Acute effects of low versus high caffeine dose consumption on postural balance in middle-aged women

Effects of Caffeine Ingestion on Human Standing Balance: A Systematic Review of Placebo-Controlled Trials

“…Following assessment of these eighteen full articles against the eligibility criteria, a further ten were excluded. Reference list screening resulted in one additional study, meaning a total of nine eligible studies were included in the systematic review [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ].…”

“…Of the nine eligible studies, five investigated the effects of caffeine on human standing balance in a participant group aged less than 65 years (i.e., younger) [ 25 , 26 , 27 , 28 , 32 ]. Five studies included a participant group with an average age of 65 years or over (i.e., older) [ 27 , 29 , 30 , 31 , 33 ].…”

“…Three of five studies including younger participant groups were of moderate quality [ 25 , 26 , 27 ] and the remaining two were of strong quality [ 28 , 32 ] (see Table 3 ). Franks et al (1975) was the only study that was not stated to be double-blind; although participants were described as “ignorant” to their treatment group, this study did not mention blinding of the experimenter [ 25 ].…”

“…Franks et al (1975) was the only study that was not stated to be double-blind; although participants were described as “ignorant” to their treatment group, this study did not mention blinding of the experimenter [ 25 ]. Of note, while four of the five studies stated that participants were randomly allocated to group/condition, Ben Waer et al (2020) did not report randomisation or counterbalancing [ 32 ]. Swift and Tiplady (1988) included the smallest sample size of all studies, with six participants in each age group, and also failed to report variance for some non-significant results [ 27 ].…”

“…The studies which reported the duration of caffeine abstinence prior to testing used a period of between 12 and 24 h [ 26 , 28 , 32 ], but Franks et al (1975) did not report the duration which participants abstained from caffeinated beverages [ 25 ] and Swift and Tiplady (1988) made no mention of pre-experiment caffeine abstinence [ 27 ]. Four of five studies used an absolute caffeine dose of between 100 and 500 mg [ 26 , 27 , 28 , 32 ], with the 4.3 mg∙kg −1 (i.e., relative) dose used by Franks et al (1975) also likely to fall within this range [ 25 ]. Three studies used caffeine in capsule form [ 27 , 28 , 32 ] and two studies added caffeine to decaffeinated coffee [ 25 , 26 ].…”