Blood oxygen levels refer to the amount of oxygen circulating in the blood. Normal blood oxygen levels fall between 75 and 100 millimeters of mercury (mm Hg) on arterial blood gas (ABG) test results.

Scientists rethink why giant insects once ruled the skies, finding oxygen may not explain their size or disappearance.

Scientific consensus is that high oxygen levels allowed these humongous fliers to exist, but a new study throws that idea ...

Taking a flight may be routine for some, but not much attention is paid to the physiological changes that take a toll on your ...

From childhood contests to grown-up moments of poolside bravado, most of us have tested our limits to see how long we can go without breathing. The aftermath includes experiencing a little ...

Fig.1: Tempo and mode in the body size evolution of Cambrian-Ordovician trilobites. Changes in maximum size (red) and mean size (blue) for each time slice, with lines and shading representing the mean ...

Low haemoglobin reduces oxygen delivery, making flying riskier due to lower cabin oxygen levels and increased fatigue or ...