Nutrient timing is a popular nutritional strategy that, in this case specifically, involves taking a combination of nutrients—primarily, EAAs, BCAAs protein and carbs -in and around the time when you train.
However, it’s the “anabolic window” which is referred to specifically as the period (usually given as 30 minutes) immediately following a workout that’s taken on a higher level of focus – and it has been become ingrained in the bodybuilding/sports nutrition culture for decades. The strategy being simple: You need to consume protein and carbs during this “window” to take advantage of increased uptake of protein and carbs by the muscles brought about by training or risk losing potential gains.
But how much of this “window” is based on real science and how much is just really good-sounding bro science and theory?
For starters, you’ll probably hear the window described in minutes – which is actually more good-sounding theory. Modern research suggests that your body’s post-workout state lasts anywhere from four to six hours. So while athletes in the 1990s were often under the impression that you had to ingest your protein and creatine immediately after you put down the weight of your last set, it’s actually more important to eat a protein-rich meal within a couple of hours of your workout, both before and after. In fact, it’s your total daily protein that’s key when it comes to getting results – not the time it’s consumed. That doesn’t mean you should stop mixing up a quick shake after training. If consuming protein after your workout offers a convenient and consistent time to consume a portion of your daily intake while delivering a measure of rehydration, then continue to do so.
Where the “window” is based on real science however, is when it comes to creatine. While it seems intuitive to take creatine pre-workout, it’s actually post-workout that seems to be the consensus best time to take it for best results. In fact, a 2013 study found that taking creatine monohydrate lead to twice the lean muscle in those using it immediately after training compared to those using creatine pre-training. The advantages didn’t just apply to muscle gains – that same group of also lost more fat than the pre-workout group even though everyone was doing the same workout. A more recent meta analysis confirmed creatine supplementation immediately after resistance training was superior for increasing muscle mass compared to creatine supplementation immediately before resistance. While the meta-analysis did not provide a firm rationale for why creatine works better when taken post-workout, there are a number of theories why ranging from an increase in GLUT4 translocation and expression; to the post-workout muscle pump being able to more effectively deliver nutrients to the muscles.
If you’re curious – GLUT4 is an insulin-regulated glucose transporter that is responsible for insulin-regulated glucose uptake into fat and muscle cells. Increased GLUT4 activity occurs during muscle contractions and increases nutrients transport to the muscles. The GLUT4 stays active for some time at the conclusion of the workout – making an opportunity to consume some creatine and simple carbs. Scientists also hypothesize that creatine also improves the efficiency of GLUT4,, to there certainly strong synergies between creatine and the body’s state after training.
So while the days of lugging your tub of protein to the gym in your gym bag like you’re going on a picnic so you can squeeze in a shake during your anabolic window are certainly over, there’s definitely a strong case to consume a serving of creatine with some carbohydrates shortly after training.