This study investigated the effect of caffeine on physical performance in healthy citizens aged 70 years. The randomized, double-blind, placebo-controlled cross-over study was conducted in 15 males and 15 females recruited by their general practitioner. Participants abstained from caffeine for 48 hours and were randomized to receive one capsule of placebo then caffeine (6 mg/kg) or caffeine then placebo with one week in between. One hour after intervention we measured reaction and movement times, postural stability, walking speed, cycling at 65% of expected maximal heart rate, perceived effort (RPE) during cycling, maximal isometric arm flexion strength and endurance. Analysis was by intention-to-treat and p<0.05 was regarded as significant. Caffeine increased cycling endurance by 25% (95% CI: 13-38; p=0.0001), and isometric arm flexion endurance by 54% (95% CI: 29-83; p=0.0001). Caffeine also reduced the RPE after 5 minutes of cycling by 11% (95% CI: 5-17; p=0.002), and postural stability with eyes open by 25% (95% CI: 2-53; p=0.03). Caffeine ingestion did not affect muscle strength, walking speed, reaction and movement times. At the end of the study 46% of participants correctly identified when they received caffeine and placebo. Caffeine increased exercise endurance in healthy citizens aged 70 years, but the participants reasons for stopping the test may have varied between subjects as the cycling test was done at approximately 55% of maximal oxygen consumption. Further studies are required to investigate whether caffeine can be utilized to improve the physical performance of elderly citizens.