Supplements

1. Supplementspreliminary · human dataAdded 26 July 2026

   Caffeine helped women's performance in every cycle phase

   A meta-analysis of 20 randomised trials in women found acute caffeine gave a small average performance boost (Hedges' g = 0.37), with positive estimates in every menstrual-cycle phase and in contraceptive users, and no clear evidence that phase changes the effect. Certainty was low to very low.

   ⚠What it shows: Systematic review and meta-analysis of 20 randomised trials with 144 effect sizes in women; risk-of-bias concerns, sparse subgroup data, inconsistent verification of menstrual phase and low-to-very-low GRADE certainty mean subgroup conclusions are hypothesis-generating only.Systematic review · Front Nutr

   Full breakdown →Caffeine guide →Caffeine Half-Life Calculator →Acute caffeine ingestion and exercise performance in women: a systematic review and meta-analysis of menstrual-cycle phase and hormonal contraceptive status. Front Nutr 2026
2. Supplementswell supported · human dataAdded 26 July 2026

   Caffeine sharpened sprints, not jumps or strength

   Across 13 randomised placebo-controlled trials in rugby players, acute caffeine produced small improvements in sprint performance and lower perceived exertion, plus a large but highly heterogeneous effect on passing accuracy. Jumping, strength, metabolic and hormonal markers showed no significant change.

   ⚠What it shows: Systematic review and meta-analysis of 15 studies (13 in the pooled analysis) in rugby players, but GRADE certainty was low to very low, and the passing-accuracy result showed high heterogeneity and possible small-study effects.Systematic review · Front Nutr

   Full breakdown →Caffeine guide →Caffeine Half-Life Calculator →Acute caffeine supplementation in rugby players: a systematic review and meta-analysis of physical performance, sport-specific performance, perceptual responses, and physiological markers. Front Nutr 2026
3. Supplementswell supported · human dataAdded 26 July 2026

   Daily multivitamin nudged memory in older adults

   In the 573-person clinic subcohort of the COSMOS trial, a daily multivitamin-mineral supplement produced a more favourable two-year change in episodic memory than placebo (0.12 SD units) but no clear benefit for executive function or attention. Pooling three COSMOS cognitive substudies, the multivitamin improved global cognition by 0.07 SD units, an effect the authors equate to reducing cognitive ageing by 2 years.

   ⚠What it shows: Meta-analysis of three cognitive substudies (n=573, 2158 and 2472) nested within the single COSMOS trial of adults aged 60 and over, so it is not independent replication; effects were small in size, tests differed between substudies, and no effect was seen on executive function or attention in the clinic subcohort.Meta-analysis · Am J Clin Nutr

   Full breakdown →Executive function explained →Effect of multivitamin-mineral supplementation versus placebo on cognitive function: results from the clinic subcohort of the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial and meta-analysis of 3 cognitive studies within COSMOS. Am J Clin Nutr 2024
4. Supplementspreliminary · human dataAdded 26 July 2026

   Ketone drink stretched time to exhaustion in the heat

   Endurance-trained men who took a ketone monoester with caffeine before 90 minutes of loaded treadmill work in 34 °C heat lasted longer in a subsequent time-to-exhaustion test than on carbohydrate, and scored better on the easier working-memory task. Harder cognitive tests, heart rate and core temperature were unchanged.

   ⚠What it shows: One randomised double-blind crossover trial in 17 endurance-trained young men with high VO2max; benefits appeared on some cognitive measures but not others, and the time-to-exhaustion difference was under two minutes on a short high-intensity test.RCT · J Int Soc Sports Nutr

   Full breakdown →Executive function explained →VO2max Calculator →Ketone monoester ingestion and cognitive and physical performance during exercise-heat stress. J Int Soc Sports Nutr 2026
5. Supplementspreliminary · human dataAdded 26 July 2026

   Cordyceps sharpened reaction time, not peak oxygen use

   Twelve recreationally active young men who took 1 g of Cordyceps militaris extract 30 minutes before a maximal cycling test had faster Stroop reaction times after exercise and higher resting oxygen uptake than on placebo. Peak exercise oxygen uptake, blood glucose, blood pressure and heart rate were unchanged.

   ⚠What it shows: Very small randomised double-blind crossover trial in 12 recreationally active young men with modest VO2max; the condition-by-time interaction was non-significant and accuracy was already at ceiling, so the finding is exploratory.RCT · PLoS One

   Full breakdown →Cordyceps guide →VO2max Calculator →Acute Cordyceps militaris supplementation and elevated resting oxygen uptake with faster reaction times: A randomized crossover trial. PLoS One 2026
6. Supplementswell supported · human dataAdded 26 July 2026

   Caffeine trimmed cycling time trials, short and long

   Across 23 double-blind trials in trained cyclists, pre-exercise caffeine cut time-trial completion time with a small effect and zero heterogeneity, in both short efforts of 10 minutes or less and long ones of 20 minutes or more. Mean power output rose significantly only in the short trials.

   ⚠What it shows: Meta-analysis of 23 randomised, double-blind, placebo-controlled trials in healthy cyclists; effects are small (SMD −0.32 for completion time) and the subgroup difference between short and long trials was not statistically significant.Systematic review · Front Physiol

   Full breakdown →Caffeine guide →Caffeine Half-Life Calculator →Acute caffeine supplementation and cycling time-trial performance across different task durations: a systematic review and meta-analysis. Front Physiol 2026
7. Supplementspreliminary · human dataAdded 26 July 2026

   High-dose HMB lifted aerobic markers but not strength

   Trained men taking 90 mg per kg of fat-free mass per day of liquid HMB alongside high-intensity functional training improved a broad set of aerobic markers more than placebo, including VO2max and thresholds. Maximal isometric strength did not change with supplementation in either trained or untrained men.

   ⚠What it shows: One triple-blind randomised placebo-controlled trial in 53 trained and 37 untrained males over two 3-week periods with only 2 training sessions per week; no women, short duration, and the dose is far above the commonly studied 3 g/day.RCT · J Int Soc Sports Nutr

   Full breakdown →Lactate threshold explained →VO2max Calculator →HMB supplementation combined with high-intensity functional exercise supports aerobic capacity but not strength in trained and untrained males: a randomized controlled trial. J Int Soc Sports Nutr 2026
8. Supplementspreliminary · human dataAdded 26 July 2026

   Astaxanthin nudged muscle-damage markers in athletes

   In young male taekwondo athletes, 28 days of 12 mg daily astaxanthin produced a significant group-by-time interaction for creatine kinase, a marker of muscle damage, and higher antioxidant enzyme activity. Most burnout measures were unchanged.

   ⚠What it shows: One 28-day randomised, double-masked, placebo-controlled trial in young male taekwondo athletes; sample size not reported in the abstract. Several of the between-group differences were exploratory, and no burnout subscale showed a significant group-by-time interaction.Study · Nutr J

   Full breakdown →DOMS explained →Recovery Readiness Index →Effects of 28-day astaxanthin supplementation on psychological fatigue and biochemical markers in taekwondo athletes: a randomized controlled trial. Nutr J 2026
9. Supplementspreliminary · human dataAdded 23 July 2026

   Creatine before the session? Early signs say maybe.

   A small pilot trial suggests that taking creatine just before a resistance-training session may support slightly greater same-day strength than taking it during or after, though this is early, exploratory evidence rather than a firm recommendation.

   ⚠What it shows: A pilot crossover trial in just 11 active men, measuring single-session strength; the authors call it exploratory and say it needs confirming in larger, placebo-controlled studies.Pilot RCT (crossover) · n=11 · physically active men · Nutrients

   Full breakdown →Creatine monohydrate guide →Creatine Calculator →Acute Creatine Ingestion Before Resistance Training Enhances Strength Performance More than Ingestion During or After Training: A Randomized Crossover Pilot Trial. Nutrients 2026

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