In a fast-paced world filled with work pressures, family duties, and endless to-do lists, finding time for exercise can be a challenge, let alone meeting the recommended weekly amount. Currently, less than 25% of Americans adhere to national physical activity guidelines, which advise adults to engage in at least 150 minutes of moderate-intensity exercise (e.g., brisk walking, gardening, doubles tennis) per week or 75 minutes of vigorous-intensity exercise (e.g., running, swimming laps, hiking uphill), along with two days of strength training.
New Research Offers Hope
A recent study from the Norwegian University of Science and Technology indicates that you may not need to exercise as much to reap health benefits, provided the activity is intense. Researchers discovered that just 30 minutes of high-intensity exercise per week can significantly improve health, particularly heart health.
Optimal Exercise Distribution
For maximum benefit, researchers recommend splitting the 30 minutes across the week. For example, 7.5 minutes of vigorous exercise four times a week. The benefits, such as better blood pressure and blood sugar control, last one to two days after exercise, making multiple sessions throughout the week ideal. The study emphasizes that this high-intensity exercise must elevate heart rate and cause breathlessness; low-intensity yoga or leisurely walks do not suffice.
Dr. Jason Tso, a cardiologist and medical director of the Sports Cardiology Program at Stanford University School of Medicine, noted, “Hard activity for someone who’s inactive feels like a lot and can be tough.” Tso, who was not involved in the study, underscores the challenge.
Defining High-Intensity Exercise
Researchers define high-intensity exercise as reaching at least 85% of your maximum heart rate or movement that makes talking comfortably difficult but allows short sentences. Common examples include spin classes, running, or singles tennis. However, what causes breathlessness varies by fitness level; for some, it’s a fast trail run, for others, a slow jog.
Dr. Sawalla Guseh, director of the Cardiovascular Performance Program at Mass General Brigham Heart and Vascular Institute, cautioned via email, “Vigorous activity places real demand on the heart. For inactive individuals or those with risk factors like high blood pressure, diabetes, or a family history of heart disease, it’s wise to consult a clinician before starting intense exercise.”
More Bang for Your Buck
While 30 minutes per week is far less than the recommended 150 minutes of moderate or 75 minutes of vigorous exercise, the official guidelines are based on large-scale population studies. Tso explained, “There’s been work showing shorter, very high-intensity exercise provides similar cardiovascular benefits. This indicates that even small amounts of activity yield significant benefits.”
Guseh added, “For a sedentary person, small amounts of vigorous activity can improve cardiovascular fitness and risk factors.” However, high-intensity exercise is demanding and not suitable for everyone. “Higher-intensity exercise is more time-efficient, burning more calories and offering more bang for the buck at lower time commitments,” Tso said, “but there’s a trade-off.”
Is a Few Minutes Enough?
Before committing to a five-minute daily workout, note that it may not be as beneficial as longer sessions. Guseh stated, “I would not present 30 minutes per week as the final goal. Evidence supports a dose-response relationship: more regular physical activity generally provides greater cardiovascular benefit, up to a point.” Tso added, “Five minutes a day of vigorous activity is much better than nothing, but whether it’s enough is a big question.”
More research is needed to compare short high-intensity exercise with longer sessions. “I wouldn’t anchor on this one study, but it reinforces that everyone should do something,” Tso said. Guseh cautioned, “People who can do vigorous exercise are often healthier and fitter to begin with, which is a limitation of the research.”
Exercise: As Effective as Medicine
Regular exercise offers countless health benefits. “It changes the heart and vascular system, lowers blood pressure and cholesterol, increases heart size, and boosts energy,” Tso explained. It also improves mood, reduces anxiety and depression, strengthens bones, lowers cancer risk, maintains muscle, and enhances sleep. “Doctors prescribe medicines, but exercise is probably as effective as several medicines,” Tso emphasized.
Exercise should be part of everyone’s lifestyle. Inability to commit to hours of weekly exercise should not deter activity. “Everyone can stay as active as possible,” Tso said. Many focus on the “best” workout for the “optimal” time, which can be a barrier. If you only have time for a 10-minute walk, do it—it’s infinitely better than being sedentary. “For the general population, just do something and do it regularly,” Tso said.
Guseh concluded, “Thirty minutes is a meaningful starting point, not the destination. Start where you are, build gradually, know your risk, and make the goal a sustainable exercise habit.”
