Running Speed: How diet, lifestyle, and supplements may provide benefits.

Examine Database: Running Speed

Intervention	Grade	Evidence	Effect
Vitamin D	C	Participants: 33	Small Improvement
Caffeine	D	Participants: 254	No effect
L-Carnitine	C	Participants: 26	Small Improvement

Vitamin D

Participants: 33

Small Improvement

Caffeine

Participants: 254

No effect

L-Carnitine

Participants: 26

Small Improvement

Vitamin D

Small Improvement

Caffeine

No effect

L-Carnitine

Small Improvement

Research FeedRead all studies

The power of belief: does perceived caffeine ingestion improve running performance?

In this crossover trial in recreational runners, taking a placebo that the participants were told was caffeine improved running performance compared with taking nothing.

Does black currant extract improve running performance?

Examine Database References

Vitamin D - Małgorzata Magdalena Michalczyk, Artur Gołaś, Adam Maszczyk, Piotr Kaczka, Adam ZającInfluence of Sunlight and Oral D 3 Supplementation on Serum 25(OH)D Concentration and Exercise Performance in Elite Soccer PlayersNutrients.(2020 May 4)
L-Carnitine - Gamze E Orer, Nevin A GuzelThe effects of acute L-carnitine supplementation on endurance performance of athletesJ Strength Cond Res.(2014 Feb)
Caffeine - Wang Z, Qiu B, Gao J, Del Coso JEffects of Caffeine Intake on Endurance Running Performance and Time to Exhaustion: A Systematic Review and Meta-Analysis.Nutrients.(2022-Dec-28)