1. Why Do Your Shoulders Tense Up Before a Presentation?
Tension is almost a reflex. While waiting for your turn to speak, you might notice your shoulders have risen or your hands are clenched. Many people have this experience. The American Psychological Association explains that muscle tension is a nearly reflexive response to stress, serving as a way to protect the body from injury and pain. [4]
When sudden stress occurs, muscles tense up all at once. It is easy to imagine that the body is preparing so it can move quickly if something happens. The key point here is that you are not consciously deciding to tense up; your body starts this process automatically. [4]
How is this "bracing" prepared inside your body? [4]
2. How Does the Body Prepare to Fight or Run Away from Danger?
When an animal encounters danger, the choice to fight or flee is needed instantly. The physiologist Walter Cannon discussed how animals react to fear by activating the sympathetic nervous system. During this reaction, blood vessels leading to the muscles widen, making it easier to generate force. [1]
The sympathetic nervous system increases blood supply to skeletal muscles during movement. In times of crisis, heart rate, breathing rate, and blood pressure rise, putting the body in an excited state. [2] [3]
In contrast, the parasympathetic nervous system plays an important role during rest. It lowers the heart rate and reduces blood pressure. During rest, the breathing rate also decreases. These two nerves work in balance to regulate the body. [2] [3]
So, in what situations does the side that releases tension actually work? When danger passes, what happens next? [2]
3. When Does Muscle Tension Loosen After Stress Goes Away?
According to the American Psychological Association, muscles loosen their tension when stress goes away. Feeling relaxed and letting go of strength is connected to the release of this brace against danger. [4]
There is a continuation to this explanation. If stress lasts a long time, muscles can remain in a constant state of bracing. The explanation that muscle tension loosens when stress disappears connects to the sensation of feeling relief. [4]
Is there a way to relax your muscles on your own? One clue lies in the sigh. [4]
Understanding this helps build the idea that feeling relaxed corresponds to a change in the direction of releasing the brace against danger. [4]
4. Does Muscle Tension Drop After a Natural Sigh?
Sighs are said to occur both when you are troubled and when you feel relief. [7] Researchers from the University of Leuven in Belgium and other institutions investigated body changes after sighs in 2010. In the experiment, after a naturally occurring sigh, the value of the electromyogram (a measure of muscle tension) dropped. They reported that the drop during recovery was smaller when the sigh was instructed rather than spontaneous. [6]
The psychological role of the sigh is still not well understood. In a separate experiment by the Belgian researchers in 2009, more sighs occurred during the relief period after stress, such as loud noises, than during the stress itself. Sighs have a function of resetting breathing, but their psychological role is not yet clear. [7]
Also, the electromyogram results came from a laboratory experiment involving tasks that caused psychological stress. This does not mean that sighing always guarantees that strength will be released. [6]
If a sigh can be a trigger for releasing the body’s brace, can we achieve something similar by consciously tensing and then releasing our muscles? [6]
5. What Is Progressive Muscle Relaxation?
Progressive muscle relaxation is a practice developed by Edmund Jacobson. It involves closing your eyes, repeating the tension and relaxation of muscles, and focusing your awareness on the state where the most strength has been released. [5]
The US National Center for Complementary and Integrative Health (NCCIH) describes these relaxation methods as practices that cause a "relaxation response," where breathing slows down and blood pressure and heart rate decrease. Progressive muscle relaxation is a method of tensing muscles and then loosening them. [8]
However, the NCCIH evaluates the effects for each purpose. They note that many related studies have limited quality, and the effects are modest. They do not summarize all relaxation methods into a single evaluation. [8]
It is better to view this not as a cure-all, but as a practice to try and notice differences. There is a form you can try within a comfortable range, which is described in the next section. [8]
6. Can Shrugging and Dropping Your Shoulders Help You Notice Tension?
Try this: Sit in a chair and slowly lift your shoulders as if bringing them close to your ears. Count to 5, then let them drop, releasing the tension. If you feel pain, stop immediately. Compare the weight and warmth of your shoulders after dropping them to how they felt before lifting them. [8]
It is also interesting to notice how your shoulders and hands feel after a natural sigh that comes when you feel relief. Since the effects of this method are considered modest, the goal of the observation is not "whether it works," but "whether you can notice that you had been tensed up." [8]