Hemodynamic effects of strength exercises

Strength exercises may impose an extremely heavy cardiovascular load due to increased heart rate and a high increase in blood pressure. For this reason, despite its proven efficacy, patients who would benefit from strength training were directed away from it. The magnitude of heart rate and blood pressure increases evoked by strength exercises depend mainly on the ratio between strength developed and maximal strength, and on the number of repetitions of a given exercise. The attitude to this form of training over the last two decades changed to such a point that strength training became recommended even for cardiac patients. Nevertheless adverse effects of strength training have to be taken into account: several cases of cerebral hemorrhage during strength training in apparently healthy young subjects have been registered. It seems desirable to assess individual response of cardiovascular system to strength exercises, to this end it might be useful to better understand the mechanisms of this response. However at present relevant data is scarce and inconsistent. Of special interest is the interpretation of the role of Valsalva effect, which is spontaneously performed while exercising with very heavy loads. This maneuver on one hand adds to the rise in arterial pressure and on the other may create a protection against the rise of transmural pressure acting on heart’s and brain arterial vessel walls.