How Does the Body Adapt to Exercise?

By Aaron Eisberg

General Adaptation Syndrome (GAS)

Human beings by definition are adaptation machines. Our entire being, Mind, Body and Spirit, is able to meet challenges presented in our environments and adapt and overcome these challenges for the purpose of survival and thriving. A major mechanism in this process is the Fight, Flight or Freeze mechanism. A more colorful way of stating it is What Does Not Kill You Makes You Stronger! Exercise is very much part of this process, it is technically a form of stress. When a trainer/coach is doing their job
properly they are Applying Thoughtful Stress and Recover.

The process of adaptation due to stress is known as General Adaptation Syndrome (GAS). The human form wants to maintain Alostatsis, which is a little bit more complex than Homeostasis. Alostasis is where there is balance biologically, emotionally, and mentally.

Phase One (1) is the base-line where there is balance. When a stressor is introduced, the body first reacts to this stress by entering the Alarm Stage - the “flight or fight” stage where the body prepares for physical & mental demands. Body temperature and blood pressure both decrease. Loss of fluid from body tissues also occurs. Heart rate and blood pressure increase as stress hormones and adrenaline are released.

Phase Two (2), the Compensation Stage, is where your system tries to meet the demands of the stressors where they are present.

Phase Three (3) is the Resistance Stage where the body engages the demands in order to cope with the stress and is biologically adapting to make sure the next time a similar stress is encountered it will be better prepared to survive. If the stressful situation is resolved, the body will continue to repair itself until it returns to its pre-stress state.

Phase Four (4), the Exhaustion or Decompensation Stage, is where the stress persists and the body's resources are depleted. This stage occurs during prolonged or chronic stress when the body’s adaptation to higher stress levels starts to break down. The body no longer has the strength to fight the stress that it is experiencing. In this stage, symptoms such as trouble sleeping, fatigue and depressed mood are very likely to occur.

For the most part, when someone is spending time in the alarm stage, this is not a harmful experience. It is a natural state designed by your body to protect it danger. However, when prolonged or chronic stress is present, the body may not be able to repair itself in any timely manner and will be susceptible to exhaustion.

Understanding these stages can really help individuals to better manage their stress levels, which can lead to a healthier and more active lifestyle.

General Adaptation Syndrome (GAS)

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