A new study shows that very short, intense exercise may cause more immediate changes in the body than longer, moderate workouts. The study was done by scientists who divided 19 healthy young men into two groups. One group did six short, hard sprints on a stationary bicycle, while the other group cycled at a steady, moderate speed for 90 minutes. After the exercise, the scientists tested the men’s blood. They found that the men who did the short sprints had bigger and faster changes in important proteins compared to those who cycled for a longer time.

The main reason for these changes is the intensity of the exercise. Intense exercise, like sprinting, pushes the body much harder in a short time. This makes the body react more quickly and strongly, especially in how it rebuilds tissue and grows new blood vessels.

Because of these findings, some scientists think that short, intense workouts might help people who do not have much time to exercise. However, the researchers say we need more studies to know if these fast changes are really better for health over a long period.