Isometric hand grip training: a natural hypertensive therapy.

Introduction

The measurement of blood pressure is often a stressful event for many patients. During an annual check-up or trip to the local pharmacy, patients commonly experience symptoms of anxiety while waiting to have their blood pressure taken. Anxiety symptoms are likely invoked by the knowledge of the negative health risks associated with high blood pressure. Chronic elevation of blood pressure, known as hypertension, is linked with increased mortality and morbidity and is a major modifiable risk factor in cardiovascular disease. (1) Hypertension is estimated to affect nearly one billion people worldwide and is frequently termed the "silent killer," since it often presents with no apparent symptoms. (1,2) In 2001, the total estimated costs associated with treating hypertension in the United States exceeded 50 billion dollars. (3) A recent investigation into the effectiveness of current pharmacological treatments for hypertension has demonstrated their inadequacy to control approximately 47% of affected hypertensive patients. (4) The failure of currently accepted treatments for hypertension in a large percentage of individuals has resulted in the need for effective and cost-efficient, non-pharmacological, hypertensive treatments. One promising treatment, currently being explored, is isometric hand grip exercise training (IHG). This review offers a brief introduction to isometric hand grip training and its relevance as a non-pharmacological, antihypertensive treatment alternative.

Hypertension

The most recent definition of hypertension describes "normal" as arterial blood pressure below 140/90 mmHg. (5) Using this criterion, prevalence rates for high blood pressure are approaching one in three in the general population.1 Recent guidelines also describe blood pressure values ranging between 130-139 / 80-89 mmHg as "high normal" and at increased risk for developing hypertension. (5) As mentioned, hypertension is particularly dangerous due to the lack of associated symptoms and visible signs. This absence of symptoms leaves approximately 30% of affected individuals unaware of their untreated condition. (6) While hypertension is most often managed by medications, alternatives such as exercise, diet modification, weight reduction, smoking cessation, and further lifestyle changes often produce positive results. (1,5)

Meta-analyses of numerous randomized controlled trials in normotensive and hypertensive participants have established blood pressure reductions of 3.4/2.4 mmHg (systolic/diastolic) and 5.9/4.2 mmHg with aerobic exercise and diet modification, respectively. (7,8) The largest reductions of 7.4/5.8 mmHg were observed in hypertensive participants. (8) Aerobic exercise and diet modification…