London Marathon - London, Britain - Ellie Griffin and Charlie Muddyman in action during the marathon REUTERS/John Sibley
High blood pressure occurs when the force of blood against the walls of the arteries is consistently too high. This can cause damage to the arteries and lead to serious health problems such as heart disease, stroke, and kidney disease. Blood pressure is measured in millimeters of mercury (mmHg). It is recorded as two numbers: systolic pressure (the pressure when the heart beats) over diastolic pressure (the pressure when the heart rests between beats). A normal BP reading is 120/80 mmHg. The threshold is slightly different in different countries, but typically, hypertension is diagnosed when a person’s BP readings consistently exceed 140/90 mmHg during multiple measurements taken over time. Successfully controlling hypertension involves ensuring that BP levels are managed effectively, which remains a significant challenge globally.
Why Should We Care?
Medical practitioners refer to hypertension as the "silent killer" because most people with elevated BP don’t experience any symptoms. Across the world, only about half of those with hypertension are aware of it, yet less than a quarter have their BP under control(1). Blood pressure above optimal levels is linearly associated with an escalated risk of heart disease. With at least half of the world population unaware of their hypertension status, even an incremental advancement in population awareness and subsequent action could save millions of lives.
The good news for athletes is that exercise lowers blood pressure and boosts long-term survival from heart disease. Physical activity lowers death rates due to heart disease over time. It is not surprising that physical exercise is a cornerstone in the non-drug therapy for individuals with prehypertension (i.e., systolic BP between 130 and 139 mmHg and diastolic BP between 85 and 89 mmHg) and hypertension (i.e., systolic BP ≥ 140 mmHg and diastolic BP ≥ 90 mmHg). Although clinicians recommend exercise to manage hypertension, there is debate on which type is most effective. Aerobic exercise is the most common recommendation and includes activities that increase heart and breathing rates for an extended period, such as jogging or running.
However, there is a range of exercise types that clinicians can prescribe when managing patients with hypertension. Depending on the program’s target, clinicians can prescribe them in isolation or combination. They include:
1. High-intensity interval training (HIIT)
Which is alternating between short bursts of intense exercise and periods of rest or lower-intensity activity.
2. Aerobic interval training (AIT)
Similar to HIIT, AIT involves alternating between moderate to intense aerobic activity for longer periods with short periods of rest or lower-intensity activity.
3. Isometric exercise training (IET)
Muscle contractions without muscle length or joint angle. For example, wall sits, planks, etc.
4. Dynamic resistance training (DRT)
Continuous movement against an opposing force. Dynamic resistance training exercises include bicep curls, squats, lunges, and bench presses.
Researchers at Canterbury Christ Church University in the United Kingdom conducted a systematic review and network meta-analysis of 270 randomized controlled trials, attempting to evaluate the effects of all relevant exercise training modes on resting blood pressure to identify pragmatic anti-hypertensive exercise recommendations(2).
The researchers followed PRISMA guidelines and utilized a comprehensive search strategy across PubMed, Cochrane Library, and Web of Science, with PROSPERO registration—studies meeting inclusion criteria. The researchers included the data that provided baseline and post-intervention blood pressure values. Furthermore, they categorized the exercise protocols and stratified the analyses by baseline blood pressure levels.
The authors found a significant reduction in resting systolic and diastolic BP following all exercise modes except AIT alone. In general, the effects were greater in people with hypertension than in those with normal baseline blood pressure. Then, the authors ranked the order of effectiveness of different exercise modes (see table 1).