Measures have been called for to prevent accidents caused by arousal leve loss. By focusing on stamina, (closely related to arousal levels during work,) it has been clarified that arousal levels in the late night/early morning time zones of those with high physical fitness are maintained satisfactorily.
To check whether the arousal retention levels of those with relatively less physical fitness can be improved by enhancing stamina, arousal levels before and after enhancing physical fitness were compared. The comparison demonstrated that decreased arousal levels in the late night/early morning time zones could be suppressed by improving physical fitness with periodic physical training (such as jogging) over a six-month period (Fig. 1).
The relationship between physical fitness data and fatigue/health data of about 600 train drivers was analyzed to set a target level for men with less physical fitness. Based on this analysis, the average level of physical fitness of healthy train drivers was proposed as the target for strength improvement. This target represents the average physical fitness level of a 40 year-old Japanese male and is also a desirable standard for maintaining health, being easily achievable by regular light physical training.
A simple physical fitness measuring system was simultaneously developed using a wristwatch-type cardiotachometer (Fig. 2). This enables low-cost control and self-management of physical fitness.