Endpoint
Mean power output
CAT:outcome/mean-power-outputreported in W5 findings from 3 compounds
What moved it
How to read these marks5 findings · 3 compounds · 2 null · by evidence strength
| Compound | Direction | Findings | Strongest evidence |
|---|---|---|---|
| nitrate | no effect | 1 | Evidence strength: moderate. Human evidence with one recorded weakness, or capped at moderate by its design or by unread numbers. |
| caffeine | up 2 · no effect 1 | 3 | Evidence strength: very limited. Human evidence with major recorded weaknesses, or non-human, uncontrolled or unverified evidence. |
| magnesium(2+) | down | 1 | Evidence strength: very limited. Human evidence with major recorded weaknesses, or non-human, uncontrolled or unverified evidence. |
Reported to move it
3 findings
magnesium(2+) — decreases
Very limitedEvidence strength: very limited. Human evidence with major recorded weaknesses, or non-human, uncontrolled or unverified evidence.Finding“Compared with the placebo, the mean power output was lower ( p = 0.03) after magnesium supplementation in 11/13 participants (mean decrease of 24 ± 36 W).”
Quoted verbatim from Short-Term Magnesium Supplementation Has Modest Detrimental Effects on Cycle Ergometer Exercise Performance and Skeletal Muscle Mitochondria and Negligible Effects on the Gut Microbiota: A Randomized Crossover Clinical Trial.. - Study
- crossover
- Participants
- 13
- Duration
- 9 days
- Dose
- magnesium chloride 300 mg (ReMag) twice per day for 9 days
- Population
- Healthy regularly exercising adults aged 18-40; primary outcome (sprint exercise performance); 30-second all-out cycle ergometer sprint, complete data available for 13 of 15 participants
Short-Term Magnesium Supplementation Has Modest Detrimental Effects on Cycle Ergometer Exercise Performance and Skeletal Muscle Mitochondria and Negligible Effects on the Gut Microbiota: A Randomized Crossover Clinical Trial.2025PMID:40077784Industry fundedPermalink
caffeine — increases
Very limitedEvidence strength: very limited. Human evidence with major recorded weaknesses, or non-human, uncontrolled or unverified evidence.Findingreplicated ×1“The mean power output during the all-out effort was increased following caffeine ingestion compared with placebo (794+/-164 vs 750+/-163 W; P=0.05).”
Quoted verbatim from Caffeine lowers perceptual response and increases power output during high-intensity cycling.. - Study
- crossover
- Participants
- 11
- Dose
- 5 mg/kg caffeine capsule
- Population
- male cyclists
Caffeine lowers perceptual response and increases power output during high-intensity cycling.2004PMID:15370494Permalink
caffeine — increases
Very limitedEvidence strength: very limited. Human evidence with major recorded weaknesses, or non-human, uncontrolled or unverified evidence.Findingreplicated ×1“Mean power (153 ± 48 vs 146 ± 43 W) was significantly higher in CAF-5 vs PL, respectively.”
Quoted verbatim from Effects of different doses of caffeine on anaerobic exercise in boys.. - Study
- crossover
- Participants
- 26
- Dose
- 5 mg/kg anhydrous caffeine (CAF-5) in cherry-flavored Sprite, 60 min before testing
- Population
- 8- to 10-year-old boys; CAF-5 dose (5 mg/kg) vs placebo during a 30-s Wingate test
Effects of different doses of caffeine on anaerobic exercise in boys.2015PMID:25051124Permalink
Measured, no effect detected
2 findings
nitrate — no detected effect on
ModerateEvidence strength: moderate. Human evidence with one recorded weakness, or capped at moderate by its design or by unread numbers.FindingNull result“A random effects model was performed on six studies and showed that dietary nitrate had significant effects on time-to-peak power (SMD: -0.66, 95% CI: -1.127 to -0.192, p = 0.006) but not on mean power, peak power, or minimum power.”
Quoted verbatim from Effects of Dietary Nitrate Supplementation on High-Intensity Cycling Sprint Performance in Recreationally Active Adults: A Systematic Review and Meta-Analysis.. - Study
- meta-analysis
- Population
- healthy recreationally active adults performing 30-s cycling sprints
Effects of Dietary Nitrate Supplementation on High-Intensity Cycling Sprint Performance in Recreationally Active Adults: A Systematic Review and Meta-Analysis.2024PMID:39203900Permalink
caffeine — no detected effect on
Very limitedEvidence strength: very limited. Human evidence with major recorded weaknesses, or non-human, uncontrolled or unverified evidence.FindingNull result“In comparison with placebo, caffeine had no significant effect on peak power (p = 0.11), mean power (p = 0.55), or time to peak power (p = 0.17).”
Quoted verbatim from Caffeine and sprinting performance: dose responses and efficacy.. - Study
- crossover
- Dose
- 2, 4, 6, 8, or 10 mg/kg body mass caffeine, single dose 1 hour before sprint trials
- Population
- 17 well-trained men, sprint cyclists
Caffeine and sprinting performance: dose responses and efficacy.2012PMID:22388491Permalink
How it is measured
Average mechanical power sustained across a fixed-duration maximal effort, cycle ergometer, duration recorded with each finding.
Measured, not recorded
- Subject
- mean power output
- Measurements
- 1 measurement
- Recorded as a finding
- No
Show what was measured
mean power output
no effect, p = 0.994
BRJ supplementation prevented AM losses of mean power output (p = 0.994), anaerobic capacity (p = 0.941), and total work (p = 0.933) in the AM-BRJ compared to the PM condition
PMID:33430250 · one of two readings recorded this
Sources cited
5 papers
- Subject
- mean power output
- Findings
- 5
- Papers
- 5
Short-Term Magnesium Supplementation Has Modest Detrimental Effects on Cycle Ergometer Exercise Performance and Skeletal Muscle Mitochondria and Negligible Effects on the Gut Microbiota: A Randomized Crossover Clinical Trial.record2025PMID:400777841 finding
Effects of Dietary Nitrate Supplementation on High-Intensity Cycling Sprint Performance in Recreationally Active Adults: A Systematic Review and Meta-Analysis.record2024PMID:392039001 finding
Effects of different doses of caffeine on anaerobic exercise in boys.record2015PMID:250511241 finding
Caffeine and sprinting performance: dose responses and efficacy.record2012PMID:223884911 finding
Caffeine lowers perceptual response and increases power output during high-intensity cycling.record2004PMID:153704941 finding