Submaximal speed of team athletes deteriorates just after a mentally exhausting task. They opt for a lower running speed than when they have not performed a mentally fatiguing task. The performance in intensive sprints and the maximum running speed are not affected by mental fatigue.
After a long period of heavy cognitive activity cognitive fatigue (also called mental fatigue) can occur. This can lead to a temporary deterioration of the cognitive performance and an increase in the feelings of fatigue. These feelings of fatigue may affect the endurance performance negatively . Recent research shows that mental fatigue did not affect explosive sports performance. If mental fatigue affects the performance in team sports is not known. Smith and colleagues have investigated the effect of mental fatigue at the interval performance at 10 team athletes.
In this study 10 team athletes participated from football, rugby and hockey with an average 22 years and a VO2max 48 ml / kg.min. They underwent twice the same physical test which consisted of a warm-up of 5 minutes followed by an intensive test interval of 15 times 3 minutes on a non motorized treadmill. This treadmill was driven by the athletes themselves; they also determined the exact running speed themselves. With this test, the researchers tried to simulate the effort during a team sport. The athletes had to run in a pre-established sequence alternately at an intensity of 20%, 35%, 50%, 70% or 100% of their maximum running speed. Prior to the physical test athletes had to perform either a 90 minutes mentally exhausting computer task (AX-CPR), by pressing a button when they saw a specific series of letters on the screen, or watching an emotionally neutral documentary.
The results showed that the athletes felt more tired after the mental test than after the control situation (9 vs. 5 on a scale of 0 to 16). Their average running speed during the test was lower after the mental task, and that is why they made a total distance less after the control situation (4072 m vs. 4163 m, a difference of 2.8%). This was because of their sub-maximal running speed was lower than in the control situation (1.28 m / s vs 1.31 m / s). The peak speed and running speed during intensive sprints were the same in both conditions. There were no differences in the maximum heart rate.
This study shows that athletes choose for lower sub maximal running speed if they are mentally fatigued. However, the differences are not large. The sprint speed is irrelevant to the mental fatigue. Especially high sprint speed is important for a team sport performance. Nevertheless, it may be useful for athletes to avoid mentally exhausting jobs just before an important match.