What can increase a diver's air consumption during a dive?

Strong currents and stress significantly increase a diver's air consumption because they create a physiological response that leads to higher work rates. When divers encounter strong currents, they must exert more effort to maintain their position or move through the water, requiring more frequent and deeper breaths. This physiological strain elevates heart rates and increases metabolic demands, leading to an increase in the volume of air consumed.

Additionally, stress can manifest from environmental factors or personal anxiety, resulting in quickened breathing patterns and inefficient gas exchange. Under stressful conditions, divers may breathe more rapidly and shallowly, further contributing to increased air consumption.

The other factors listed do influence air consumption but not to the same extent. Relaxation and slow movements, for example, lead to more efficient breathing and lower air consumption, while cold water can increase heart rate and may lead to more air use but not primarily as strong as the conditions created by currents and stress. A less buoyant wetsuit may affect buoyancy control but typically does not correlate directly to an increase in air consumption.