Training is a very broad term, so let’s split it into the two main types of activity we can do as humans – Prolonged, low-intensity activities (cardio) & short-burst, power output activities like weight lifting or bodyweight training.

During cardio activities of moderate-intensity (swimming, jogging, skipping, etc.), we mainly use muscle and liver glycogen, which are simply, the stored form of energy from carbohydrates.

On top of that, we engage the slow-twitch muscle fibers, which are the muscle components that allow us to go through prolonged physical activity.

With this type of activity, there really isn’t significant muscle damage, so adaptations occur quickly and you can do cardio activities regularly, or even every day.

On the other hand, however, vigorous, high-intensity training activities like weight lifting and calisthenics, are way more strenuous.

These lead to muscle damage and overall, more fatigue on the muscular and nervous systems.

By nature, high intensity is more strenuous for the body and thus, requires greater recovery periods to rejuvenate the muscle fibers, nervous system, and energy compounds used.

What Adaptations Occur After Training?

After you are done with your training session, recovery processes start taking place, which in turn lead to different end results (adaptations).

In the case of cardio training, the main adaptations occur in the cardiovascular & respiratory systems, allowing your body to become more efficient and have increased endurance.

On the other hand, intense training leads to adaptations on a muscular & nervous system level, leading to increased strength, power output, explosiveness, and visual development

Here’s something interesting…

Supercompensation

When it comes to weight training and post-workout recovery, there is a state reached after a certain point, called “super-compensation”.

To simplify this sports term, super-compensation basically means that a training load, paired with proper recovery, will not only lead to getting back to base level performance but ALSO an increased capacity and a higher level of performance, than the previous one.

Essentially, the state of super-compensation is reached when the exercised muscle group or function, has a higher capacity and output than it had prior to the training session.

How Long Does Recovery Take?

The main portion of the recovery processes and the state of super-compensation take place during and at about the 72nd-96th hour after a workout

This means that roughly 4 days after an intense training session, you are likely to already have increased levels of strength and other functions.

As mentioned, for low-intensity cardio workouts, this can be 24-48 hours!

At its very essence, this is the body’s way of preparing for a greater load in the future.

In being so, this means that super-compensation is not really permanent – If you don’t create a new stimulus during that state, your performance will likely get back to baseline or lower, after some time.