2007, Piran, Slovenia

Environmental Ergonomics XII
Igor B. Mekjavic, Stelios N. Kounalakis & Nigel A.S. Taylor (Eds.), © BIOMED, Ljubljana 2007
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Figure 4. The regulation of A) mean skin heat flux (HFmean) and B) skin
blood flow on the back (skBFback) during 120-minute steady-load cycling.
The responses were compared at times indicated by the dotted lines.
DISCUSSION
Our results show that the increase in relative work rate induced by non-thermal factors
associated with muscle fatigue affect neither the level of increase in body temperature nor the
regulation of heat loss responses during prolonged steady-load exercise. These findings
suggests that the potentiation of sweating and peripheral skin vasomotor tone observed during
exercise with graded ischaemia (Eiken and Mekjavic, 2004; Kacin et al., 2004) and hypoxia
(Kacin et al., 2005) cannot be attributed to the increase in perceived whole-body exertion or
% V & O2peak per se, but to a specific physiological factor associated with reduced oxygen
delivery to the working muscle. Muscle metaboreflex most likely plays an important role in
this regard.
REFERENCES
Eiken, O. & Mekjavic, I. B. (2004). Ischaemia in working muscles potentiates the exerciseinduced
sweating response in man. Acta Physiol Scand. 181, 305-311.
Kacin, A., Golja, P., Eiken, O., Tipton, M. J., Gorjanc, J., & Mekjavic, I. B. (2005). Human
temperature regulation during cycling with moderate leg ischaemia. Eur.J Appl Physiol
95, 213-220.
Kacin, A., Golja, P., Eiken, O., Tipton, M. J., & Mekjavic, I. B. (2007). The influence of
acute and 23 days of intermittent hypoxic exposures on the exercise-induced forehead
sweating response. Eur.J Appl Physiol 99, 557-566.
Mekjavic, I. B. & Eiken, O. (2006). Contribution of thermal and nonthermal factors to the
regulation of body temperature in humans. Journal of Applied Physiology 100, 2065-
2072.