Table 1. NASA-TLX subjective workload values for the five subscales between the two conditions.

Data are presented as mean ± SD.

	NASA-TLX workload
	Mental demand	Physical demand	Temporal demand	Performance	Effort	Frustration
Stroop task	68 ± 14	13 ± 10	71 ± 17	25 ± 13	77 ± 9	46 ± 12
Control	34 ± 19	11 ± 6	35 ± 18	25 ± 13	33 ± 16	25 ± 14
P	< 0.001	0.560	< 0.001	1.000	< 0.001	< 0.001

Motivation for the time trial did not differ significantly between conditions (P = 0.443). Values were 3.3 ± 0.9 and 3.5 ± 0.8 for the Stroop task and the control condition respectively.