A study by a Norwegian team of scientists has shown that high-intensity exercise may be beneficial for patients with coronary heart disease, in spite of the prevailing belief that patients with heart disease should only participate in moderate-intensity exercise in order to protect their hearts.
The study examined data from four randomized controlled trials conducted at the Center of Exercise in Medicine at the Norwegian University of Science and Technology. It included a total of 112 participants who had coronary heart disease and lasted for 12 weeks. During those 12 weeks, the participants completed a 4x4 exercise model in which they did 4 minutes of high-intensity exercise followed by 3 minutes of moderate intensity exercise repeated 4 times. The researchers measured the participants’ heart rates during exercise and their VO2max, or peak oxygen uptake, before and after the exercise period.
The results showed that the intensity of training had a significant impact on improvements on VO2max, while number of sessions, age, and baseline fitness had no impact. The greatest improvements were seen when participants exercised at an intensity that was more than 92% of their maximum heart rate. Importantly, the trials also showed that very intense exercise was safe for people with coronary heart disease, which had previously been in question.
The authors noted that pushing yourself over 90% of your maximum heart rate may save you from doing an extra exercise session during the week, since it has a greater impact on improving your fitness. However, they also noted that any exercise is better than none, so getting yourself to the gym or running track is more important than reaching a specific heart rate during your session.
Sources: Science Daily