The issue of workout nutrition, including how much to have, what to have and when to have it, seems to be cause for extended and heated debate in the fitness industry.
Recently a couple of things have got me thinking about the timing of my pre and post workout nutrition. The first was a series of articles that cropped up on various blogs and online magazines. The second was my cutting cycle.
I’ve been doing some further reading and thought I would share some of the things I learned along the way.
My current workout nutrition timing
For a lot of people pre workout nutrition doesn’t seem to be of great importance, but I have always had some sort of pre workout snack. This is most likely to be because I workout in the evenings and I’m usually starving by the time I get home from work. There’s nothing more unpleasant than working out on an empty stomach.
Post workout, when not cutting, I was having a small follow-up snack. I was making sure that I had this within 20 minutes of leaving the gym, paranoid that if I didn’t do that I would be missing the vital “window of opportunity” to get the benefits of my post workout snack. During my cutting cycle in January I dropped my post workout snack entirely. Interestingly I didn’t see any significant drop-off in my performance in the gym and I got the impression that I was continuing to gain some muscle.
Of course, I tend to workout in the evening or late afternoon, so the reality is that I usually have my dinner within an hour of leaving the gym as well.
Exploding some myths and the importance of pre workout nutrition
As an excellent starting point for anyone who wants to learn about pre and post workout nutrition I recommend reading and article by Dave Barr on Testosterone Nation which summarises ten myths surrounding workout nutrition and provides references to the supporting research that explodes these myths, or at least makes you think twice about them.
The key points for me on reading this article were:
- pre workout meals enhance muscle blood flow and nutrient delivery during exercise;
- pre workout meals, nocturnal feeding and multiple post workout drinks are more beneficial than a single post workout drink;
- the “post workout window” lasts at least 24 hours; and
- consuming a protein shake immediately after training hinders optimal results (better to wait up to an hour to have your shake).
Above all it seems that pre workout nutrition is as important, if not more important, than post workout nutrition.
Do we need to down a shake straight after dropping the bar?
Timing of post workout nutrition
The last point that I’ve pulled out from Barr’s article suggests that consuming a protein shake immediately after training hinders optimal results (better to wait up to an hour to have your shake). However, Barr is comparing the results from two separate studies to conclude that protein synthesis rates are 30% lower if the protein shake is ingested immediately after training. My concern is that the content of the post workout nutrition differs in these two studies so they can’t be compared directly like this.
I mentioned above the study by Tipton et al. (2003) which concluded that the “window of opportunity” lasts for at least 24 hours. This was based on comparison of the response between 3 hours and 24 hours and shows that there is no difference between these two periods. This can be tagged onto the study by Blake et al. (2000) which shows very little difference in protein synthesis rates between 1 hour and 3 hours. So it seems that you’ll get as much benefit from meals you consume an hour after exercising as you will 24 hours after exercising.
However, a separate study by Levenhagen et al (2001) compared leg glucose uptake, whole body glucose utilisation and protein synthesis in athletes taking in an oral supplement consisting of 10g protein, 8g carbohydrate and 3g fat either immediately or 3 hours after a 60 minute session of moderate-intensity exercise. The study showed that immediate ingestion of the supplement gave higher levels of glucose uptake and protein synthesis than leaving this for 3 hours.
Authors of articles who support the argument that the window of opportunity is very large seem to ignore the Levenhagen study, while those who support the immediate nutrition argument seem to only make passing comment to the Tipton and Blake studies.
Summary
There are plenty of things to learn from this, but I’ve picked out some key points below.
- Pre workout nutrition is vital to good performance and improvement.
- Post workout nutrition has an enormous “window of opportunity” and you’ll still be getting glucose uptake and protein synthesis benefits from your meals for at least 24 hours after you stop exercising.
- Despite my previous point, getting some nutrition in immediately after your workout looks like it will give you some maximal benefits.
So it seems I might have been getting a slight loss of benefit by dropping my immediate post workout snack, but I still get benefits from my dinner less than an hour later.
I’d love to hear from you if you’ve seen other research that disagrees with this information – workout nutrition seems to be a minefield of contradictory studies!
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