Overtraining Leads To Greater Impulsivity

Physical activity has many benefits for the body and mind. Thanks to it, we improve physical conditioning, muscle strength and tone, the cardiovascular system and even our cognitive capacity. However, over-exercising or overtraining can also lead to a number of negative consequences.

Among the problems you may have with overtraining and not resting for the necessary time, we can mention addiction to certain sports, such as vigorexia or runnorexia, muscle injuries, heart and respiratory problems, weakened immune system, aging of joints and the so-called overtraining syndrome.

overtraining syndrome

Occasionally, overtraining moves to a higher level, leading to overtraining syndrome. This syndrome is similar to the burnout that occurs in workers.

Therefore, there is a sharp drop in the performance of athletes, even when they are at rest, accompanied by a series of physical and psychological symptoms.

Among its symptoms, it is possible to differentiate between physical and mental overtraining:

physical overtraining

The physical and physiological symptoms that can appear in this syndrome are:

• Increased blood pressure and heart rate.
• Increased body temperature.
• Hypertension.
• Weight loss and appetite.
• Gastrointestinal problems.
• Muscle aches.
• Vulnerability to infections and reduced immunity.
• High cortisol.
• Increased fatty acids.
• Decrease in iron, hemoglobin and/or glycogen.

mental overtraining

In addition to the above symptoms, the following psychological symptoms occur:

• Mood changes.
• Fatigue and exhaustion.
• Anxiety.
• Irritability.
• Lack of concentration.
• Low self-esteem and confidence.
• Loss of libido.
• Sleep disorders.

Also, a recent study found that overtraining can lead to increased impulsivity. This fact does not affect this characteristic in a simple way, but it can have very negative consequences on behavior and health.

The study

In September 2019, a group of French researchers published an investigation into the consequences of excessive training on impulsiveness. Specifically, how overtraining affects cognitive control.

For this, they recruited a total of 37 triathletes, who were divided into two groups: overtraining and control group. That is, 19 of them increased the training duration by 40% in each session for three weeks. The other 19 were supervised in normal training during the same period.

Thus, after the experimental weeks of training (usual or overloaded intensity), the participants were submitted to an evaluation session. This session was divided as follows:

• For 50 minutes, inside a functional MRI machine, they performed cognitive control tasks interspersed with three decision-making, where they had to choose between two financial rewards: one more immediate and another long-term.
• A 45-minute cycling session at full speed to trigger the effects of overloaded training, seeking out fatigue.

• Another 50 minutes in resonance, performing the same cognitive tasks and decision making as in the first block.

In this way, the researchers looked at the excitability of the cerebral cortex, performance on specific tasks and the preference for immediate or delayed rewards.

What did they find?

The researchers were interested in the activity of the cerebral cortex related to impulsivity and the results of the temporary decision task. In addition, cognitive tasks were included, mainly, to trigger the activation of that brain area.

Thus, comparing brain activity after 45 minutes of exercise with activity in the first part of the session, they found a decrease in lateral prefrontal cortex activity during decision-making, not in cognitive performance.

This would mean that overtraining has a negative effect on tasks in which a decision must be made subjectively, consuming resources and making the task more difficult.

In this task, they observed that overtrained triathletes showed a greater preference for smaller but short-term rewards compared to the control group who maintained their normal level of exertion.

implications

These results are relevant in several respects. On the one hand, cognitive control, as opposed to impulsiveness, helps us to perform tasks in a targeted and conscious way.

In the practice of exercises, less cognitive control would provide a greater sense of security, pushing the body to greater limits. Thus, not stopping, not resting when necessary or valuing a more immediate reward, can lead the athlete to injuries and riskier behaviors.

On the other hand, this preference for getting the best in the present moment is related to doping. An adulteration of the organism that, in addition to compromising long-term goals, has direct consequences for physical and psychological health.

In summary, as with most activities, accumulated fatigue due to overtraining can have both short-term and long-term negative consequences. Therefore, it is important to promote healthy habits, which should include learning to make appropriate decisions and knowing how not to push our body and mind to the limit.