Evidence. Context. Practical Use.
Compare protein, creatine, pre-workouts, recovery products and other popular fitness supplements by their evidence, practical uses, limitations and safety considerations.
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Supplements can fill a dietary gap or improve a defined performance outcome, but none replaces a well-designed workout plan, adequate calories and protein, sleep or medical care. Evidence varies sharply between ingredients and products: creatine monohydrate, adequate protein and caffeine have clear use cases, while BCAAs, glutamine, fat burners and testosterone boosters are often overmarketed.
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Showing all 21 supplement guides.
Protein powders provide a convenient way to reach daily protein targets when normal food is impractical. Whey, casein, soy, pea, rice and blended products can all support muscle growth and recovery when total protein and resistance training are adequate; the powder itself is not superior to a suitable meal.
View Protein GuideCreatine monohydrate has the strongest evidence among general sports supplements for improving repeated high-intensity performance, strength and training-supported lean mass. A daily 3–5 g maintenance dose is widely used, while loading is optional; newer creatine forms have not shown a consistent advantage over monohydrate.
View Creatine GuideBCAA supplements supply leucine, isoleucine and valine, but they do not provide all essential amino acids required for a complete muscle-protein response. When daily intake already contains enough high-quality protein, separate BCAAs usually add little for muscle growth, performance or recovery.
View BCAA GuidePre-workout supplements are mixtures rather than one proven formula. Acute benefit usually depends on disclosed, effective doses, most commonly caffeine, while ingredients such as creatine and beta-alanine work through regular use. Compare labels carefully and avoid excessive stimulants or proprietary blends that conceal doses.
View Pre-Workout GuidePost-workout supplements are convenience products for supplying protein, carbohydrate or electrolytes when a normal meal is delayed or rapid recovery is required. The right formula depends on the previous meal, sweat loss and time before the next session; no universal recovery shake or narrow anabolic window applies to everyone.
View Post-Workout GuideFat burner supplements cannot replace a sustained calorie deficit. Caffeine may slightly increase alertness and energy expenditure, but most thermogenic, appetite-control and green-tea-extract products produce small or inconsistent effects and can introduce stimulant, liver, medication-interaction or contamination risks.
View Fat Burners GuideGlutamine is abundant in the body and has important roles in nitrogen transport, intestinal tissue and immune cells. In healthy, well-fed lifters, however, supplemental glutamine has not shown a reliable additional benefit for muscle gain, strength, soreness or routine post-workout recovery.
View Glutamine GuideTestosterone booster formulas commonly combine herbs, vitamins and minerals, but evidence for meaningful increases in testosterone, strength or muscle mass in healthy men with normal levels is limited and ingredient-specific. Correcting a genuine nutrient deficiency can help; persistent symptoms require medical assessment rather than a proprietary blend.
View Testosterone GuideFish oil provides the long-chain omega-3 fats EPA and DHA and can be useful when oily-fish intake is low. Evidence is strongest for selected cardiovascular uses, while effects on joint comfort and exercise recovery vary; high doses can interact with anticoagulant treatment and should not be assumed harmless.
View Fish Oil GuideBeta-alanine raises muscle carnosine when taken consistently and may improve repeated high-intensity efforts lasting roughly 30 seconds to 10 minutes. It is not an acute stimulant or direct muscle builder; split daily dosing is commonly used because larger servings can cause temporary tingling.
View Beta-Alanine GuideWeight gainer powders combine protein with large amounts of carbohydrate and sometimes fat, making them useful for people who struggle to eat enough calories. They do not create muscle without progressive training, and oversized servings can turn a modest surplus into unnecessary fat gain.
View Weight Gainer GuideHMB is a leucine metabolite studied for muscle preservation and recovery. Its most plausible value is in older, untrained, immobilised or highly catabolic populations; trained lifters already eating enough protein often see smaller or inconsistent benefits, so it is not a core bodybuilding supplement.
View HMB GuideL-carnitine helps transport fatty acids within cellular energy metabolism, but that biological role does not make oral supplementation a reliable fat burner. Exercise-performance and body-composition findings are mixed, with potential benefits dependent on the population, supplement form, dose and duration.
View L-Carnitine GuideBetaine is found in foods such as beetroot, spinach and whole grains and also functions as an osmolyte and methyl donor. Small trials report mixed or modest effects on strength, power and body composition, so it remains an optional performance supplement rather than a high-priority choice.
View Betaine GuideCoenzyme Q10 contributes to mitochondrial energy transfer and acts as an antioxidant. Supplementation has established clinical uses in some contexts, but exercise-performance and recovery results in healthy active adults are mixed; medication use and underlying health should guide the decision.
View CoQ10 GuideCaffeine can acutely improve alertness, endurance and some repeated-effort, strength or power outcomes, although response varies. Lower doses may be sufficient, and late or high intake can worsen sleep, anxiety, heart-rate symptoms and recovery; total intake from coffee, energy drinks and pre-workouts must be counted.
View Caffeine GuideCollagen peptides may support skin and connective-tissue outcomes and can improve joint symptoms or selected tendon adaptations when combined with training. Collagen is low in essential amino acids and should not replace whey, soy, meat, dairy or another complete protein when muscle protein synthesis is the priority.
View Collagen GuideElectrolyte supplements are most useful during prolonged exercise, heat exposure, heavy sweating or rapid turnaround between sessions. Sodium is usually the main mineral lost in sweat; water and normal meals are sufficient for many gym workouts, and electrolyte products do not prevent every muscle cramp.
View Electrolytes GuideZMA combines zinc, magnesium and vitamin B6. Replacing a genuine deficiency can support normal physiology, but ZMA has not shown a reliable additional effect on testosterone, strength, muscle growth or sleep in athletes whose nutrient intake is already sufficient.
View ZMA GuideAshwagandha extracts may produce small improvements in perceived stress or sleep, and some trials report strength-related effects, but products, doses and study populations vary. It can cause gastrointestinal effects, affect thyroid function, interact with medicines and has been linked to rare liver injury.
View Ashwagandha GuideNitric oxide booster products often contain citrulline, arginine or dietary nitrate. Citrulline and nitrate may improve blood flow or selected exercise outcomes in some settings, but results are dose- and task-dependent; arginine is less consistently effective, and a larger muscle pump does not guarantee greater hypertrophy.
View Nitric Oxide GuideSupplements work best after training, nutrition and recovery are organised. Compare the workout plans, use the nutrition guide to set calories, protein and hydration, and record progress with the workout trackers.