Randomised trial · Journal of sports sciences · 2015Abstract only

Sodium phosphate and caffeine for repeated sprinting

What it found

In 12 female team-sport players, sodium phosphate and caffeine together made repeated sprints faster than a placebo.

Sodium phosphate on its own also made sprints faster than a placebo.

What they found

Studies in people

Combined loading and sprints

Total sprint times were faster after sodium phosphate and caffeine together than after a placebo, in Set 1, Set 2, Set 3 and overall. They were also faster than caffeine alone in Set 3 and overall, and faster than sodium phosphate alone in Set 3.

Sodium phosphate alone

Total sprint times were faster after sodium phosphate alone than after a placebo in Set 1 and Set 3.

Best sprint times

Best sprint results were faster after sodium phosphate and caffeine together than after a placebo and after caffeine alone, both in Set 3. Best sprint times were also faster after sodium phosphate alone than after a placebo across all sets.

What the authors conclude

“Sodium phosphate and combined sodium phosphate and caffeine loading improved repeated-sprint ability.”
Buck C, Guelfi K, Dawson B, McNaughton L, Wallman K, 2015

Also in their conclusions

  • They conclude that sodium phosphate and combined sodium phosphate and caffeine loading improved repeated-sprint ability.

How it was done

Twelve female team-sport players took part in four trials: sodium phosphate with caffeine, sodium phosphate with a caffeine placebo, caffeine with a sodium phosphate placebo, and a placebo for both. Each trial was about 21 days apart, and after each one they did a simulated team-game circuit of 4 x 15 minute quarters with 6 x 20 metre repeated sprints before, at half-time and after the end.

What it can’t tell you

  • We summarised it from the abstract only.
  • This was a small trial of 12 female team-sport players, so the results may not apply to other people or other sports.
  • The trials were about 21 days apart, so the findings only cover this short-term loading and testing schedule.

The paper

Title
Effects of sodium phosphate and caffeine loading on repeated-sprint ability
Type
Randomised controlled trial
Evidence
Studies in people
Summarised from
Abstract only
Cite
Buck C, Guelfi K, Dawson B, McNaughton L, Wallman K (2015). Effects of sodium phosphate and caffeine loading on repeated-sprint ability. Journal of sports sciences. doi:10.1080/02640414.2015.1025235PubMed 25827059DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error