplements stand out – protein and creatine. On their own these supplements won’t do much, but combined with a decent training programme can lead to results.

Protein

We have a whole blog about the benefits of protein, so we’ll just give you the basics here.

Protein is made up of amino acids, and these provide your muscles the building blocks they need to repair after training. Most active people benefit from around 1.2–2.0g of protein per kilogram of body weight per day, spread across meals – roughly 20–40g per sitting.

Now, you can absolutely hit your target from meat, fish, eggs, dairy, tofu and legumes. But a protein shake can be a handy way to top up your intake if you're busy, training hard or eating a plant-based diet.

What to look for in protein supplements:

• Whey protein is fast-digesting and rich in leucine, the amino acid that switches on muscle building.
• Casein digests more slowly, and blends of pea and rice protein are good plant-based options.

When is the best time to take protein?

Your total daily protein intake is what’s most important. Having some within a couple of hours of training, and a serving before bed can support proper muscle recovery, while, anecdotally, many swear by a protein-rich breakfast to keep appetite levels and mood steady throughout the day.

Creatine

Creatine is one of the most researched supplements around – it’s one of the few that actually work. Evidence shows it improves strength, power, and muscle gain when combined with a training plan.

When you take creatine, it binds with a phosphate group to create phosphocreatine, which the body can then use to support ATP production. You can read more about creatine in our blog.

What to look for in a creatine supplement:

• Creatine monohydrate is the most studied form of creatine.
• Reputable brand, rather than expensive price tag

When is the best time to take creatine?

Consistency is more important than timing for creatine, although a recent review suggested taking it post-workout may have extra benefits [1]. It’s important to note creatine can cause an increase in water weight, as it makes your muscles retain water. This is perfectly normal, and doesn’t mean you’ve gained fat or muscle mass.

How much creatine should I take?

Most research suggests using 3–5g a day. Some people start with a higher ‘loading’ dose for 5–7 days, but this isn’t necessary because you’ll reach the same muscle levels after about a month at 3–5g a day. Creatine monohydrate is safe for healthy adults at these doses.

Then consistency is key.

Best sports supplements for recovery
 

Recovery is where the supplement aisle gets crowded – and where the evidence starts to get a little shakier.

Prioritising proper sleep, incorporating rest days, and properly fuelling your body will do much more for your recovery than any supplement. With this in mind, here are some products you may come across.

Branched-chain amino acids (BCAAs)

BCAAs are a group of three essential amino acids.

They are:

• Leucine
• Isoleucine
• Valine

You’ll often see them marketed for recovery and reducing muscle soreness.

Amino acids are the building blocks of protein. There are 20 in total, and nine of these are considered essential, meaning you can only get them from diet. That’s all very well, but you already get BCAAs from protein-rich foods and protein powders, and research suggests they offer little extra benefit if you're already eating enough protein [2]. For most people, a whey or plant protein shake is a better-value choice.

Magnesium

Ok, so magnesium is technically a dietary supplement rather than one specific to sports. But you’ll most certainly come across it when searching for recovery supplements, so it’s worth a mention here.

Magnesium does have functions in muscle contraction, energy production and sleep, and athletes can lose small amounts through sweat.

However, there's limited evidence that supplementing improves recovery if you already have healthy levels – remember magnesium is in group C in the supplements list. You can get all the magnesium you need from food sources such as leafy greens, nuts and seeds, and wholegrains.

Best sports supplements for hydration
 

 When you sweat you lose water from your body, but you also lose minerals such as sodium, potassium, and magnesium. These ions are known as electrolytes, and they help to control everything from nerve signals to muscle contraction.

Electrolytes are another one of those supplements having a marketing craze – many influencers start their morning with daily electrolytes. While in most cases a sip of electrolytes won’t do you any harm, the reality is food and water should supply you with all you need.

If you do want to get electrolytes, check the mineral balance on the label for how much each serving supplies.

How do I know if I need electrolytes?

So, when do you actually need electrolytes?

There’s a few instances:

• After exercising for 60 minutes or longer, especially if intense
• Sweating heavily during exercise
• Working out in humid or extremely hot conditions
• If you are a “salty sweater”, resulting in white residue on your clothes after workouts

Symptoms of dehydration include [5]:

• Feeling thirsty
• Headache and feeling light-headed
• Dark yellow, strong-smelling pee
• Peeing less often than usual
• Feeling dizzy or lightheaded
• Feeling tired
• Dry mouth, lips and tongue
• Sunken eyes

Best sports supplements for endurance
 

Whether you're training for a marathon or trying to last longer in the final set, two supplements have good evidence for helping you go harder for longer: carbs, caffeine and beta-alanine.

Carbs

Carbohydrate supplements are a go-to for endurance athletes taking part in long-distance competitions. They help you maintain blood sugar levels, delay muscle fatigue, and regulate glycogen storage.

How do you use carbs for endurance?

Approximately 30-60g of carbs per hour is recommended for endurance exercise lasting 1-2.5 hours, with up to 90g per hour for longer events and those trained athletes who can tolerate

Caffeine

Caffeine is one of the most effective legal performance boosters available. It reduces how hard exercise feels and can improve endurance, power and focus.

How much caffeine do you need for endurance?

Research typically uses around 3-6 mg per kilogram of body weight (about 200mg for a 70kg person, or 2-3 espressos), taken 30–60 minutes before exercise. Higher doses don't tend to bring extra benefits, but they do bring more side effects. Coffee, caffeine gels and tablets all work. Alternative sources of caffeine such as caffeinated chewing gum, mouth rinses, energy gels and chews have been shown to improve performance, primarily in aerobic exercise. Energy drinks and pre-workout supplements containing caffeine have been demonstrated to enhance both anaerobic and aerobic performance [4].

Caffeine affects people differently. Too much can cause jitters, an upset stomach, a racing heart and poor sleep, so avoid it late in the day and always test it in training before using it in a race.

Healthy adults are advised to stay under 400mg a day, and 200mg if pregnant. Speak to your GP if you have a heart condition or high blood pressure.

β-alanine

β-alanine, or beta-alanine, is an amino acid that boosts the levels of carnosine in your muscles, helping buffer acidic ions that build up during intense exercise. It's most useful for high-intensity efforts lasting roughly one to four minutes, such as rowing, middle-distance running, HIIT and combat sports [3].

How do you take beta-alanine for endurance?

Beta-alanine works by building up in your muscles over time, so daily use is key. Studies suggest using 3–6g a day, split into smaller doses, for at least four weeks, and report the best results occur after 10–12 weeks [3].

Beta-alanine can cause a harmless tingling sensation on the skin (paraesthesia). Splitting the dose or using a slow-release product can help.

Do I need a sports supplement?
 

There is a time and place for supplements in sports and only a select few may be beneficial, and none are guaranteed to work.

When looking to supplement, context is important. Ask yourself:

• Why are you supplementing?
• Will it benefit the exercise I am doing?
• Is there anything else to consider?
• What are my individual needs?

Remember it is never a case of the more, the better – you could risk hurting yourself (along with your pride and bank balance). The one thing that is guaranteed to give you the highest chance of success is yourself – the harder you push the more you will gain.

---

References

1. Maughan RJ, Burke LM, Dvorak J, Larson-Meyer DE, Peeling P, Phillips SM, et al. IOC consensus statement: dietary supplements and the high-performance athlete. Br J Sports Med. 2018;52(7):439–455. doi: 10.1136/bjsports-2018-099027
2. Ribeiro F, Longobardi I, Perim P, Duarte B, Ferreira P, Gualano B, et al. Timing of creatine supplementation around exercise: a real concern? Nutrients. 2021;13(8):2844. doi: 10.3390/nu13082844
3. Wolfe RR. Branched-chain amino acids and muscle protein synthesis in humans: myth or reality? J Int Soc Sports Nutr. 2017;14:30. doi: 10.1186/s12970-017-0184-9
4. Trexler ET, Smith-Ryan AE, Stout JR, Hoffman JR, Wilborn CD, Sale C, et al. International society of sports nutrition position stand: beta-alanine. J Int Soc Sports Nutr. 2015;12:30. doi: 10.1186/s12970-015-0090-y
5. Guest NS, VanDusseldorp TA, Nelson MT, Grgic J, Schoenfeld BJ, Jenkins NDM, et al. International society of sports nutrition position stand: caffeine and exercise performance. J Int Soc Sports Nutr. 2021;18(1):1. doi: 10.1186/s12970-020-00383-4
6. NHS. Dehydration [Internet]. NHS; 2026 [cited 2026 Oct 23].
7. Jagim AR, Harty PS, Erickson JL, Tinsley GM, Garner D, Galpin AJ. Prevalence of adulteration in dietary supplements and recommendations for safe supplement practices in sport. Front Sports Act Living. 2023;5:1239121. doi: 10.3389/fspor.2023.1239121
8. Australian Institute of Sport. Group B [Internet]. Canberra: Australian Sports Commission; [cited 2026 Oct 23].
9. Australian Institute of Sport. Group C [Internet]. Canberra: Australian Sports Commission; [cited 2026 Oct 23].
10. Australian Institute of Sport. Group D [Internet]. Canberra: Australian Sports Commission; [cited 2026 Oct 23].