Now that I have been weight training for over 25 years, I have an intuitive sense of proper breathing mechanics when I lift weights, as many seasoned gym beasts can also attest to. However, those of you who are not as experienced or comfortable around a weight room might not know how to breathe properly.
The basic concept is that you will EXHALE on the exertion phase and INHALE on the relaxation phase of the exercise.
Let’s use the wide grip lat pulldown exercise as an example (which incidentally should be performed so that you bring the bar to your upper chest and NOT behind your back). You will exhale as you pull the bar down, then inhale when you return the bar to the starting position.
Most exercises can be performed using this basic technique, but if you are lifting very heavy weights, or even lifting heavy boxes, you can employ a breathing technique called the Valsalva Maneuver, in which you inhale deeply, then hold your breath while lifting the weight. This increases intra-abdominal pressure and thug confers support to the back. However, if you have high blood pressure, this movement can cause your blood pressure to skyrocket. Other relatively common symptoms which can occur during the Valsalva Maneuver are dizziness and fainting. As an alternative, you can simply contract your abdominals, keeping them tight, and continue to breathe normally during the movement.