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A question I get asked so often is "should I eat before my workout complete it fasted?" The honest truth is that there is no one-size-fits-all approach when it comes to pre-workout nutrition. We are all different with different needs. Whether you workout fasted or fed really comes down to personal preference and what works best for the individual. To find the strategy that works best for you it's important to experiment and ideally do this under professional guidance. I know for myself, there are some days I workout fasted and other days I workout fed purely due to my day's schedule. Sometimes I feel a difference and sometimes I don't. So put aside an individual's personal preference, what's the actual scientific background to this controversial topic? The following is a very condensed summary on this topic.

Firstly, what is a fed workout and what is a fasted workout? Fed workout is when you have eaten before a workout...obviously. You can be in a fed state for up to 4 to 6 hours on average. A fasted state is when your body has not eaten for several hours (usually 8 to 12 hours). However, it can be shorter for some people depending on how quickly your body can digest meals. One of the common debates regarding this topic has been "if you workout in a fasted state you will lose fat as your body is using its own energy stores and in turn you will burn fat"...right? Ahhh, no not quite. You see, this short term fat burning process means absolutely nothing for fat loss if your long term balance over days and weeks is not right. So let's break it down. If the amount of fat you burn stays the same as the amount of fat you store, body fat remains the same. If you burn more fat than you store, you'll lose body fat. So this fat balance equation is really dictated by your total calorie intake. So sure, fasted training is going to burn more fat than if you were fed, but if at the end of the week you have consumed more calories than your body required, no amount of fasted training is going to help.

Will a fasted state negatively affect performance? Probably not, and again it comes down to each individual and how their body reacts in certain states. In terms of study results, many studies have shown no negative impact even when it came to resistance training, as your body uses your muscles glycogen to fuel the workout. Even after an overnight fast, muscle glycogen stores aren't depleted. And studies have also shown that even when muscle glycogen stores were low, resistance exercise performance is maintained.

Will you lose muscle if you train fasted? No. Your body is constantly building and breaking down muscle in a 24 hour period. Whether you build or breakdown muscle depends on the net protein balance long term. As long as you're consuming some protein around the workout period and an adequate amount of protein by the end of the day, there is no need to worry about muscle loss when training fasted.

So take home message...

* Fasted training is not more superior than fed training. If your goal is to lose fat, don't worry about whether you should workout fasted or fed, be more concerned with your total calorie intake and the type and amount of exercise you're doing.

* Performance shouldn't be affected in a fasting state but every body is different and if you find it is affecting your performance, then consume a small high protein snack about 30 minutes prior to your workout.

* If you are training fasted, it is a good idea to consume a high protein snack (25 to 30g protein...protein shake is a great option), within 1 hour of finishing your workout.

* No, you won't lose muscle if you train fasted.

So, do what feels right for you. Don't train fasted or fed because you think it will achieve your weight loss goal or help you perform better or worse, or help build muscle as opposed to lose muscle. It just comes down to what works best for you, as fasted or fed won't be what makes or breaks your fitness goals.

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