FIGURE 1.

The experimental design. The experiment was conducted in 2 days and consisted of two sessions: training (indoor cycling) and rest session. The training session was conducted on the first day, followed by the rest session on the other day. The participants conducted critical fusion frequency (CFF) measurement at three phases defined in relation to the exercise: before the start of the cycling exercise (run 1), immediately (i.e. including 3 min of dark adaptation) after the end of the cycling exercise (run 2), and 30 min after the end of the cycling exercise. In the rest session, the participants were seated in the same environmental conditions as during cycling and did not perform any physical activity. They conducted CFF measurement in the same way as in the training session at three phases defined in relation to the duration of the cycling exercise in the training session