An investigation was carried out to study the homeostatic thermoregulatory responses of a volunteer during exercise. The volunteer performed a standardized workout on a cycle ergometer at various ambient air temperatures under two different physiological conditions: when clinically dehydrated and when fully hydrated.
The table shows the relative skin blood flow (perfusion rate) measured during the trials:
| Ambient air temperature in ∘C^\circ\text{C}∘C | Relative skin blood flow in arbitrary units when dehydrated | Relative skin blood flow in arbitrary units when fully hydrated |
|---|---|---|
| 16.0 | 5 | 8 |
| 20.0 | 7 | 14 |
| 24.0 | 8 | 22 |
| 28.0 | 11 | 35 |
| 32.0 | 16 | 54 |
| 36.0 | 25 | 80 |
Suggest why the investigation was carried out using the same volunteer for both trials.
Compare the effect of increasing ambient air temperature on relative skin blood flow when dehydrated and when fully hydrated.
Suggest why relative skin blood flow increases during exercise and why it is lower when the volunteer is dehydrated compared to when they are fully hydrated.
Suggest a method that could be used to monitor either the skin blood flow or the skin temperature of a volunteer during exercise.
