I’m just about finished the next update of How Much Protein, and I think the new editions to the book will really help people understand my views on protein.
However, on piece of research is too interesting for me not to share with you today…
Most research conducted on the acute muscle building affects of post-workout protein have two interesting thing in common – they measure protein synthesis as a marker of muscle growth and the subjects in the studies are almost always fasted at the beginning of the study.
Typically, the people in a study that is examining the anabolic affects of post-workout protein show up to the lab after an overnight fast, then will fast for an additional hour or two while the study is being set up. Then they workout, usually doing a a grueling leg workout of 8 sets of 8-10 reps using 80% of their 1 rep max on leg press. After the workout (which takes anywhere from 20-45 minutes) they are then given their post-workout drink either immediately or within an hour, and then they sit quietly while the researcher take measurements for 3-4 hours.
It could be anywhere between 12 to 16 hours of fasting before they are given the amino acids / protein.
This type of research consistently shows that protein synthesis after a workout is higher with the addition of post-workout protein then without it, at least for the 2-3 hours that they typically measure.
This is largely where we get the idea of post workout protein having muscle building benefits.
However, one group of researchers were curious if the pre-workout fasting was a confounder in these studies – If the large spike in protein synthesis found with post-workout protein was also a bit of an artifact of the fact that the subjects have been fasting.
So they switched the design.
They had a group of guys eat a standard dinner, then go to sleep. When they woke up they had a standardized breakfast containing about 500 calories and 30-50 grams of protein (depending on the subject). Then they waited for about one and a half hours then they exercised 1 leg with 8 sets of 10 reps of both leg extensions and leg curls at 70% of their 1 rep max, with 2 minutes rest inbetween each set. The other leg did not exercise at all.
Once the subjects finished their workout they had their protein synthesis levels measured in both legs, then they fasted for 6 hours and had their protein synthesis levels measured again.
Surprisingly, after six hours of fasting the non-exercised leg had levels of protein synthesis that would be expected after a large protein meal and the exercised leg had a rate of mixed muscle protein synthesis that was 20% higher then the non-exercised leg – reaching the same levels that are found in studies where people are fed protein after their workouts, showing that resistance exercises changes the way your body uses protein, directing it more towards muscle metabolism, and that this occurs when food is followed by a workout to a similar extent as when workout is followed by food. [Witard OC, 2009].
This is pretty good evidence to support the idea that it’s not your protein intake that makes your workouts ‘work’ to build muscle, but your workouts that make your protein intake ‘work’ – directing your body to use the protein you consume to repair and rebuild your muscles that were stimulated by weight training – Which is why you simply can’t eat more protein and get bigger muscles, you do have to direct that growth.
With this in mind I’d like you to try an experiment – just to see how engrained the idea of post-workout nutrition truly is in our brains.
I want you to Eat Train Fast (please don’t steal this, I may use it).
- Eat a meal – not a quick protein drink but you know… actual food. Protein, Carbs and fat. Make sure it contains some protein… let’s say at least 30 grams, but go as high as you want.
- Then wait an hour or two.
- Then do a weight training workout.
- Then fast for at least 6 hours.
The experiment isn’t to see if you get better muscle growth (it’s one workout after all) but rather to see how attached you are to the ‘need’ for post-workout protein. To see if you can go 6 hours without a pang of protein guilt – thinking that you really should eat something to feed your muscles, or to help your muscles grow.
And to be clear, I’m not saying there may not be a small additional benefit to also having a post workout meal, or that pre-workout meals are somehow superior to post-workout, but this line of research shows that as long as you eat at some point before or after your workout you’ll see a benefit from that workout, or maybe more accurately, the workout will make sure you see a benefit from your protein intake.
Really this is a study on the power of marketing and advertising… seeing just how attached we all are to the idea of post-workout protein to the point where missing even one meal is difficult.
So it will be interesting to see if you can do this approach, or if the need for post-workout protein overtakes you.
Try it out,
PS- No cheating and simply going to bed after your workout 😉