2007, Piran, Slovenia

Environmental Ergonomics XII
Igor B. Mekjavic, Stelios N. Kounalakis & Nigel A.S. Taylor (Eds.), © BIOMED, Ljubljana 2007
The IHE group had a decreased muscle deoxy-Hb (P = 0.02) (Figure 3A) and
increased t-Hb (P = 0.01) (Figure 3B) during the final stages of heavy exercise
following the intervention compared with baseline, whereas muscle oxy-Hb and TOI
was unchanged. No changes were evident in muscle oxygenation in the placebo group
at any point during incremental exercise.
DISCUSSION
The main novel findings of this preliminary study are: IHE can offset some degree of
EIH; however, potentially due to a greater degree of hypocapnia, cerebral oxygenation
was reduced. Despite this potential compromise in cerebral oxygenation, exposure to
IHE may induce some physiological adaptations at the muscle tissue level. We
speculate that the unchanged V & O2peak following IHE, consistent with many studies,
might reflect a balance between these central (cerebral) and peripheral (muscle)
adaptations.
ACKNOWLEDGEMENTS
We thank the volunteers involved in this study. The financial support from the
Lincoln University Research Fund is acknowledged, as is the summer scholarship
provided by the Department of Physiology, University of Otago to Nik Beattie.
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