Well, duh… you kinda need to do it keep oxygen flowing to the working muscles!
In my experience training PT clients and Taekwondo students is that this very obvious fact does get overlooked in the performing of the exercise or activity. This is especially the case when learning a new exercise or action because the body is unfamiliar with the technique so the mind has to think about too much and literally forgets to breathe. Fatigue quickly sets in and makes the exercise harder than it needs to be and can be discouraging for the doer.
A technique called Valsava Breathing will go a long way to create good rhythm, maintain core structure, and keep the oxygen flowing. What this means is that you INHALE on the Negative portion of the exercise (for example the downward phase of a pushup), HOLD on the positive (the actual press portion of the pushup), and EXHALE sharply at the peak of the technique (full extension of the arms in the pushup).
What this does is create constant core tension with the increased pressure in the abdominal and thoracic cavities, providing great structure to the exercise and more importantly protecting the spine during the movement.
By exhaling sharply at the end of each action you add even more tension (touch your abs when you sneeze or cough and you’ll know what I mean), and doing this sharply means you’ll quickly expel the carbon dioxide in your lungs and refill with that precious oxygen! Keep in mind that you want to maintain about 30% of lung capacity so don’t fully exhale, as you still want to have some air pressure to support you as you inhale smoothly on the negative movement.
Another example of correct breathing for Squats would be as follows
Some things to be aware of is that if you are lifting heavy weights it will increase your blood pressure, so if you are prone to this take frequent rests in between sets.
Try this technique next time you workout, and you will quickly see an improvement in endurance, technique and overall core strength.