Pre-Race Nutrition Supplements: What Actually Works

Race morning nutrition talk always circles back to the same question: what can I actually take that will make a measurable difference? Between caffeine, beetroot juice, bicarb, and newer names like Nomio and CurraNZ hitting athlete's kit bags, there's no shortage of options and no shortage of marketing claims to match. This one's about separating what the peer-reviewed evidence actually supports from what's just a good Instagram ad, so you can build a pre-race protocol based on physiology, not hype.

Table Of Contents

• Caffeine: The Old Reliable

• Dietary Nitrates: Beetroot Juice And The Nitric Oxide Pathway

• Sodium Bicarbonate: Buffering The Burn

• Nomio: The Broccoli Sprout Shot

• CurraNZ: New Zealand Blackcurrant Extract

• The Key Takeaway

Caffeine: The Old Reliable

Caffeine remains the most researched ergogenic aid in sport, and for good reason. Its main mechanism isn't metabolic - it's neurological. Caffeine competitively blocks adenosine receptors in the central nervous system, which blunts perceived exertion and helps you push harder for the same "feel" of effort ¹. Where it gets interesting is the individual variability side: genetic differences in how you metabolise caffeine (via the CYP1A2 gene) mean some athletes respond brilliantly and others barely at all, which is exactly why caffeine should always be trialled in training, never for the first time on race day ². It's legal, sitting only on WADA's monitoring program rather than the banned list ³.

Recommended Dose → The standard evidence-based dose is 3-6mg/kg body mass, taken around 60 minutes pre-race to line up with peak plasma levels ⁴. Lower doses of 1-3mg/kg still work, just to a smaller degree, providing a genuine option for athletes who are caffeine-sensitive, get GI or anxiety side effects at higher doses, or simply want a smaller, more predictable hit. 

Talk Nerdy To Me
A 60-minute pre-race dose of 3-6mg/kg caffeine competitively blocks adenosine A1/A2A receptors in the CNS, blunting perceived exertion enough to shave ~2.2% off endurance time-trial performance in a meta-analysis of 46 RCTs - a margin that regularly separates podium places⁵. A 2025 dose-response meta-analysis found that 1-3mg/kg produced a statistically significant improvement in time-trial performance (SMD-0.27), roughly half the effect size seen at 4-6mg/kg (SMD-0.52) ⁶.

• 150-200mg Caffeinated Products → Science In Sport (SIS) Beta Fuel Energy Gel + Nootropics, Rhise Performance Fuel, Styrkr Gel3 Dual-Carb Energy GelCaffeine+, Fixx Nutrition Coldbrew Coffee Shot 50ml

• 70-100mg Caffeinated Products → Maurten Gel 100 Caf 100, Honey Stinger Energy Gel Salted Caramel Latte (Caffeinated), Precision Fuel & Hydration PF 30 Caffeine Gel, PURE Sports Nutrition Race Energy Gels

Dietary Nitrates: Beetroot Juice And The Nitric Oxide Pathway

Beetroot juice works through the nitrate-nitrite-nitric oxide pathway: oral bacteria convert swallowed nitrate to nitrite, which is then converted to nitric oxide in low-oxygen conditions like working muscle ⁷. The payoff is a genuine reduction in the oxygen cost of exercise - your muscles get more efficient at turning oxygen into ATP, which is a different mechanism to how caffeine or bicarb work ⁸.

Recommended Use →Effective dosing sits around 5-9mmol nitrate (roughly 300-600mg), taken 2-3 hours pre-race - in practice, that's:

• 1x Beet It Sport 400

• 1x Science In Sport (SIS) GO Nitrate Shot

• 1x PURE Sports Nutrition Performance + Race Ready sachet

• 1x serve of PURE Sports Nutrition Beet Endurance

A short 2-3 day loading protocol often produces slightly better results than a single acute dose ⁹.  One practical detail that trips people up: antibacterial mouthwash kills the oral bacteria needed for the first conversion step, so skip the minty mouthwash around dosing ¹⁰. Worth noting too that the benefit tends to be more pronounced in recreational and moderately trained athletes than in elite endurance athletes, who already operate close to peak efficiency ¹¹.

Talk Nerdy To Me
Beetroot juice doesn't just "boost stamina" - it measurably lowers the ATP cost of muscle contraction, letting trained muscle produce the same force for less oxygen ⁸.

Sodium Bicarbonate: Buffering The Burn

Sodium bicarbonate - "bicarb loading" - works on pH, not oxygen delivery. During hard anaerobic efforts, hydrogen ions build up in the muscle and drop pH, contributing directly to fatigue. Raising blood bicarbonate concentration steepens the gradient that pulls those hydrogen ions out of the muscle faster, delaying the burn ¹². It's best suited to efforts in the roughly 1-10 minute range, or repeated high-intensity surges within a longer race - think a hard finishing kick or a series of hill accelerations - rather than steady-state pacing itself ¹³.

Recommended Use →The evidence-backed dose is 0.2-0.4g/kg body mass, taken 1-3 hours out, though gastrointestinal distress (bloating, cramping, urgency) is common enough that a serial-loading protocol over a few days, or newer enteric-coated capsules, are often used to reduce the GI hit ¹⁴,¹⁵

Talk Nerdy To Me
A single 0.3g/kg dose of sodium bicarbonate raises blood pH enough to meaningfully delay fatigue in 1-10 minute efforts - but for a meaningful share of athletes, that same dose triggers GI distress severe enough to end the effort early, which is why protocol-testing in training is non-negotiable ¹²,¹⁴.

Nomio: The Broccoli Sprout Shot

Nomio is a different animal entirely from the three aids above - it's a concentrated broccoli sprout shot, delivering isothiocyanates (ITCs) in a dose roughly equivalent to 2.5-3kg of raw broccoli. Rather than buffering pH or boosting oxygen efficiency, ITCs activate the Nrf2 pathway, the body's internal antioxidant defence system, which is proposed to blunt oxidative stress and support recovery from repeated hard training ¹⁶. The research base is real but genuinely early: a double-blind, placebo-controlled crossover trial out of Sweden (Karolinska Institutet and the Swedish School of Sport and Health Sciences) found reduced oxidative stress markers and improved time-to-exhaustion over seven days of intense training, and a newer study specifically found reduced blood lactate during submaximal exercise ¹⁶,¹⁷. The catch is sample size - both studies sit in the 9-15 participant range, so treat this as promising early-stage evidence rather than an established, caffeine-level ergogenic aid.

Recommended Use → A common protocol is one shot the night before (before bed) plus a second around 3 hours pre-race - practical guidance rather than a tested protocol, and not intended for daily, long-term use.

Talk Nerdy To Me
Nomio's isothiocyanates work through Nrf2 pathway activation rather than pH buffering or oxygen economy - a genuinely novel mechanism among ergogenic aids, though the human evidence behind it currently comes from crossover trials of only 9-15 participants, so the magnitude of any real-world race-day benefit is still being established ¹⁶,¹⁷.

CurraNZ: New Zealand Blackcurrant Extract

CurraNZ is a standardised New Zealand blackcurrant extract, dosed at 300mg (105mg anthocyanins) per capsule. Its proposed mechanisms are broader than a single pathway: anthocyanins appear to support nitric oxide-mediated blood flow, shift substrate use toward fat oxidation during submaximal exercise, and act as antioxidants that may reduce exercise-induced muscle damage ¹⁹. In trained cyclists, seven days of daily dosing improved ¹⁶.1 km time-trial performance by 2.4% and lifted fat oxidation by around 27% at moderate intensity, versus placebo ¹⁸. It's caffeine-free, generally well tolerated, and - for athletes who need batch-tested products - available in an Informed-Sport certified form.

Recommended Use → The standard protocol is 1 daily tablet for about a week pre-event, continued on race day, with some evidence it also supports faster strength recovery after muscle-damaging efforts ²⁰.

Talk Nerdy To Me
A week of daily New Zealand blackcurrant extract (300mg, 105mg anthocyanins) lifted 16.1km cycling time-trial performance by 2.4% and boosted fat oxidation by 27% during submaximal exercise in trained cyclists - a result that holds up alongside, and in this trial exceeded, caffeine's published effect size ¹⁸,¹⁹.

The Key Takeaway

None of these five aids do the same job, which is exactly why they're not interchangeable:

• Caffeine and CurraNZ are best suited to sustained endurance efforts, where perceived exertion and fuel use matter most.

• Beetroot juice earns its place through genuine oxygen-cost efficiency, with the biggest wins for moderately trained athletes rather than elite ones.

• Sodium bicarbonate is a tool for the hard, short, high-intensity moments within a race - not steady pacing.

• Nomio is the newest and least-established of the group: interesting mechanism, small trials, worth watching rather than banking on.

• Across all five, the same rule applies: trial dose, timing, and tolerance in training long before race day.

• No ergogenic aid fixes a fuelling or hydration strategy that isn't already dialled in - they sit on top of the foundations, not in place of them.

Ash Miller
Dietitian and Nutritionist (Masters)
Bachelor of Physical and Health Education
Instagram: @ashthomo_nutrition

References

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2. Pickering C, Kiely J. Are the current guidelines on caffeine use in sport optimal for everyone? Sports Med. 2018;48(1):7-16.

3. Diel P. Caffeine and doping - what have we learned since 2004. Nutrients. 2020;12(8):2167.

4. Guest NS, VanDusseldorp TA, Nelson MT, et al. International society of sports nutrition position stand: caffeine and exercise performance. J Int Soc Sports Nutr. 2021;18(1):1.

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6. Martins GL, Aparecido JM, Marquezi ML, et al. Dose-response effect of oral caffeine use on aerobic exercise performance: a systematic review and meta-analysis. Nutrients. 2025;18(12):1989.

7. Jones AM. Dietary nitrate supplementation and exercise performance. Sports Med. 2014;44(Suppl 1):S35-S45.

8. Bailey SJ, Winyard P, Vanhatalo A, et al. Dietary nitrate supplementation reduces the O2 cost of low-intensity exercise and enhances tolerance to high-intensity exercise in humans. J Appl Physiol. 2009;107(4):1144-1155.

9. Lansley KE, Winyard PG, Bailey SJ, et al. Dietary nitrate supplementation reduces the O2 cost of walking and running. J Appl Physiol. 2011;110(3):591-600.

10. Kapil V, Haydar SMA, Pearl V, Lundberg JO, Weitzberg E, Ahluwalia A. Antibacterial mouthwash blunts oral nitrate reduction and increases blood pressure in treated hypertensive men and women. Am J Hypertens. 2015;28(5):572-575.

11. Hlinský T, Kumstát M. Effects of dietary nitrates on time trial performance in athletes with different training status. Nutrients. 2020;12(9):2734.

12. Carr AJ, Hopkins WG, Gore CJ. Effects of acute alkalosis and acidosis on performance: a meta-analysis. Sports Med. 2011;41(10):801-814.

13. de Oliveira LF, Dolan E, Swinton PA, et al. Extracellular buffering supplements to improve exercise capacity and performance. Sports Med. 2022;52(3):505-526.

14. Grgic J, Pedisic Z, Saunders B, et al. International Society of Sports Nutrition position stand: sodium bicarbonate and exercise performance. J Int Soc Sports Nutr. 2021;18(1):61.

15. Hilton NP, Leach NK, Craig MM, Sparks SA, McNaughton LR. Enteric-coated sodium bicarbonate attenuates gastrointestinal side-effects. Int J Sport Nutr Exerc Metab. 2020;30(1):62-68.

16. Flockhart M, Nilsson LC, Tillqvist EN, et al. Glucosinolate-rich broccoli sprouts protect against oxidative stress and improve adaptations to intense exercise training. Redox Biol. 2023;67:102873.

17. Vinge F, et al. Effects of a glucosinolate-rich beverage on blood lactate concentrations during submaximal exercise. Physiol Rep. 2026. doi:10.14814/phy2.71081.

18. Cook MD, Myers SD, Blacker SD, Willems ME. New Zealand blackcurrant extract improves cycling performance and fat oxidation in cyclists. Eur J Appl Physiol. 2015;115(11):2357-2365.

19. Braakhuis AJ, Somerville VX, Hurst RD. The effect of New Zealand blackcurrant on sport performance and related biomarkers. J Int Soc Sports Nutr. 2020;17(1):25.

20. Hunt JEA, Coelho MOC, Buxton S, et al. Consumption of New Zealand blackcurrant extract improves recovery from exercise-induced muscle damage. Nutrients. 2021;13(8):2875.

Disclaimer:

The content in this blog is for general information only and is not a substitute for professional medical advice, diagnosis, or treatment. Always speak with your doctor or allied health team before changing your diet, exercise, or taking supplements, especially if you have a health condition or take medication. Please use this information as a guide only. Aid Station doesn't take responsibility for individual outcomes.