Trying to lose weight often starts with the same promise many of us make to ourselves: this time I’ll stick to it. Maybe it begins with a few longer walks, a gym membership, or a renewed focus on healthier meals. But after the initial motivation fades, one question usually remains: how much exercise is actually needed each week to see meaningful results?
Recent research offers a clearer answer. Scientists studying the relationship between physical activity and weight loss have identified a threshold that seems to make the biggest difference for people trying to reduce body weight and body fat.
150 minutes of physical activity per week may be the key to weight loss
A large scientific review published in December 2024 in JAMA Network Open examined the impact of exercise duration on weight management. Researchers analyzed 116 randomized clinical trials involving a total of 6,880 adults who were overweight or living with obesity.
Participants followed aerobic training programs including activities such as walking, running, or swimming, with weekly exercise durations ranging from about 55 minutes to 300 minutes.
When scientists compared the outcomes, they noticed something interesting. Even a modest amount of exercise — roughly 30 minutes of aerobic activity per week — produced small improvements in body weight, waist circumference, and body fat levels.
However, the most meaningful progress appeared at a higher threshold.
According to epidemiologist Ahmad Jayedi of Imperial College London, the study’s lead author, the data suggest that “at least 150 minutes per week of moderate-intensity aerobic exercise is needed to achieve clinically meaningful weight loss,” he explained in comments reported by The Guardian.
In practical terms, that means about 2 hours and 30 minutes of exercise per week. Spread across several days, this could look like a brisk 30-minute walk five times a week or a combination of cardio sessions and other activities.
Researchers also observed that this amount of weekly exercise was linked to significant reductions in waist circumference and body fat, two indicators strongly associated with long-term health outcomes.
Which types of exercise work best for losing weight?
One of the most reassuring findings from the research is that there is no single “perfect” activity. The most effective exercise is often simply the one that fits naturally into everyday life.
Walking and running, for example, remain among the easiest ways to build a consistent routine. A quick walk during lunch breaks or choosing the stairs instead of the elevator may not feel like a workout at first, but over time these habits contribute to sustainable weight loss.
Strength training can also play an important role. Fitness coach Ronny Garcia told Eat This, Not That! that strength-training sessions lasting 30 to 60 minutes can support weight loss by building muscle and increasing the body’s metabolic rate.
Public health guidance points in the same direction. The World Health Organization (WHO) recommends that adults aim for at least 150 minutes of moderate-intensity activity per week, or 75 minutes of vigorous activity, to maintain good health. This level of activity not only helps with weight management but also reduces the risk of cardiovascular disease, certain cancers, and obesity.
In real life, this often means finding simple ways to move more consistently. A friend of mine once started with a modest goal: walking around the neighborhood every evening after dinner. Within a few months, those walks became a daily ritual — and without strict dieting, the scale slowly began to shift.
That may be the real lesson behind the numbers. When it comes to effective weight management, consistency matters far more than extreme workouts or short-lived diet plans. Small, regular habits — repeated week after week — tend to produce the results that last.
