A 2026 review of 20 studies found caffeine can help footballers repeat hard runs and sprints, but the gain is not free: effort may feel similar while lactate and blood sugar rise.

The study titled “Does acute caffeine ingestion improve high-intensity interval exercise performance?” brought together 20 studies with 320 adults. Each person used caffeine on one day and a placebo on another. The tests covered several sports. Football matches ask players to sprint, press, recover, and go again, so the broader exercise evidence is relevant.

The paper’s main performance effect was small: Hedges’ g = 0.28, with a 95% confidence interval from 0.14 to 0.43. In plain terms, caffeine nudged high-intensity interval performance up. The benefit also showed up in trained athletes and in study groups given around 3 mg/kg. Effort ratings stayed about the same, while lactate and blood sugar rose. Those changes show the body was still working hard and using fuel. The player may have done more work without reporting more effort.

For football staff, a normal effort rating after caffeine is not enough. If GPS shows more sprints or more high-speed running, count that as extra work when planning recovery.

Football trials show the same pattern

The closest football studies used match-style tests. Del Coso et al. found that 3 mg/kg caffeine in an energy drink improved jump height, a 7×30 m sprint test, high-intensity distance, and sprint count in male semiprofessional players. The game data make the point clearer: total distance rose from 7,352 m to 7,782 m, distance above 13 km/h rose from 1,205 m to 1,436 m, and sprint bouts rose from 24 to 30. Lara et al. found higher jump height, peak sprint speed, total distance, sprint bouts, and distance above 18 km/h in a similar study with female players.

Both studies used energy drinks. They are useful for a common match-day product, though less clean as caffeine-only tests.

Apostolidis et al. used 6 mg/kg caffeine before a stop-start treadmill test. The footballers lasted longer: 719 seconds with caffeine versus 469 seconds with placebo. Jump height improved, lactate and blood sugar were higher, and effort rating was slightly lower. Again, caffeine raised output without removing the body cost.

Football evidence is still mixed

Ferreira et al. reviewed 16 football trials and found no clear average benefit for repeated sprints, jumping, aerobic endurance, agility reaction time, or effort rating. The evidence quality was very low to low. Lopes-Silva et al. focused on repeated sprint ability and found no caffeine benefit for total work, best sprint, or last sprint.

A repeated-sprint drill asks for short bursts again and again. A simulated match adds pacing, jumping, and longer running. A run to exhaustion tests how long a player can keep going. Caffeine may help one of those more than another, and the 2026 review found that rest time changed the effect. The cautious claim is stronger than the broad one: caffeine may help footballers produce more high-intensity work in some settings, while repeated-sprint tests alone remain less convincing.

What staff should monitor

Do not treat these studies as a dose recommendation. The ISSN position stand and AIS guidance both treat caffeine as individual: response and side effects vary, and athletes should trial it before important competition. A side-effect review also found higher doses brought more side effects.

For football staff, the practical takeaway is to record the load. If caffeine is already part of a player’s approved routine, compare GPS output, sprint count, heart-rate response, effort rating, sleep, and next-day recovery against normal training.