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Top 8 sports supplements for triathletes

Sports nutrition can enhance training adaptations and race performances, but only if you choose the right ones. Here are the best supplements for improving athletic performance…

Best sports supplements for athletes

They say you are what you eat so, for an athlete, that means natural carbohydrates, quality protein sources, good fats, and a variety of vitamin-rich fruit and veg should be the mainstay of your daily diet.


And while sports nutrition supplements should never be a substitute for a healthy nutrition plan – which starts with a good shopping list and eating habits – there are scientifically measured results elicited by using the appropriate sports nutrition.

Popular supplements for triathletes

In some cases, just one use of a supplement can result in performance improvements of 2-5%, with even greater benefits if you’re a good responder. And if the effects of these supplements accumulate over multiple training sessions and races, it’s clear that this could be a very worthwhile use of both time and money.

Sports nutrition used correctly can provide a significant ergogenic advantage, and at a smaller cost than many of the triathlon products on the market today. Take it from me, sports nutrition is the last 5% icing on the proverbial performance cake. So, in no particular order, here are 8 of the best sports supplements around today…

1. Creatine Monohydrate

Emerging in the ’90s, this supplement promised increased power and strength for explosive events, shorter triathlons (sprints) and resistance training – it’s claimed to speed up muscle recovery. Creatine, as creatine monohydrate (CM), increases naturally occurring creatine-phosphate in muscle stores, which aids high energy output; in particular sprinting and weight training.

According to one study, CM use can also improve lactate tolerance during strenuous exercise, though it’s worth noting that impacts of long-term use of this and similar supplements aren’t known. Although endurance athletes have been sceptical, according to research those involved in strength training on a vegetarian or low red meat diet and those looking to increase power could benefit from relatively short-term use of CM. This isn’t a supplement many athletes shout about, though I’m aware of age-groupers and pros who take it effectively.

Opinion: A short-term loading regime can help re-stock muscle stores and help during strength and interval training. When I was vegetarian it helped improve my strength practically overnight.

Relevant to: Those seeking strength and lean mass gains but who are committed to training hard in order to achieve it.

Optimum dose: Slow-load (preferred): 5g per day, with 20-30g carbohydrate for approx one month. Fast load: 4 x 5g per day for 5-7 days.

Top deal: Applied Nutrition Creatine Monohydrate

Optimised for pre-workout and used by athletes, this creatine monohydrate powder comes from a familiar brand. Simply add 5g of Applied Nutrition’s powder to water and shake.

2. Carb and protein recovery

These claim to accelerate glycogen storage into fatigued muscles, enhance endurance and stimulate lean muscle gain.

As far back as 1992, studies have shown that taking a recovery drink (112g carb plus 40g protein) boosted glycogen stores. Since then, further studies have found that smaller doses work but only in the first four to six hours. Despite these results, not all experts agree the combination enhances endurance, though there are no obvious negatives to small doses of protein during training (for example, 3-10g/hr).

More recent data suggests taking a recovery drink prior to or during resistance or endurance training can help create a more anabolic, ‘positive’ muscle recovery environment. However, you have to be training hard or long for these to be relevant. Rego Recovery was made famous by Chris Boardman, who used it when recovery drinks were in their infancy.

Opinion: These work for hard resistance training, high-intensity interval sessions and post-race.

Relevant to: Improver and top age-groupers, when training hard and regularly.

Optimum dose: Approximately 35-60g carbohydrate plus 15-25g protein.

Top deal: High5 Recovery Drink

High5’s protein recovery drink contains 18g whey protein and 37g carbohydrate (dextrose, maltodextrin and fructose) per 60g serving, which works out at 27 servings per tub for £1.55 per drink.

Whey protein’s what you’re looking for in a recovery drink as it’s loaded with muscle-repairing amino acids and digests far quicker than casein protein. This is important to maximise protein synthesis, which is at its highest for two hours after exercise.

See our full review of the High5 Recovery Drink for more.

3. Caffeine

Caffeine has a huge amount of scientific support to suggest it can, in modest doses, significantly improve performance and endurance. It’s purported to increase the ability to tolerate high-intensity training and race-day performances by making the athlete more alert and/or indefatigable. It does this in several ways, most significantly by blocking the binding of adenosine to its receptors, meaning athletes can do harder interval sessions or go longer when the body would otherwise be fatigued.

Products with caffeine include pre-workout drinks, gels and bars, and are best used in sessions or races that demand a peak performance. Caffeine is of little use if a controlled, short-to-moderate distance is your goal.

The drawbacks of using caffeine too often include a potential psychological dependence, an inability to sleep if used too late in the day and the risk of masking fatigue, which should be a sign to ease up on training. Unfortunately, around 10% of athletes have a genetic predisposition to
be unresponsive to caffeine.

Opinion: One of the cheapest and simplest training and racing boosters.

Relevant to: Long-distance sessions or races and HIT (High Intensity Training) sessions.

Optimum dose: 3mg/kg one hour before HIT, or multiple smaller doses at regular intervals in long races or sessions.

Top deal: Revvies Energy Strips

Caffeine’s the most proven ergogenic in the legal medical cabinet with its benefits of burning more fat, increased focus and greater power output. That’s why these strips are on solid scientific footing. They only contain 40mg caffeine but they’re designed to top up pre-exercise levels. They dissolve on the tongue for faster absorption.

Reviewed in 220 Triathlon issue 387.

4. Carbohydrate feeding

Carbohydrate drinks, gels and bars claim to enhance endurance, improve hydration and speed recovery. Scientifically speaking the moment you start a training session, carbohydrates are being used as fuel. So forget the TV ‘shockumentaries’ dispelling sports drinks, you need carbohydrate sources such as sports drinks, gels and bars to fuel sessions. You can use natural sources such as bananas, dried fruit and so on, but they’re often less convenient. Plus, carbohydrate sports nutrition products deliver easy-to-absorb carbohydrates that exceed the amounts found in natural sources. They can also feature added ergogenics, such as caffeine.

Opinion: Without doubt carbohydrate sources work to deliver fuel in training and make race-day fuelling easier.

Relevant to: All triathletes but not in all sessions. Can be used for pre-race hydration, in races and everyday training, especially over 60mins.

Optimum dose: Needs to be matched to your size and training session needs, so between 30-80g per hour of training or racing with sufficient water (500-800ml).

Top deal: SiS Beta Fuel

Beta Fuel’s been around for a while, but only in powder form. The orange gel we reviewed in our best energy gels test is made of a newly developed blend of maltodextrin to fructose in a 1:08 ratio, which delivers a hefty 40g of carbs. SiS’s studies identified this split as optimum, increasing the percentage of oxidised carbs from 62% to 74%. We can’t verify that without a lab, but the texture and taste is great, and it digests smoothly.

5. Sodium phosphate

Claimed to increase maximum oxygen uptake and enhance lactate tolerance. Early studies into sodium phosphate loading in the 90s found significant increases in VO2max and improved time-trial performance. This was thought to be due to increased levels of 2,3-DPG in red blood cells, which off-loads more oxygen at the working muscle. Repeated studies show regular improvements in VO2 max of 5% and above with sodium phosphate use, with power increases in cycle tests of 9-15 watts at threshold. UK studies have also reported gains in time-trial performance of 2-3secs per mile of racing in a short load-up.

One rather inconvenient drawback with its usage is that it may be associated with gastric issues, so as with any new supplement, try this out extensively in training before race week. Few names have been put to this particular approach of supplementation but I’m aware of top triathletes and cyclists using it.

Opinion: It requires a consistent daily regime in race week and therefore forward planning, but it works very well and costs little.

Relevant to: Top 25% of the field looking for that race-day 3% advantage.

Optimum dose: Six days with 4 x 1g doses spread evenly across each day, starting six to seven days before your big race.

6. Nitric Oxide

Increasing levels of nitric oxide (NO) through eating foods high in nitrate is reported to reduce blood pressure, improve exercise tolerance and increase efficiency of movement. Research in this area, notably from Exeter University, found that consuming foods high in nitrate – such as beetroot juice – naturally increases NO levels in the blood, which leads to reduced oxygen use during exercise of any intensity (anything from walking to heavy cycling). Studies, including ones testing beetroot juice with the nitrate removed to act as the perfect placebo, have shown improved performance effects of between 1-3%.

As with many supplements, some athletes fail to respond, but it’s a cheap suck-it-and-see test that’s worth a try. Pro athletes and cycling teams such as Sky already incorporate nitrate-rich foods and drinks into their diets.

Opinion: Simple and natural addition to your diet, but beetroot will turn your urine pink and may affect some people’s bowels if concentrated forms or high doses are used.

Relevant to: Those looking to improve their health by drinking or eating more veg (for example, beetroot, spinach, celery and leek) and wanting to boost speed and efficiency.

Optimum dose: 6mmol of nitrate. For example, 500ml beetroot juice daily for six days before an event. The BEET IT product provides 0.3g nitrate per 7cl shot.

7. Beta Alanine

Beta alanine (BA) is claimed to buffer lactate and increase endurance by raising muscle carnosine levels, though this is an emerging area so its optimal use has yet to be established. Some studies show increased lean mass gains from resistance training when it’s combined with creatine (see p61). A recent analysis of several studies found a 2.8% average effect with 179g BA loading in efforts of 60secs to 4mins plus. The downside to BA is ‘flushing’, that can occur on the face and hands, though this is transient and not known to be harmful. Ironman elite Andy Potts appears alongside BA adverts.

Opinion: This is very top end and not for those who can’t handle some short-term flushing. See BA as an added bonus.

Relevant to: Elite racers with the very best of everything already in place.

Optimum dose: See packet instructions as various optimal doses are recommended (from 24-90 days).

8. L-Carnitine

L-Carnitine (LC) supplements have been claimed to increase fat burning and aid endurance. Carnitine exists in the muscle naturally, and is involved in shuttling energy into the muscles’ aerobic engines, known as mitochondria. I knew about LC 20 years ago and advised elite Ironman athletes of the day on how to use it, resulting in plenty of anecdotes about its efficacy. In 2012 a study proved that using carbs to spike insulin levels while co-ingesting LC could pump up LC stores by 20% over six months. The resulting 55% drop in glycogen use, 44% drop in lactate and reduced stress on the metabolism backed up what we already thought. With more precise loading, athletes have already reported great effects in both recovery and long-distance racing ability.

Opinion: It’s an expensive regime but correct use brings very effective top-end results.

Relevant to: Top-end Ironman athletes or short-course athletes looking to accelerate recovery from long or hard sessions.


Optimum dose: 1-2g, twice a day, taken with carbs. Take it, for example, with a high carb breakfast and lunch.