The theory of overtraining is one the most hotly contested topics within the fitness industry at the present moment. There are some individuals who believe overtraining to be a myth, and bracket this as a lax attitude for training and achieving fitness goals, coined by fitness academics solely to serve as a talking point at conferences.
In contrast, there are others who contest this and state that overtraining is a very real issue, which needs recognizing and addressing in order to facilitate fitness goals.
The reality is that overtraining is a very real problem, often noticed too late. Symptoms for overtraining include:
Training can be both good and bad for the immune system. Light/medium intensity training with sufficient rest periods can improve the body’s immunity, however there is a fine tipping point. If you train intensely – typically identifiable by prolonged bouts of exercise inducing increased heart rate – without taking recovery days, you will then become susceptible to weakened immune health and illness. Simply put: if you don’t rest, your body will make you rest!
As you train, the muscle itself is actually being damaged and broken down, it is only once the recovery process has taken affect that you’ll begin to see results. Without this recovery phase the muscle will remain constantly inflamed and functionally compromised, this can cause severe muscle soreness, also known as DOMS (delayed onset of muscle soreness), only rest and recovery can aid this ill affect on the body.
Similar to the point above: in order for muscle to develop it must first heal from the exercise induced breakdown. Furthermore, lack of rest is also detrimental to the central nervous system (CNS): the system of the body responsible for generating muscle contractions. Fatiguing this system will worsen the quality of muscle contraction and ultimately lead to lifting less weight and even injury, as muscle groups become compromised and form worsens. Allowing your CNS sufficient time to recover will enable muscle to perform optimally and maximal weight to be lifted.
You stop losing fat
This may seem like a strange side effect to training, given that we live in society that usually deems more to mean better, however this effect is very real. When you overtrain your hormones begin to change; cortisol increases and testosterone is depleted which leads to metabolic issues and muscle waste, ultimately causing undesired results if the goal is to reduce fat and increase lean muscle.
Furthermore, the systemic fatigue from all this compounded fatigue makes keeping your daily energy expenditure high, a tougher and seemingly more arduous process. This impact will ultimately reduce your calorie expenditure day to day: a large part of the fat loss equation.