Finding the peak of dynamic oxygen uptake during fatiguing exercise in fish [METHODS [amp ] TECHNIQUES]

Yangfan Zhang, Matthew J. H. Gilbert, and Anthony P. Farrell As fish approach fatigue at high water velocities in a critical swimming speed (Ucrit) test, their swimming mode and oxygen cascade typically move to an unsteady state because they adopt an unsteady, burst-and-glide swimming mode despite a constant, imposed workload. However, conventional MO2 sampling intervals (5-20 min) tend to smooth any dynamic fluctuations in active MO2 (MO2active) and thus likely underestimate the peak MO2active. Here, we used rainbow trout (Oncorhynchus mykiss) to explore the dynamic nature of MO2active near Ucrit by using various sampling windows and an iterative algorithm. Compared with a conventional interval regression analysis of MO2active over a 10-min period, our new analytical approach generated a 23% higher peak MO2active. Therefore, we suggest that accounting for such dynamics in MO2active with this new analytical approach may lead to more accurate estimates of maximum MO2 in fishes.
Source: Journal of Experimental Biology - Category: Biology Authors: Tags: METHODS [amp ] TECHNIQUES Source Type: research