Training for the heart.
Text: Andreas Grote
Sports and physical activity are known to help reduce blood pressure. The specific exercises that are most effective in achieving this goal have been explored by researchers in Basel as part of a European initiative.
Excess blood pressure persists as one of the major lifestyle diseases of the modern age, although its causes are well known: An unhealthy lifestyle resulting in excess weight, poor nutrition, lack of exercise, stress or smoking all contribute to rising blood pressure over the years. This often unnoticed phenomenon can be further exacerbated by a genetic predisposition. In the long term, it can be particularly damaging to the vessels that make up the cardiovascular system. Statistically, around one in four heart attacks can now be attributed to excessive blood pressure, while experts estimate that as much as 60 percent of the world’s population could suffer from hypertension (the medical term for high blood pressure) within the next five years.
Hypertension can be alleviated with the help of drugs, but this often leads to unwanted side effects. Studies have long shown that regular physical activity favorably affects blood pressure. This research has focused on the diagnosis of hypertension in general terms, however, without taking into account patients’ actual blood pressure level going into treatment.
More is better
Sports medicine physician Henner Hanssen and his colleagues at the Department of Sport, Exercise and Health are therefore looking for new ways to reduce blood pressure as effectively as possible with the help of physical exercise. To this end, they began by reviewing existing metastudies in collaboration with experts from the European Association of Preventive Cardiology to determine which kind of training has the greatest impact on different blood pressure levels. In this way, training plans can be tailored to the particular blood pressure level of each patient. “This systematic survey of the literature is the first study of its kind anywhere in the world,” says lead researcher Henner Hanssen.
The basic recommendation for all forms of training is to train at moderate intensity for at least 15 minutes a day, ideally 30 minutes five times a week. Moderate intensity means breaking a mild sweat while remaining able to maintain a conversation, or reaching around 70 percent of one’s maximum heart rate. But, as Hanssen says, “it’s not one-size-fits-all. From our results, we can conclude that exercise should be prescribed on the basis of the initial blood pressure level of each individual patient.”
The studies showed that for high blood pressure (≥ 140 mmHg systolic and ≥ 90 mmHg diastolic), classical endurance training like power walking, brisk walking, cycling or swimming reduced blood pressure by 7.4 mmHg (systolic) or 4.5 mmHg (diastolic) on average. “That’s just an average, however – some patients manage a reduction well in excess of 10 mmHg,” Hanssen reports. Moreover, the studies revealed a link between dose and effect, he adds: The higher the volume of moderate intensity training performed, the greater the reduction.
For high-normal blood pressure (130 –140 mmHg systolic, 85–90 mmHg diastolic) meanwhile, the greatest reduction is achieved with dynamic strength training. Dynamic refers to movements in which the muscles contract to overcome some form of resistance. One example is weightlifting, but the resistance can also be the person’s own bodyweight, as with climbing stairs or performing squats or pushups. This kind of activity was found to reduce systolic blood pressure by 4 mmHg, and diastolic blood pressure by 3.4 mmHg.
Making training a part of everyday life
For people whose blood pressure is still in the normal range but are at increased risk of high blood pressure due to obesity or genetic predisposition, isometric strength training seems to be the best choice. This kind of training consists of holding exercises such as planks, side planks or – for those with reduced general mobility – a grip trainer. In these exercises, the muscle is placed under strain, but is only tensing rather than contracting. According to the studies, exercising in this way lowered systolic pressure by 7.2 mmHg and diastolic pressure by 2.6 mmHg.
“In principle, these exercises are beneficial to virtually all patients,” says Hanssen. Nevertheless, a lasting reduction in blood pressure can only be observed after around four to eight weeks at the earliest. Moreover, success is heavily dependent on how committed the patient remains. If they don’t stick to the program, their blood pressure goes back up, just as with patients that fail to take their blood pressure medications. “In other words, regular training has to be a lifestyle choice for the long haul,” Hanssen explains.
Henner Hanssen and his colleague Lukas Streese are already working on the next step, the HyperVASC study. This project aims to find out how high intensity interval training (HIIT) affects blood pressure and vessels compared to moderate intensity training. “This approach could have the potential to reduce blood pressure even more effectively.”
Medical supervision advised
In contrast to drug treatments, there are no side effects to be expected from physical training, Hanssen says. Nevertheless: “Being overly enthusiastic and ramping up the intensity too soon can take its toll on bones, joints and tendons,” he warns. To help patients get off to a good start and stay on course, the ideal approach would be for doctors to prescribe individual exercise plans. “But there aren’t enough exercise therapists in Switzerland for that.” Institutes offering this kind of support, such as the University of Basel’s Department of Sport, Exercise and Health, can currently be counted on the fingers of one hand, he adds. In the meantime, anyone planning to undertake exercise therapy autonomously should get a medical check-up and have their blood pressure measured first. It is also a good idea to see a specialist doctor or exercise therapist every three months to discuss any difficulties encountered while training.
Precisely why certain kinds of training are more effective than others at reducing blood pressure remains unclear. Hypotheses have been put forward, however. “In general, the body reacts to high exercise load and exertion by increasing blood pressure,” Hanssen explains. As a result, training gives the body an incentive to keep blood pressure lower throughout the day when it is at rest. Hanssen therefore recommends taking the stairs rather than the elevator, or catching the bus instead of driving and getting off a stop earlier to walk the rest of the way to work. “Besides lowering blood pressure, this also boosts blood vessel health.” And lower blood pressure is not the only benefit to be gained from regular exercise, of course. “Training has also been proven to have a positive impact on overall fitness and fat and blood sugar levels, aside from the social aspects,” Hanssen notes.
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