A new study reports that walking for just 30 minutes a day can create an anticancer environment in the blood and suppress the growth of breast cancer cells. These findings are particularly significant for younger women, in whom breast cancer tends to progress more rapidly and aggressively.
A research team led by Linda Laizane, a PhD candidate in medical biochemistry at Riga Stradins University in Latvia, analyzed how aerobic exercise affects anticancer-related proteins, or biomarkers, in the blood of 18 healthy premenopausal women with an average age of 41.
For the study, blood was collected immediately after participants performed treadmill walking at various intensities. The researchers then evaluated the effects of that blood on cancer cells, specifically focusing on changes in "myokines"—proteins secreted by muscles during physical activity.
Exercise Intensity Linked to Stronger Anticancer Activity
The results demonstrated that even 30 minutes of low-intensity walking triggered anticancer-related changes in the blood, reducing the rate of cancer cell proliferation. As the intensity of the exercise increased, these protective effects became more pronounced. When participants engaged in moderate-to-high-intensity exercise for 30 to 45 minutes, increased anticancer activity was confirmed in approximately half of the biomarkers studied.
The researchers verified these effects by directly exposing blood collected immediately after exercise to HER2-positive breast cancer cells, a subtype known for its aggressive nature. In a blood environment rich in exercise-induced myokines, the rate of cancer cell division decreased significantly.
HER2 is a protein on the surface of breast cells that regulates growth and repair. However, genetic abnormalities can cause an overproduction of this protein, leading to excessive cell division and tumor formation. Approximately 15% to 20% of all breast cancer patients are diagnosed with the HER2-positive subtype.
Practical Habits for Long-Term Prevention
The researchers explained that while these findings reflect the immediate biological response to a single bout of exercise, they support growing evidence that physical activity contributes to both breast cancer prevention and the slowing of disease progression.
"Even just 30 minutes of high-intensity exercise can activate anticancer factors in the blood, and consistent exercise is vital to maintain this state," said Linda Laizane. "Even if visiting a gym is difficult, simply increasing your everyday walking pace can be a practical way to induce these anticancer effects."
According to the research team, exercising at a moderate intensity or higher for 30 minutes a day, five times a week, may help consistently maintain beneficial levels of myokines and hormones in the blood. However, they emphasized that further research is required to determine the long-term clinical significance of these findings. This study was presented at the 15th European Breast Cancer Conference held in Barcelona, Spain.
