Assessment of exercise-induced stress via automated measurement of salivary cortisol concentrations and the testosterone-to-cortisol ratio: a preliminary study.

In this study, our aim was to validate whether the automated measurement of salivary testosterone and cortisol concentrations and the testosterone-to-cortisol (T/C) ratio, considering their individual circadian rhythms can be used to assess the stress response of male athletes to different exercise intensities accurately and effectively. We measured the salivary testosterone and cortisol concentrations and their respective serum concentrations that were collected from 20 male long-distance runners via passive drooling in the morning and evening for two consecutive days involving different exercise intensities. An electrochemiluminescence immunoassay was performed to evaluate the salivary testosterone and cortisol concentrations.

Differences in stress response between two altitudes assessed by salivary cortisol levels within circadian rhythms in long-distance runners.

There are conflicting reports regarding the efficacy of cortisol as a stress marker in altitude training due to the influence of the circadian rhythm. This study aimed to verify whether the automated measurement of salivary cortisol concentration via sequential sampling could detect the differences in exercise stress between two altitudes. We enrolled 12 elite female long-distance runners living near sea level.

Konjac Glucomannan Attenuated Triglyceride Metabolism during Rice Gruel Tolerance Test.

In a recent study, we showed that konjac glucomannan (KGM) inhibits rice gruel-induced postprandial increases in plasma glucose and insulin levels. To extend this research, we investigated the effects of KGM addition to rice gruel on pre- and postprandial concentrations of circulating lipoprotein lipase (LPL), glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1), hepatic triglyceride lipase (HTGL), free fatty acids (FFA), and triglycerides (TG). A total of 13 Japanese men, without diabetes, dyslipidemia, or gastrointestinal diseases, interchangeably ingested rice gruel containing no KGM (0%G), rice gruel supplemented with 0.

Significance of serum branched-chain amino acid to tyrosine ratio measurement in athletes with high skeletal muscle mass.

Background: Few nutritional markers reflect the hypermetabolic state of athletes with high levels of skeletal muscle. Although branched-chain amino acids (BCAA) play crucial roles in protein metabolism in skeletal muscle, the relationship between skeletal muscle mass and amino acid imbalances caused by the metabolism of BCAA and aromatic amino acids remains unclear. The aim of this study is to test the hypothesis that athletes with high levels of skeletal muscle mass have plasma amino acid imbalances, assessed by serum BCAA to tyrosine ratio (BTR) which can be measured conveniently.

Assessment of exercise-induced stress by automated measurement of salivary cortisol concentrations within the circadian rhythm in Japanese female long-distance runners.

Background: Overtraining syndrome, caused by prolonged excessive stress, results in reduced performance and cortisol responsiveness in athletes. It is necessary to collect saliva samples sequentially within circadian rhythm for assessing exercise stress by measuring cortisol concentrations, and automated cortisol measurements using electrochemiluminescence immunoassay (ECLIA) may be useful for measuring a large number of saliva samples. In this study, we evaluated the appropriate use of cortisol-based exercise stress assessment within the circadian rhythm, which may diagnose and prevent overtraining syndrome in athletes.

Glucomannan Inhibits Rice Gruel-Induced Increases in Plasma Glucose and Insulin Levels.

Objective: Given the association between diabetes suppression and inhibition of diet-induced elevation in glucose and insulin, we investigated the effects of adding glucomannan to rice gruel on pre- and postprandial glucose and insulin concentrations.

Methods: A total of 25 Japanese subjects without a history of diabetes or gastrointestinal disease (all males; aged 37-60 years; body mass index 20.4-31.

[Improvement in peripheral blood T cell subset imbalance in a house with an elimination system for various allergens].

We analyzed the change of peripheral blood T cell subsets after moving into a house with a Healthy Air system (HAS) elimination system for various allergens, e.g. pollens, house dusts, etc.

[Evaluation of mental stress tests among medical students based on salivary sample collected just before the national license examination].

We investigated salivary amylase (sAMY) and chromogranin A (sCgA) in students before the national license examination in order to investigate the relationship between stress biomarkers and the Profile of Mood States (POMS) psychological test. Fifty-one medical students that provided informed consent were tested for sAMY activity and sCgA concentration by means of the amylase monitor method (NIPRO) and an ELISA kit (Yanaihara), respectively. The POMS psychology test (shortened form) was purchased from Chiba Test Center, and all students fully answered the lifestyle questionnaires.