Mean changes ( SEs ) in the time required to complete the TMT A and B after consumption of the HF ( -8.6 0.4 and -16.5 0.8 s , respectively ) and IF ( -6.7 0.5 and -14.2 0.5 s , respectively ) drinks significantly ( P < 0.0001 ) differed from that after consumption of the LF drinks ( -0.8 1.6 and -1.1 0.7 s , respectively ) .