Answer:
Our bodies deliberately send more blood to an erectile tissue between the two nostrils to increase its size and direct the air flowing through one of the nostrils. After a few hours, the airflow switches to the other nostril.
Explanation:
I’ll bet most people don’t realize that when you breathe through your nose, you do so more from one nostril than the other and your body knows to switch to the other nostril every few hours. I had no idea. I’m only aware of any difference in my nostrils when I’m congested!
This nasal cycle is controlled by the autonomic nervous system which also controls things we don’t think about like heart rate and breathing
Why do we do this? Some scientists believe the alternating airflow allows each nostril to maintain optimal moisture levels so no one side gets dried out. It may also protect against respiratory infections or allergies.
Others believe it’s tied to our olfaction or sense of smell. It’s possible that the quicker and slower airflow in each nostril optimizes us to the vast range of smells. Some smells take longer to detect and transmit to the brain.
Their brains are not working right. They don't think logically and they do stupid things. They can get brain damage, they can hut themselves and/or others.
Answer:
When skeletal muscles are trained by adding physical stress to them, this is called progressive resistance training (PRT).
Explanation:
During PRT, muscles are exercised against an <em>overload or resistance</em>; the overload is gradually increased in order to allow muscles to adapt. This allows for progressive strength increases over time.
Muscle fatigue is defined as a reduction in the ability to produce force due to exercise. This comprises:
- peripheral fatigue- due to changes at the junction between motor neurons and the muscle.
- central fatigue- caused by a reduced capacity to use voluntary force in relation to the capacity to use involuntary force
- and muscle damage- this is associated with several issues at the cellular level such as disrupted membranes and cytoskeletons; and tissue damage via torn muscle fibers, and collagen.
Overall, these may affect muscle fiber activation and the amount of force they are capable of producing- i.e. sustained strength. However, muscle fatigue can be greatly reduced via the maintenance of PRT. Also, apart from strength gains, PRT is <em>used for weight loss and muscle building</em>; common tools used in PRT include <em>free weights, elastic bands and exercise machines. </em>
