Sports supplements that actually work: the evidence-based guide (2026)

By Ramon Curto · Updated 4 August 2026

Most sports supplements are noise: plausible mechanisms with far less proof than advertising suggests. A short list is useful, but only for the right event, dose and athlete. Caffeine and carbohydrate can support competition; creatine and protein usually help through training and recovery.

Food, sleep, progressive training and tested race fuelling come first. Supplements cannot repair low energy availability, poor sleep, unsuitable training or an undiagnosed deficiency. These are specific tools, not a compulsory daily stack.

Costs are broad, not recommendations. They are rounded from August 2026 Spanish retail snapshots for energy/endurance and athlete health; spend varies with body mass, races and pack size.

The starting map is the Australian Institute of Sport Sports Supplement Framework: Group A products have strong evidence for specific sporting situations, Group B options are emerging or context-dependent, Group C lacks persuasive benefit and Group D is prohibited or high risk. We then checked ISSN position stands, the IOC consensus and peer-reviewed systematic reviews or meta-analyses.

The tier describes confidence in a defined use, not a universal prescription. One small sponsored trial cannot establish a general effect, and statistical significance may not deliver a worthwhile race gain. Sources were checked on 2026-08-04; total evidence outranked brand claims, with no first-person experimentation used as proof.

Creatine increases intramuscular phosphocreatine, helping regenerate ATP during hard efforts. It is not marathon fuel, but can support strength training, repeated sprints, surges and finishing speed. AIS guidance supports 3–5 g daily; loading about 0.3 g/kg/day for five days is optional. Without it, stores rise over roughly four weeks.

Take plain monohydrate consistently; timing is secondary. It suits endurance athletes who lift, sprint or repeat high-power efforts. A possible early 1–2 kg water gain matters before weight-sensitive goals, while divided loading can limit stomach upset. It offers no acute race-morning effect. Kidney disease, pregnancy, medication or other health concerns require professional advice.

Caffeine reduces perceived effort and raises alertness through adenosine-receptor antagonism. The ISSN stand finds consistent endurance benefit at 3–6 mg/kg; more is not better, and some respond below 3 mg/kg. A conventional plan is 45–60 minutes pre-start, while gum and in-race doses act differently.

It suits runners, cyclists, triathletes and HYROX athletes who rehearse the dose. Sensitivity varies. Risks include anxiety, tremor, gut upset, raised heart rate and poor sleep; AIS guidance notes a roughly five-hour half-life. Never copy a dose, combine sources blindly or debut it on race morning. Adolescents, pregnancy and cardiovascular, anxiety or medication concerns require professional guidance.

Carbohydrate maintains blood glucose and supplies muscle as internal stores become limiting. It has exceptionally clear endurance evidence. AIS gel guidance recommends 30–60 g/hour for 1–2.5-hour events and up to 90 g/hour from multiple transportable carbohydrates beyond roughly 2.5–3 hours. Short hard events may benefit from mouth sensing.

Start early and distribute doses instead of waiting for a crash. It suits prolonged running, cycling, triathlon and long HYROX preparation, not every easy session. Risks are gut distress and poor fluid matching. Train the gut, count carbohydrate grams, take concentrated gels with suitable water and use the fuelling planner before race week.

Protein supplies essential amino acids for tissue remodelling and repair; powder is only convenient food. The ISSN stand places most exercising adults at 1.4–2.0 g/kg/day across three to five meals. About 20–40 g, or 0.25–0.4 g/kg, per meal is practical, not a compulsory shake schedule.

It helps athletes with high loads, low appetite, plant-based diets or difficult recovery logistics. Those meeting the target through meals gain little from extra powder; AIS guidance prioritises food. Healthy food-first athletes need no powder. Excess can displace carbohydrate, fibre and variety; milk products may cause symptoms. Kidney disease or a prescribed low-protein diet requires clinical advice.

Dietary nitrate becomes nitrite and then nitric oxide, potentially improving vascular and muscular efficiency. The AIS protocol uses 6–8 mmol, about 350–500 mg, two to three hours pre-exercise. Several-day loading is possible; antibacterial mouthwash can blunt oral conversion.

Gains are small and variable, most relevant to hard 4–30-minute efforts and less elite athletes. It may suit a 5K, time trial or intense segment, not guarantee an ultra gain. Pink urine or stools are harmless; gut discomfort can occur. Low blood pressure or nitrate medication requires professional guidance. Choose a standardised nitrate dose, not an unspecified drink, and rehearse it first.

Sodium bicarbonate raises extracellular buffering, helping remove hydrogen ions during severe glycolytic work. The ISSN stand supports 0.2–0.3 g/kg, chiefly for intense 30-second to 12-minute efforts and repeated bouts. Taking it 120–180 minutes pre-exercise with a carbohydrate-rich meal can improve tolerance.

It is more relevant to cycling pursuits, hard finishes or repeated HYROX stations than steady mileage. It offers no steady-effort benefit. Nausea, diarrhoea, bloating and vomiting can erase any gain, so individual testing and split or encapsulated protocols matter. The sodium load makes casual use unsuitable with hypertension, kidney, heart or medication concerns. Never debut it on race day.

Beta-alanine raises muscle carnosine, an intracellular buffer for sustained high-intensity work. The ISSN stand supports 4–6 g/day for at least two to four weeks; practical protocols reach 6.4 g/day in four 1.6 g doses with meals. This is chronic loading, not an acute pre-workout.

Benefits are most plausible for one-to-four-minute efforts, repeated intervals and hard 30-second to 10-minute blocks. That matters in track, cycling attacks and HYROX, not directly in a marathon. Long loading also demands reliable long-term adherence. Tingling is the dose-related side effect; smaller divided or sustained-release doses reduce it. Low-intensity-only athletes have less reason to buy it.

Sodium helps retain fluid and replace sweat losses; it neither prevents every cramp nor becomes safer at higher doses. AIS guidance uses roughly 0.5–0.7 g sodium per litre as a starting range, individualised by sweat, duration, climate and drinking access.

It is useful for long events, heat, heavy or salty sweaters and rapid rehydration. Short cool sessions rarely require supplements. Estimate loss with the sweat-rate calculator, then rehearse. Drinking beyond losses can cause dangerous exercise-associated hyponatraemia even with electrolytes. Hypertension, kidney or heart disease and sodium-related prescriptions rule out aggressive targets without professional oversight.

Collagen supplies glycine, proline and hydroxyproline for connective tissue. Early studies are encouraging, but clinical outcomes remain uncertain. AIS guidance suggests 20 g 40–60 minutes before tendon-loading exercise. It may complement clinician-designed rehab or high-impact training, not replace progressive loading, adequate energy or protein. It offers no acute analgesia. Gut symptoms and cost are practical downsides; injury management belongs with a professional.

Tart cherry polyphenols may modestly influence oxidative stress, soreness and recovery. The AIS protocol describes products equivalent to 90–200 cherries daily for 4–7 days before and 2–4 days after a demanding event. Evidence is heterogeneous: use a short intervention, not permanent antioxidant cover. Concentrates add carbohydrate and may cause gut or laxative effects. It is more defensible around damaging competition than normal training.

EPA and DHA affect cell membranes and inflammatory signalling, without a reliable endurance-performance gain. AIS guidance notes possible physiological and recovery effects but insufficient consistency. Start with oily fish; if intake is low, 0.5–1 g/day combined EPA+DHA with a meal is reasonable, while 1–2 g/day is sometimes used short term under guidance. Reflux and gut symptoms occur, and high doses may interact with anticoagulants. It is not race fuel.

Iron supports oxygen transport; deficiency harms health and endurance, while extra iron cannot improve normal status. The AIS protocol describes 100 mg elemental iron daily or on alternate mornings for 8–12 weeks, then retesting under medical supervision. Runners, menstruating athletes, vegetarians and altitude athletes may warrant screening, not self-prescribing. Constipation, nausea and overload are risks; ferritin, haemoglobin, symptoms and context should guide treatment.

Vitamin D supports bone, muscle and immune function, but supplementation makes sense when testing shows low status. AIS guidance gives 2,000 IU vitamin D3 daily for one to two months, followed by retesting. Indoor training, little sun and winter increase risk. Chronic excess can cause hypercalcaemia and kidney harm; normal-status athletes should not expect a race gain.

BCAA provide three amino acids, while repair requires all essential amino acids. The AIS conclusion finds little justification for isolated BCAA with adequate quality protein. A laboratory marker can change without better racing or recovery. Buy food or complete protein instead.

Glutamine has biological and clinical roles, but no established ergogenic effect in healthy endurance athletes. A meta-analysis found no overall benefit for aerobic performance, body composition or immune outcomes. Routine performance tubs are low priority; therapeutic use is a separate medical question.

These blends combine stimulants, extracts and unclear doses. The NIH review finds limited or unconvincing evidence for many ingredients and flags interactions, side effects and contamination. They cannot replace an energy plan and may worsen sleep, heart-rate control and fuelling. Avoid them, especially in tested sport.

Tribulus, DHEA-like products and hormone blends lack persuasive performance evidence. AIS Group D identifies prohormones and boosters as prohibited or high risk; contamination adds danger. No evidence-based endurance dose exists. A legal-looking label does not guarantee anti-doping safety.

Match caffeine to the start. For a 07:00 race, a rehearsed dose usually falls around 06:00–06:15; an evening dose may impair sleep. Long cyclists or triathletes may prefer less pre-start and a later top-up. Count coffee, gels, gum and drinks together.

Carbohydrate follows duration and gut tolerance: 30–60 g/hour for a half marathon, Olympic triathlon or comparable event; progress toward 60–90 g/hour for marathons, long rides and long-course triathlon. HYROX usually needs a simpler plan. Build it with the fuelling planner, then compare lactate gels: science and price.

In heat, sodium belongs inside a fluid plan, never beside unlimited drinking. Start from sweat loss, conditions and drink access; heavy salty sweaters may need more than a cool-weather 10K runner. Find an event in the running calendar or triathlon calendar, then rehearse the schedule.

No supplement is contamination-proof. Undeclared substances or cross-contamination can produce an adverse finding, while strict liability makes athletes responsible for what enters their body. Check the current WADA Prohibited List and Sport Integrity Australia guidance.

When use is justified, prefer an exact batch listed by Informed Sport or NSF Certified for Sport. Certification reduces risk; it neither proves efficacy nor permits a prohibited ingredient. Keep the invoice, batch number and packaging.

Minors, pregnancy or breastfeeding, medication, and kidney, liver, cardiovascular, gastrointestinal, metabolic or mental-health conditions require a physician or sports dietitian first. Deficiency treatment, high sodium and aggressive caffeine or bicarbonate especially need individual assessment.

Creatine mainly supports a runner's strength, repeated sprints, hills and finishing speed, not steady-distance fuel. Take 3–5 g/day consistently if those goals matter. Possible early water-mass gain means testing it well before a weight-sensitive race, not during race week itself.

Caffeine works for many adults at 3–6 mg/kg, usually 45–60 minutes pre-exercise. Start lower because response and side effects vary, and total every source. Late starts need caution: caffeine's long half-life may improve racing while compromising sleep and subsequent recovery.

Most training adults cover adaptation and repair with 1.4–2.0 g/kg/day total protein across three to five meals. Powder is optional convenience, not a superior nutrient. High-load or energy-restricted phases may need sports-dietitian adjustment rather than simply adding automatic extra shakes.

BCAA are three amino acids, not complete recovery. With adequate protein and essential amino acids, isolated BCAA show no convincing extra endurance or recovery benefit. Complete food or protein is the rational purchase; a claim about muscle signalling does not equal better performance.

A multivitamin is broad insurance, not a performance enhancer, and cannot precisely correct an unknown problem. Athletes with a varied adequate diet rarely need one. Restricted diets, symptoms or suspected deficiency call for assessment and targeted testing because unnecessary high doses can harm.

Yes. A legal-looking supplement may contain an undeclared prohibited substance or manufacturing contamination. Strict liability still applies. Use only a justified product, verify its exact batch through a recognised programme, retain details and check medications and ingredients against current anti-doping resources.

No. Electrolytes help when duration, heat, high loss or salty sweat creates a replacement need. Water and meals cover many short, cool sessions. Estimate sweat rate, avoid drinking beyond losses and individualise sodium instead of following a universal capsules-per-hour rule.

Sources were checked on 4 August 2026. SportPlan will review this guide annually, or sooner if the AIS framework, an ISSN position stand, anti-doping rules or a major synthesis changes the consensus. Price links are market snapshots only and never product endorsements.

• AIS Sports Supplement Framework
• AIS Group A
• AIS Group B
• AIS Group C
• AIS Group D: prohormones and hormone boosters
• IOC consensus statement on supplements and the high-performance athlete
• AIS creatine guidance
• ISSN position stand: caffeine
• AIS caffeine timing guidance
• AIS sports gels and carbohydrate targets
• ISSN position stand: protein and exercise
• AIS isolated-protein guidance
• AIS beetroot juice and nitrate guidance
• ISSN position stand: sodium bicarbonate
• ISSN position stand: beta-alanine
• AIS electrolyte guidance
• AIS collagen-support guidance
• AIS fruit-polyphenol guidance
• AIS fish-oil and omega-3 guidance
• AIS iron guidance
• AIS vitamin D guidance
• AIS BCAA consensus
• Meta-analysis of glutamine supplementation
• NIH fact sheet: dietary supplements for weight loss
• NIH fact sheet: supplements for exercise and athletic performance
• WADA Prohibited List
• Sport Integrity Australia: supplements in sport
• Informed Sport batch-testing programme
• NSF Certified for Sport
• Spanish retail price snapshot: energy and endurance
• Spanish retail price snapshot: athlete health