Performance language becomes confusing when every improvement is described as speed. A runner may sustain a fixed effort for longer without gaining the same percentage over a fixed distance. Caffeine research shows why the test format belongs in the story.

The evidence in context

A meta-analysis of 21 randomised trials involving 254 participants, mostly men, examined caffeine and endurance running. Benefits were larger in time-to-exhaustion tests than in time trials, where the average improvement was smaller. [1]

Running until exhaustion in a controlled test is not the same as finishing a race faster. The type of performance test changes how the numerical result should be interpreted.

Compare like with like

When you read a product claim, identify the exercise task and the result being reported. Ask whether it reflects your event or a different laboratory challenge. This makes the evidence useful without expecting a supplement to deliver a race improvement the study never measured.

Putting it into perspective

Before sharing a performance statistic, finish the sentence: improved by this amount on which test? That small addition makes the claim much clearer. It also helps you compare products or studies without treating results from different tasks as if they used a common scale.