What factors are most likely to affect the breathing rate?

Some of the factors that affect the breathing rate are:

1. While exercising or doing intense physical activity, the body requires more energy due to which the demand of oxygen increases. This increases the rate of breathing of the person.
2. While sleeping and resting, the breathing rate decreases as the body requires less energy.
3. Allergic reactions increase the rate of breathing as allergic reactions narrow the nasal passage leading to a demand for more oxygen.
4. Stress and anxiety increases the breathing rate as the stress hormones trigger the body's fight or flight response.