الإنتاج البحثي لأعضاء هيئة التدريس بالكلية V.8 - Flipbook - Page 167
and P tw were reduced (7 ± 3% and 31 ± 9%, respectively, p = 0.014), while VATMS was not affected
by the rowing effort in normoxia. With hyperoxia, the deficit in MVC and P tw was attenuated,
while VATMS was unchanged.
Conclusion: These data indicate that even though hyperoxia restores frontal lobe oxygenation the
resultant attenuation of arm muscle fatigue following maximal rowing is peripherally rather than
centrally mediated.
(3) Nielsen, H.B., Volianitis, S., Secher, N.H. (2022). Dose of Bicarbonate to Maintain
Plasma pH During Maximal Ergometer Rowing and Consequence for Plasma Volume.
Frontiers in Physiology, 13, 828708
Rowing performance may be enhanced by attenuated metabolic acidosis following bicarbonate
(BIC) supplementation. This study evaluated the dose of BIC needed to eliminate the decrease in
plasma pH during maximal ergometer rowing and assessed the consequence for change in plasma
volume. Six oarsmen performed “2,000-m” maximal ergometer rowing trials with BIC (1 M; 100–
325 ml) and control (CON; the same volume of isotonic saline). During CON, pH decreased from
7.42 ± 0.01 to 7.17 ± 0.04 (mean and SD; p < 0.05), while during BIC, pH was maintained until
the sixth minute where it dropped to 7.32 ± 0.08 and was thus higher than during CON (p < 0.05).
The buffering effect of BIC on metabolic acidosis was dose dependent and 300–325 mmol required
to maintain plasma pH. Compared to CON, BIC increased plasma sodium by 4 mmol/L,
bicarbonate was maintained, and lactate increased to 25 ± 7 vs. 18 ± 3 mmol/L (p < 0.05). Plasma
volume was estimated to decrease by 24 ± 4% in CON, while with BIC the estimate was by only 7
± 6% (p < 0.05) and yet BIC had no significant effect on performance [median 6 min 27 s (range
6 min 09 s to 6 min 57 s) vs. 6 min 33 s (6 min 14 s to 6 min 55 s)]. Bicarbonate administration
attenuates acidosis during maximal rowing in a dose-dependent manner and the reduction in plasma
volume is attenuated with little consequence for performance.
(4) Volianitis, S., Koutedakis, Y., Secher, N.H. (2022). Editorial: Advances in Rowing
Physiology. Frontiers in Physiology, 13, 939229
Almost 100 years ago, it was considered that “the rowing of a crew in a racing shell with sliding
seats is a form of exercise in which a greater total energy expenditure is attainable, for periods of
five to 20 min, than under any other conditions. No other exertion comes so near to bringing the
entire muscle mass of the body into maximal extension and contraction” (Henderson and Haggard,
1925). Since then many studies confirmed this notion and showcased rowing as “the ultimate
challenge to the human body” (Volianitis and Secher, 2009). The articles in this Research Topic
address a range of questions relevant not only to Olympic rowing performance, but also to the
recently increasingly popular indoor rowing.
(5) Sejersen, C., Fischer, M., Mattos, J.D., Volianitis, S., Secher, N.H.(2021). Fluctuations in
cardiac stroke volume during rowing. Scandinavian Journal of Medicine and Science in
Sports, 31(4), pp. 790–798
Preload to the heart may be limited during rowing because both blood pressure and central venous
pressure increase when force is applied to the oar. Considering that only the recovery phase of the
rowing stroke allows for unhindered venous return, rowing may induce large fluctuations in stroke
volume (SV). Thus, the purpose of this study was to evaluate SV continuously during the rowing
stroke. Eight nationally competitive oarsmen (mean ± standard deviation: age 21 ± 2 years, height
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