Sodium phosphate and caffeine for repeated sprints in male athletes
What it found
Sodium phosphate led to the fastest sprint times compared with placebo, though the differences were not statistically significant.
The study was in eleven male team-sport athletes.
What they found
Studies in people
Sprint times overall
There were no interaction effects between trials for first-sprint, best-sprint or total-sprint times. However, sodium phosphate gave the fastest times for all sprints compared with placebo, with moderate to large effect sizes and likely to very likely chances of benefit.
Sodium phosphate vs caffeine
Compared with caffeine, sodium phosphate gave possible to likely chances of benefit for first-sprint, best-sprint and total-sprint times across numerous sets. It also gave a possible chance of benefit compared with the combined sodium phosphate and caffeine for best-sprint in set 2.
Combined vs placebo
Compared with placebo, the combination of sodium phosphate and caffeine gave moderate effect sizes and possible to likely benefit for numerous sprints.
Caffeine vs placebo
Compared with placebo, caffeine alone gave a moderate effect size for first-sprint in set 3 and likely chances of benefit for a number of sets.
What the authors conclude
“While not significant, ES and qualitative analysis results suggest that SP supplementation may improve repeated-sprint performance when compared with placebo.”
Also in their conclusions
- They conclude that while not significant, effect sizes and qualitative analysis suggest that sodium phosphate supplementation may improve repeated-sprint performance when compared with placebo.
How it was done
Eleven male team-sport players took part in four trials: sodium phosphate plus caffeine, sodium phosphate plus placebo, caffeine plus placebo, and placebo alone. They loaded with sodium phosphate for six days and took caffeine one hour before a simulated team-game circuit with repeated sprints.
What it can’t tell you
- We summarised it from the abstract only.
- The study was small, with only eleven male team-sport athletes, so the results may not apply to other people or sports.
- The differences in sprint times were not statistically significant, so the benefit of sodium phosphate is uncertain.
Who paid
- Authors work at
- The University of Western Australia, Australia
The paper
- Title
- Effects of sodium phosphate and caffeine ingestion on repeated-sprint ability in male athletes
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Abstract only
- Cite
- Kopec BJ, Dawson BT, Buck C, Wallman KE (2016). Effects of sodium phosphate and caffeine ingestion on repeated-sprint ability in male athletes. Journal of science and medicine in sport. doi:10.1016/j.jsams.2015.04.001PubMed 25953613DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error