Participants who meet the inclusion and exclusion criteria will undergo postural control assessment with the Biodex Balance System® and hand-eye coordination test with the Alternate Hand Wall Toss Test. Subjects will be given 65 ml of Turkish coffee (one cup) to ensure oral caffeine intake. The same assessments will be repeated 30 minutes after caffeine intake.

One cup of Turkish coffee contains 60 mg/65 ml (1 Turkish coffee cup) of caffeine. Participants will be instructed to sit for 10 minutes before drinking coffee. To prepare the Turkish coffee, 5 g of ground dry coffee will be mixed in 100 mL of tap water and left to boil in a coffee machine. When the first boil starts, it will be removed from the machine and poured into the cup. Then, 65 ml of Turkish coffee will be given to the subjects to ensure oral caffeine intake.

Postural control evaluation will be performed with "Biodex Balance System" (Shirley, NY). Three tests will be performed with the device: postural stability test, stability limits test, and the Modified Clinical Test for Sensory Interaction and Balance (mCTSIB). The test will then continue for 30 seconds, during which time the number of balls caught will be noted

Alternate hand wall toss test will be used to measure hand-eye coordination. The Alternate-Hand Wall-Toss Test is a test of hand-eye coordination, where the participant throw a ball against a wall from one hand in an underarm action, and attempt to catch it with the opposite hand. The test will then continue for 30 seconds, during which time the number of balls caught will be noted.