The Valsalva maneuver consists of a forced expiration with closed glottis. This operation can be used for different purposes, for example to decrease the heart rate in case of tachycardia or to calm an annoying hiccup.
The Valsalva maneuver greatly increases the intrathoracic and intra-abdominal pressure, favoring inter alia the emptying of the viscera.
This operation therefore becomes spontaneous both during defecation and during the lifting of a heavy load.
During the Valsalva maneuver the synergic contraction of the abdomen and other expiratory muscles transforms the abdominal cavity into a real inflatable chamber, enclosed by very rigid and resistant walls.
Some studies have shown that this action reduces the pressure acting at the level of the T12-L1 intervertebral disc and 30% at the level of the L5-S1 disc by up to 50%.
In weight lifting, in bodybuilding, or in exercises where the load acts mainly on the spinal muscles and on the lumbar vertebrae (squats, half detachments, flexed rowers etc.). it is therefore necessary to remember not to apply the normal advice on breathing. Exhaling during the initial contraction phase would have the opposite effect and would considerably increase the risk of disc herniations and other column injuries.
The state of absolute apnea that is created, however, is the cause of some temporary, but important, cardio-circulatory changes. The increase in intrathoracic and intra-abdominal pressure, associated with the contraction of the other muscles used to lift the load, causes a decrease in the venous return to the heart, which is also forced to carry out its action of contraction and relaxation against high resistances.
This maneuver can therefore be potentially very harmful for those suffering from cardiac and / or circulatory problems (hypertensive, infarcted, diabetic in advanced stages of the disease etc.). In this case the exercises listed above must absolutely be avoided; instead, we will try to improve the lifting technique (bent knees and upright chest) by associating it with postural control exercises that can have beneficial effects in everyday life (see: Functional exercises).
