Vital capacity of trained athletes is .............than that of non-athletes while of non-smokers is .............. than that of smokers.

Explanation

**Step-by-Step Solution:**

1. **Understanding Vital Capacity**: Vital capacity is defined as the maximum amount of air a person can exhale after a maximum inhalation. It is a measure of the lung's capacity to hold air and is influenced by physical fitness and health status.

2. **Comparing Athletes and Non-Athletes**: Trained athletes typically have a higher vital capacity than non-athletes. This is because athletes engage in regular physical training, which enhances their lung capacity and efficiency in oxygen exchange. Therefore, we can fill the first blank with "higher".

3. **Comparing Non-Smokers and Smokers**: Non-smokers generally have a higher vital capacity than smokers. Smoking introduces harmful substances into the lungs, damaging the alveoli and reducing the lung's ability to exchange gases effectively. Thus, we can fill the second blank with "higher".

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