ABSTRACT
Although there are a number of reported cases of increased cerebral blood flow during exercise, there are no reports on the relation between changes of blood flow during exercise and attentional function. The purpose of this study is to clarify the relation between changes of blood flow during exercise with AT intensity and attentional function, using near-infrared spectral analysis. The subjects were 10 healthy males. The research protocol was to conduct steady load exercise. We randomly conducted two invention trials: 1) an exercise/task trial in which a trail making test (TMT) was performed as an attentional assignment during steady load exercise, and 2) a rest/task trial in which TMT was performed during rest as a control. As a result, we observed the following: increase of oxy-Hb in the prefrontal cortex during AT exercise, the significant shortening of TMT during exercise from 69.1±10.2 seconds to63.2±7.2seconds, and, with further control, that the more oxy-Hb rises, the more TMT time is shortened. From these results, it is suggested that 10 minutes of exercise would improve attentional function, and furthermore, there is a possibility that increased cerebral blood flow may be involved with the improvement of attentional function.
ABSTRACT
The aim of the present study was to examine whether amount of oral cortisol, immunoglobulin A (IgA), chromogranin A (CgA) and inflammatory cytokines, might be affected by prolonged strenuous exercise. Ten young male volunteers either exercised on recumbent ergometer at 75 % VO<sub>2</sub> max for 60 min (exercise session) or sat quietly (resting session). Saliva samples were obtained at 60 min intervals during sessions for measurements of salivary stress markers (cortisol, IgA and CgA), salivary inflammatory cytokines, such as interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) and osmolality. Saliva flow rate was decreased and saliva osmolality was increased during the 60-min exercise. Saliva cortisol and CgA concentrations and secretion rates were increased during and after the exercise, whereas saliva IgA concentration and secretion rates were decreased after the exercise. Salivary inflammatory cytokines was increased during and after the exercise. The present findings suggested a single bout of prolonged strenuous exercise caused a transient increase in the salivary cortisol, CgA and inflammatory cytokines levels, whereas salivary IgA concentration and secretion rates were decreased after the exercise. Further studies, however, are needed to delineate whether or not salivary stress markers and inflammatory cytokines may be used as biological markers to determine the host responses to acute prolonged strenuous exercise.