Our physiological system (body) responds to appropriate stimuli (stress). Repeated adequate stress to the body accompanied by adequate recovery leads to adaptation, resulting in improved functional capacity. The sole purpose of the training session is to stress the body so that it results in adaptation to that stress. With inadequate stress and recovery (rest and nutrition) no adaptation will occur, while conversely too much stress will result in injury or overtraining.

However, it is very important to recognize the capabilities and limitations of the body in order to introduce adequate stress. Without understanding human anatomy and exercise physiology nobody will ever know how, when and how much exercise stress to introduce, and will therefore never understand the process of evaluating the body’s response to the exercise stress. We get to witness the unfamiliarity of this scientific and most essential exercise process in the gym, where most individuals and even fitness trainers (so called certified) rush through the various exercises without any consideration to the understanding of the various body responses: reduced range of motion in a joint, misalignment, unnatural spinal movement, blood pressure, decrease in blood flow to the organs, high heart rate, lack of oxygen, muscle fatigue, energy depletion, hormone secretion, etc.

Understanding the functioning of the body during exercise ought to be of the utmost importance to you. At least it is of the utmost importance to me and my clients. Our body is made up of various systems such as musculoskeletal, endocrine, nervous, cardiovascular, respiratory, etc. When exercise starts (stress is introduced) all these systems respond simultaneously to achieve the exercise movement. Understanding how to prepare these systems for the exercise stress and how these systems respond to the exercise stress is essential in achieving optimal health, as is understanding their recovery process.  

Achieving optimal levels of health and fitness requires considerable time. It is therefore inadvisable to rush through the process of stressing the body just to achieve quick results. When stress becomes intolerable, the body enters the exhaustion phase and all the systems work harder to maintain homeostasis (normal physiological functions). This exhaustion leads to either acute or chronic distress. Examples of acute distress include fractures, sprains, and strains. Chronic distress is more subtle and includes stress fractures, emotional problems, and a variety of soft-tissue injuries.

Summary

Physical training is all about the principle of stimulus and response. Properly gauged and timed, training stimuli result in progressive improvement in functional capacity. Conversely, in the absence of appropriate stress, functional capacity deteriorates. You must also understand that performance capabilities change continuously throughout life. Application of too great a training stress and too frequent training will result in exhaustion of the physiological system. Resting is an indispensable part of training because adaptations occur during recovery.