Download Effects of the induced evening thermal stress on nightly

Reasoning of dissertation topic and competency of potential supervisor for
admission onto joint LSU and TU doctoral studies in 2014
Area of research (title and code)
Field of research (title and code)
Topic of research
Institution
Biomedical sciences
Biology (01B)
Hyperthermia, hypothermia, and efficiency of
motor and cognitive systems
LSU
Potential supervisor
Pedagogical and
Name, surname
scientific degree
Assoc. Prof., dr.
Marius Brazaitis
Academic position
Senior researcher
Short reasoning of proposed dissertation topic
Title
Effects of the induced evening thermal stress for nightly – morning and morning
functional efficiency of neuromuscular and cognitive systems.
Summary (relevance, hypothesis, methodology, not more than 2000 symbols)
In the scientific literature thermal stress effect is described as a muscular relaxant and a central
nervous system inhibitory (Lee et al., 2012; Sutkowy et al., 2013). It has already been found that
taking ordinary sauna (3 times x 20 min with 10 min break; 80–90oC; 30% environment relative
humidity) internal body (rectal) temperature is increasing and reaching >39oC (Sohar et al., 1976).
This body temperature is described as a high physiological thermal stress (hyperthermia) (Moran et
al., 1998, 1999; Brazaitis et al., 2012), which worsens function of cognitive system (Racinais et al.,
2008) and reduces central activation of working muscles (Nybo and Nielsen, 2001; Racinais et al.,
2008; Brazaitis et al., 2012). Residual effect of thermal stress (all body hyperthermia) for
neuromuscular and cognitive systems functional efficiency is still not investigated. So it is not clear
how in the evening induced thermal stress (hyperthermia) by sauna session will effect morning and
nightly – morning mental work capacity, cognitive and neuromuscular systems functional
efficiency, and changes of stress hormones. Working hypothesis is in the evening induced
hyperthermia will worsen nightly mental work capacity and significantly reduce concentration of
stress hormones (cortisol and catecholamines) in the blood because of that the strength of electric
impulses from brain and spinal cord will be weaker, spread duration will be longer, moreover
resistance to fatigue will reduce, attentions and memory will be worse. Results of this research will
be useful for people whose operating activities are related with making decisions, focusing
attention, memory and manual labour.
Currently I am supervisor of _3_ doctoral students.
Marius Brazaitis
Supervisor
(signature)
Date
(Name, surname)