What is the Anabolic Window? Probably a Myth.

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The ‘anabolic window’ (also called the post-exercise window of opportunity) is said to be a 30 – 60 min period of time after you workout during which you need to ingest the right nutrients (particularly protein and carbohydrates) if you want to maximize your muscle growth.

Supposedly, if you don’t eat a meal rich in protein and carbs (or get a supplement into you) during this window of opportunity you won’t get as much muscle growth (anabolism) as possible, or perhaps none at all. Now, some bullet points:

  • The anabolic window is probably a myth. Recent research has shown that such a narrow window of time after working out is unlikely to exist.
  • The most important nutritional factor is probably the overall amount of protein you consume in your diet (long-term, not day-to-day).
  • If you’re unsure, then try to consume a well-balanced meal or high-quality supplement within 3-4 hours of working out (either before or after).

Confused? Especially about that last point? That’s ok, come with us as we unpack the whole thing, try to cut through the BS, and land on some practical recommendations for you.

Anabolic window origin story

The idea of an ‘anabolic window’ came about after a number of scientific studies suggested that ingesting protein, either by itself or in combination with other nutrients (usually carbohydrates), immediately after resistance training could be necessary for optimum muscle growth.

This found its way onto internet forums for bodybuilding and exercise, and then into gyms the world over.

Then it somehow morphed into the idea that you must ingest protein immediately after working out, and quickly became a commonly repeated piece of ‘broscience’. This, in turn, led to ridiculous behaviors, mostly from young male bodybuilders, like running out of the gym immediately following a workout, jumping in the car and speeding home to scoff a big bowl of chicken and rice, or shoveling down cans of tuna right there in the gym’s locker room.

So what’s the big deal?

The problem arose when other researchers studied the idea more closely and couldn’t find consistent evidence to support the existence of the anabolic window. Now, you may be wondering ‘what did they find, all those researchers?’ Great question! Unfortunately, it’s a real mixed bag. But let’s have a quick look:

  1. Some researchers found that people gained more muscle when a protein + carbohydrate supplement was taken immediately before and after working out, than when the same supplement was taken early in the morning and late in the evening (i.e., long before and long after working out). On the flip side, other researchers found that people gained more muscle when a protein + carbohydrate supplement wasn’t taken immediately before and after their workout, but was instead taken in the early morning and late evening.
  1. A couple of studies found that whether people ate 1, 2 or 3 hours after working out didn’t make any difference to the extent of their muscle’s ability to grow larger, while another piece of research showed that muscles take in and use protein as much as 24 hours after working out.
  1. Another study found that people who took a protein supplement immediately before and after resistance exercise gained more muscle in some muscles but not others, whereas a similar study found that people who didn’t take a protein supplement immediately before and after working out gained just as much muscle as people who did take a protein supplement.
  1. A study that examined all the other studies together found that it probably doesn’t matter whether you eat a meal or take a supplement before or after working out, and that the most important thing is that your long-term diet contains enough protein to support muscle growth.
  1. Most recently, a very well-designed piece of research found that people gained just as much muscle when they ingested a protein supplement immediately before their workout as people who ingested the same supplement immediately after working out.

*Please note that this is a very brief overview of some relevant pieces of research, and not a comprehensive review of the full body of literature.

Lots of findings that contradict other findings, and not a lot of certainty around when you should or shouldn’t consume your protein and carbs. But the fact that scientific studies have never consistently supported the idea of the anabolic window means that it is almost certainly a myth, and you shouldn’t be worried about it (if you ever were).

What to do, what to do?

So what can we confidently say from a practical standpoint? What should you eat, and when should you eat it? More good questions. Based on the scientific literature as a whole, here are some practical recommendations.

What you should do:

  • If you are trying to see the most muscle gains from your workouts, you’ll want to make sure you’re ingesting enough protein in your overall diet. The evidence we currently have suggests that if you workout regularly and are trying to increase your lean muscle mass, you need to consume no less than about 0.72g of high-quality protein per pound of body weight per day to make sure your muscles have what they need to grow.
    • So, if you weigh 180lbs then you need to be consuming upwards of 126g of protein a day.
    • A medium-sized egg contains around 13g of protein; chicken breast contains approximately 32g of protein per 100g of breast; and an average-sized beef steak contains about 60g of protein.
    • If you eat these kinds of protein-rich foods daily with plenty of fruit and vegetables included (e.g., by adhering to something like the Atkins or keto diet), over the long-term you should be getting enough protein to support muscle growth.
  • If you are concerned about the timing of your meals relative to working out, the rule of thumb is pretty simple. Eat a balanced meal (containing protein, carbohydrates, and fats) within 3-4 hours either before or after your workouts, and you’ll be absolutely fine. If you have a particularly large meal, you can extend that time frame out to about 5-6 hours.

What you shouldn’t do:

  • You shouldn’t consistently consume less than the recommended amount of protein (0.72g/lb/day) and you certainly shouldn’t neglect your protein intake altogether. If you do, you will not be giving your muscles what they need to grow most effectively. If you’re struggling to consume as much protein as you need in the foods you eat, go ahead and supplement your diet with a good quality whey protein powder like this one or this one.
  • Day-to-day, don’t stress about when you ate your last meal or when you’re going to be able to eat your next. Simply make sure you’re eating plenty of protein in your long-term diet, and make sure you are doing good quality workouts and WORKING HARD! All the protein in the world can’t replace hard work.

Wrap it up!

So, to summarize: The anabolic window probably isn’t a thing; eat plenty of protein in your diet; if you are concerned about nutrient timing, eat within 3-4 hours either before or after your workout; and WORK HARD.

Thanks for reading the article! Leave any thoughts or comments you have in the comments section below.

As always, all the best with your home workouts. Remember: when it comes to our health and fitness, we can make excuses or we can make the effort, but we can’t make both.

THFF (The Home Fit Freak).


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