Friday, July 1, 2011

What should I eat after training?

This is one of the questions I am most frequently asked and often the answer is one of the most difficult for people to understand. It's NOT difficult to understand because it's complicated, it's NOT difficult to understand because it's hard to explain, it's difficult to understand because there is so much misinformation available regarding this topic. The post workout nutrition puzzle has become so confusing that most people give up trying to solve it. It doesn't have to be complicated and it is something that everyone can take control of. To help everyone understand this better I am going to pull the post workout nutrition puzzle to pieces and put it back together in an easy way to follow (skip to the summary at the end if you just want the guidelines).



It is important to realise that most of the information available regarding post workout nutrition originates from old body building folklore. Most of this is based on limited and outdated research and spread from person to person in the gym and online. As expected, when information is passed from one person to another, it changes and changes, until it is unrecognisable. I have heard some of the most ridiculous post workout nutrition ideas and at stages of my training I followed them not knowing any better. After all, if the bigger, stronger and fitter person tells you something about training generally you listen, right? I wish I hadn't!

There are two main physiological consequences of exercise that post workout nutrition can influence. These include (1) minor physical damage to muscle and (2) depletion of muscle glycogen. Both strength and endurance physical activities bring about both of these physiological affects. The degree to which they occur is variable depending on a number of different factors including type, intensity, volume and familiarity of the exercise performed. Before we dig any deeper I will discuss these two consequences of training in a bit more detail.

  • When we train we cause minor physical damage to muscle. This might sound like a bad thing but in fact this is how our muscles adapt to training. As the muscles recover from the damage caused by training they are remodeled and become better adapted for next time. This adaption results in a more efficient muscle.
  • When we train we deplete muscle glycogen stores. Muscle glycogen is a readily available, locally stored energy source. There is a limited amount of muscle glycogen that can be stored by muscle and eventually these stores will deplete if they are not replenished.
Two important post workout nutrition goals can be established; (1) promote recovery from muscle damage to achieve optimal repair and adaptation and (2) promote replenishment of depleted muscle glycogen stores to achieve optimal muscle performance. So... how is this achieved?

Muscle Recovery
Recovering from muscle damage following training is achieved with protein intake. Dietary protein provides the necessary building blocks required to repair all body tissues. Without adequate protein intake muscle recovery is delayed which can lead to prolonged muscle soreness, inhibited adaptation (reduced strength, power, size and endurance gains depending on the type of training stimulus), reduced training and sport performance, an increased risk of  muscle injury and compromised immunity which may lead to illness. Three questions need to be answered regarding post workout protein intake; (1) how soon after training should protein be consumed,  (2) how much protein is required and (3) what type of protein is preferred?

The confusion surrounding post workout protein timing is one of the most debated nutrition topics amongst body builders and athletes. Often you will hear about a 'window of opportunity' following training described as being a magical time frame in which you must consume protein in order for your body to maximise training results. This time frame, depending on who you listen to, ranges from 30min through to 24 hours. The simple answer is that no one knows if a window of opportunity even exists. The only thing we know for certain is that if you consistently achieve your daily protein requirements you will maximise your ability to recover from training. Therefore consuming protein regularly during the day and eventually reaching your recommended daily protein requirements is the best way to optimse muscle recovery.

Consistent with healthy eating guidelines, regular protein intake during the day (eating every 2-3 hours while awake and therefore within 3 hours following training) is the best way to achieve your daily protein intake. Protein requirements are influenced by type, frequency, duration and intensity of training ( a range of recommendations for protein intake are summarised at the end of this article). 10-30g of protein is typically recommended as an appropriate serving size post workout (and at every meal) however rushing to the protein shake immediately following training appears to be unnecessary since recovery relies on achieving total daily requirements not just on post training intake.

Despite what a lot of sport supplement companies would have us believe, it appears that the type of protein is not that big of an issue either. All types of protein help aid recovery, however animal /dairy sources are more complete than plant sources. Recovery will benefit from the combination of all protein sources consumed during the day not just those consumed immediately follows training. Liquid protein sources and supplements are digested faster, convenient and easy to consume and transport however a protein drink or supplement is not a compulsory requirement of every post workout meal. Easy and convenient protein options are recommended post workout and often the type of protein consumed comes down to palatability and accessibility - not everyone feels like eating something solid or preparing a meal immediately after training. The type of protein source post workout can be different every time  however routine often makes things easier.

Muscle Glycogen Replenishment
Replenishing muscle glycogen stores following training is achieved with carbohydrate intake. Dietary carbohydrate provides the energy that fuels muscle and without adequate replenishment training and performance will be suboptimal. The same three questions need to be addressed; (1) how soon after training should carbohydrate be consumed, (2) how much carbohydrate is required and (3) what type of carbohydrate is best?

Evidence suggests that with adequate daily carbohydrate intake muscle glycogen can easily be replenished within 24 hours regardless of whether or not carbohydrate is consumed immediately following training. Similarly to protein intake, the timing or the type of carbohydrate appears not to be the major issue. Consistent with healthy eating guidelines, regular intake (eating every 2-3 hours while awake and therefore within 3 hours following training) of low GI carbohydrates is recommended for acheiving muscle glycogen replenishment over a 24 hour period. Daily carbohydrate requirements differ for each individual depending on weight control goals so adjustments need to be made for weight loss, gain or maintenance,

24 hour replenishment is appropriate for most people but for those that train or compete twice or more  per day a more rapid muscle glycogen replenishment is required. Consuming 1g of moderate to high GI carbohydrate per kg of body weight immediately following training has been shown to achieve a more rapid glycogen replenishment. Low GI carbohydrates are recommended as the preferred source of daily carbohydrate intake however it makes sense to include moderate to high GI sources immediately following training when rapid muscle glycogen replenishment is required.

In summary, it appears that the big focus on post workout nutrition needs to be redirected to total daily diet. The meal or snack that immediately follows training has been for a long time considered the most important meal of the day but we now know this is not the case. If the post workout meal is great, but the rest of the daily intake is inadequate what's the point? When you think about this it makes perfect sense - how would one meal out of the whole day make that much of a difference? If we are serious about our training or performance we need to think of every meal as pre and  post workout and consider how it will impact on our training results.

I have outlined some easy to follow guidelines below:
  • Eat regular meals every 2-3 hours (including within 3 hours of training) that include:
    • 10-30g of protein
    • preferably low GI sources of carbohydrate if not training again for 24 hours or longer
  • Training increases protein requirements so adjust intake accordingly
    • 1g per kg of body weight per day for general regular exercise
    • 1.2-1.6g per kg of body weight per day for endurance and strength training
    • 1.6-2.0g per kg of body weight per day for heavy endurance training or new strength training programs
  • Training increases carbohydrate requirements so adjust intake according to weight control goals
    • If you are aiming to lose weight reduce (but don't eliminate) carbohydrate intake so a steady weight loss is noticeable
    • If you are aiming to maintain weight increase or decrease carbohydrate intake so maintenance is achieved 
    • If you are aiming to gain weight increase carbohydrate intake so a steady weight gain is noticeable
  • If training again within 24 hours include 1g of moderate to high GI carbohydrate per kg of body weight as soon as possible following training
  • Focus on diet as a whole - every meal is important for recovery and performance

5 comments:

  1. Good article - thanks for the tips.

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  2. This is great stuff Dave, it's nice to read some advice that doesn't have some form of marketing hype/slant towards a certain product. It is understandable that in this increasingly superficial world, a lot of people are looking for that silver bullet to get that "edge" towards their body goals. Thus, the supplement market is born and all the innuendo that comes with it.

    All the while, people forget that it really is as simple as getting your diet right - just like most of us already know. Therein lies the problem, it is a simple premise, but difficult to maintain. It's little reminders like this article, complete with its sound logic and unbiased, educated opinion that put people like me (searchers for that silver bullet!!) back on the path to accelerated gains. There are no shortcuts!

    Great article Dave, keep them coming!

    PS. I promise I'll be back to Drive eventually, once I get out of this cycle of poverty that is student-hood.

    Corey P.

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  3. Very helpful. Thank you.

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  4. Great article Dave. A very interesting and informative read. Em

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  5. Great article!! Just the evidence-based facts... exactly what people need :-)

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