Gains. Millions of people go to the gym to achieve gains in some aspect of fitness, whether it be strength, endurance, power, etc. Most people assume that if you go to the gym more often, you will achieve more gains. In theory, this sounds like a no brainer. Except in reality, this is not always the case.
Before we begin, let’s define a couple of terms: gains and adaptations. In science, the definition of “gains” means “to increase the amount or rate of something, typically weight or speed”. Along the same line, adaptations mean “a change or the process of change by which an organism or species becomes better suited to its environment.” When a person exercises, they are not actually making gains, they are adapting. The human body is adept at acclimating (adapting) to external stimuli, whether it be ambient temperature, pain, or even exercise. When you exercise, your body takes a myriad of measures to make sure it fuels your muscles as efficiently as possible, allowing for the best possible advantage. In essence, your body adapts to the workout. This is why one needs to change their exercise routine every so often.
What happens during post workout? As they say, “This is where the magic happens.” During your workout your muscles will accumulate micro tears and micro trauma, which manifests itself as “soreness”. Your body will use amino acids (the building blocks of protein) along with a plethora of hormones to repair the muscle. This repair to the muscle makes it stronger than previously, allowing for similar or even larger tasks to be taken on. While the muscle is being repaired, your body is also replenishing its fuel sources within the muscle in the form of glycogen (stored glucose). This process can take anywhere between 24 and 48 hours depending on the conditioning of the person in question.
So what does all of this mean? To put it simply; adaptations are made in the gym, gains are made in recovery. Rest days are essential if you want to make any sort of gains. Your body cannot handle short recovery times. Take at least one day between exercising. Your body will thank you.