This note summarises a published meta-analysis by George Kelley and Kristi Kelley. A longer plain-language explanation is in our article What the research says about isometric handgrip exercise.
What the researchers did
The authors searched five databases for randomized controlled trials published between 1971 and 2009 in which adults performed isometric handgrip training for at least four weeks and resting blood pressure was reported. Of 287 studies reviewed, three met the criteria, with 81 participants in total: 42 who trained and 39 controls. Both authors coded each study independently and the data were pooled with random-effects models.
What they reported
Across the three trials, resting systolic and diastolic blood pressure at the end of training were about 10 percent lower in the exercise groups than in the control groups, a pooled difference of 13.4 mmHg systolic and 7.8 mmHg diastolic. The results were similar under fixed-effects models.
What the authors cautioned
The pooled sample was small, only three trials qualified, and all measured blood pressure in a clinic setting rather than with ambulatory monitoring. The authors called for larger trials before firm conclusions are drawn.
How to read this
The analysis concerns isometric handgrip exercise as a category of exercise performed under study conditions. It is not a study of any product and says nothing about what an individual should expect.
This is a summary of a published study, provided for general education. It is not medical advice and it is not a claim about any product. The Zona Plus is a handheld isometric exercise device intended for adjunctive use in the maintenance of overall cardiovascular wellness; it is not intended to diagnose, treat, cure or prevent high blood pressure or any disease. Talk with your physician about your blood pressure and before starting any exercise program.
