Anabolism is the synthesis of new protein in the body, building new muscle mass. During this anabolic window, your body is much more likely to synthesize protein.
How Do You Open That Anabolic Window?
The window opens when you exercise, especially when you lift weight, specifically when you do muscle hypertrophy activity or resistance activities, you are breaking small muscle fibers. What your body does next is rebuilding that muscle, adding more mass, preventing more fiber breaks.
To exercise, your muscles use the glucose stored in them to do work. So, when you finish your routine, your muscles are “damaged” and need to recover. We will explain all this in more detail below.
The anabolic window theory is based on the anabolic response of your body.
Anabolism occurs when small molecules turn into larger complex molecules. These molecules form in new cells and tissues, including muscle. It is the opposite of catabolism, or when larger molecules break down.
After strength training, your body is in an anabolic state. This involves a variety of cellular processes that facilitate muscle repair and growth. These processes feed on protein and carbohydrates.
According to the theory of the anabolic state, this anabolic response is a limited time frame of only 30 minutes. It also states that eating protein and carbohydrates right away is essential for:
- increase protein synthesis
- reduce muscle protein breakdown
- muscle glycogen replacement
There is some truth in these statements. According to a 2018 Study from Trusted Source, Muscle Protein Breakdown (DPM) increases in response to strength training. Muscle protein synthesis (PMS) also increases, but to a greater extent. The balance between DPM and SPM determines muscle growth. This balance is called the net muscle protein balance (ENPM).
Post-workout nutrition can affect these processes. Protein intake limits MPD and supports PMS. Carbohydrate intake also inhibits DPM and helps glycogen resynthesis. Glycogen provides energy to muscles.
After exercising, it may seem logical to eat protein and carbohydrates right away to suppress MPD. This is also supposed to increase muscle mass by increasing ENPM. This is where theory oversimplifies science.
Changes in muscle size depend on myofibrillar proteins. To increase muscle mass, DPM suppression should target only these proteins.
However, DPM (breakdown of muscle proteins) affects many types of proteins. This includes muscle proteins that are quickly chipped or damaged.
The breakdown of these proteins may be essential for remodeling muscle. This suggests that trying to limit MPD through post-workout nutrition could actually hinder proper recovery.
In addition to nutrition, there are many factors that affect recovery and growth, including age, hormones, and training routine.
There is also no solid evidence to indicate that the anabolic window lasts only 30 minutes. It is unclear where the suggested time frame came from.
We do not know whether or not the Anabolic Window will exist, as there are many scientific studies done on the subject that contradict each other. What if it is true that after an intense exercise our muscles ask to feed because they need to recover.
Science and The Anabolic Window
The concept of a short time anabolic window is a widely held belief. Research shows that it is not as short or as simple as it sounds.
A small study from 2017 found that protein intake before and after training produces similar muscle adaptations.
This suggests that pre-workout protein might be sufficient and immediate post-workout intake is not much better. He also proposes that the “window of opportunity” for proteins is much wider.
An older study from 2007 had comparable results. Participants consumed buttermilk just before exercise or 1 hour after.
Both groups experienced similar changes in muscle protein synthesis. Additionally, a meta-analysis of 43 studies found no strong link between immediate protein intake and muscle growth or strength.
The role of immediate protein intake in muscle protein breakdown may also be exaggerated.
A 2010 study examined the post-workout anabolic response that occurs after protein intake. The researchers found that the response is due primarily to protein synthesis rather than protein breakdown.
This suggests that it may not be necessary to eat immediately afterward to reduce muscle breakdown.
The exception is if you exercised while fasting. According to an earlier study from 2003, fasting exercise significantly increases post-workout muscle breakdown. Therefore, if you do not eat before training, it is important that you eat immediately afterwards.
Finally, a 1997 study found that delaying carbohydrate intake for 2 hours after training did not affect muscle glycogen resynthesis. Glycogen levels remained the same 8 and 24 hours later, suggesting that subsequent carbohydrate intake may still be beneficial.
