However the core work is essential for good performance in many sports. Studies have been shown that a good core state can improve performance by as much as endurance sports. In one particular study, we performed an intervention in competitive and recreational runners of 5,000 meters.
This intervention was conducting a training program the middle or core for 6 weeks. The results were an increase in performance in the 5,000-meter distance but no improvement in strength or lower body stability.
The main reason which is thought to occur because performance improvement is core to the work of more efficient running technique. Furthermore, the study investigators speculated that a training program longer would probably have more benefits.