Answer: Intensity is more important when it comes to improving physical fitness. Maintaining it at a certain level would keep the physical prowess at a standstill, which is also not a bad thing depending on what a person wants. If one however wishes to increase his abilities then increasing intensity is necessary. Of course, it should happen gradually, not all at once, since that could result in serious injury.
First line: <span>mechanical, chemical and microbial Second line: internal/non-specific, involves the immune system Third line: internal/specific</span>
