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Effects of alcohol on diet and training

Something we find ourselves talking about repeatedly to clients is alcohol consumption. This is normally related to clients putting weight on or struggling to lose weight. The basic gist is that alcohol is high in calorie and seriously lacking any nutritional value to help you achieve any sort of body composition goals. However, there is more to alcohol than meets the eye, and the following info shouldn’t go un read by a lot of our clients. Alcohol Metabolism When you drink beer, wine, or spirits, the ethanol in those beverages is given priority by your body in metabolism. It stops pretty much everything else and goes to work in a four step process that looks like this: Ethanol → Acetaldehyde → Acetate → Acetyl-CoA Acetate and acetyl-CoA can be used for energy by the body but it’s costly. One gram of alcohol is said to contain 7 calories, but like protein, its conversion into energy is inefficient and 17 to 20% of its energy is lost. In other words, like protein it has a very high thermogenic effect. Also like protein, and contrary to popular belief, alcohol is not easily converted to fat. That process is too costly. But all that acetate and acetyl-CoA showing up in the cells does signal to the body that no sugar or fat needs to be burned. So rather than a fat storer, alcohol is more of a fat burning suppressor. So maybe alcohol isn’t a bad as you thought…..  or maybe there’s just more to it than you thought. Muscle, Body Fat and Performance To build muscle and burn fat you need to manage calories and hormones. Alcohol impacts both. When you drink you consume calories. And under certain conditions it can impact the hormones that help your body build muscle and stay lean. Alcohol also has its own effects as a cellular messenger and as such impacts brain chemistry and muscle cell signalling. And all this has an impact on building muscle, burning fat and performing. Here’s the part that’s going to blow your mind. You may be able to use alcohol and still be able to get great results. That is, if you know how to use it and what you’re using it for. If you’re going drink – and you probably are – the goal is to do it with minimal impact on your physique or your performance. Does Alcohol Halt Muscle Building? You’ve probably heard alcohol crushes muscle building. And in this area you are probably correct. Alcohol has several mechanisms that will negatively impact muscle protein synthesis and recovery from exercise. However, as long as you keep it moderate you may be safe. Alcohol has these effects on muscle metabolism: raises myostatin, decreases glycogen resynthesis, decreases post-exercise inflammation (yes, this is a bad thing), suppresses exercise induced mTOR (likely by reducing cellular phosphatidic acid) and it may impair insulin and IGF-1 signalling. If you’re not a biochemistry buff, all this equals BAD for muscle. However, there does seem to be some caveats. An excellent review by Matthew J. Barnes published in the June 2014 issue of Sports Medicine shows some very clear rules when it comes to alcohol and highlights several studies you’ll want to know about. In one study, Barnes gave subjects 1g/kg alcohol or a equal volume of a non-alcoholic beverage. These drinks were consumed 30 minutes after having them complete 300 eccentric reps for the quads (ouch!). So, basically there was a group drinking the hell out of some booze and another group getting their swerve on with a jug of Tropicana (the control group drank orange juice). Both groups were trashed 36 and 60 hours after the workout in terms of strength in isometric (holding), concentric (raising), eccentric (lowering) contractions. But the alcohol group’s muscles had a much worse hangover. They performed 22%, 12% and 15% percent worse in those three measures compared to the OJ group. To make this more tangible for you, and so you can understand how much booze was consumed, 1g/kg is 1g/2.2pounds. That equates to about 80g of alcohol for a 180-pound person. And since the average alcoholic drink (4-5oz wine, 12oz beer, 1.5oz spirits) has about 14g of alcohol in it, if my math is right, that’s about six alcoholic drinks. So the study results are about what you’d expect, right? But here’s the part that you’ll love if you like to drink. Barnes did a similar study where he pitted 1g/kg alcohol consumption against .5g/kg alcohol consumption. And that showed once again that the 1g/kg alcohol level torpedoed muscle recovery, but the .5g/kg alcohol consumption had no effect. So for that same 180-pound dude, six drinks crushed him. But three drinks and he stayed in the clear. That’s a pretty useful rule of thumb if you ask me. And this same threshold level of .5g/kg alcohol is backed up on other studies showing higher levels negatively impact rehydration metabolism. So all those hours spent trying to reinforce moderation rather than complete restriction now finally have science to back them up!!!!! How Does Drinking Affect Performance? There are some general guidelines as it pertains to recovery from athletic events. It may shock you to learn that athletes who drink post-competition don’t seem to be all that impacted. A study on this was done on a bunch of rugby players. In this study, these guys drank on average 20 standard drinks. That’s about 3g/kg or three times the amount we were talking about in the Barnes studies. In other words, these guys got trashed after their match. Guess what happened two days later when they showed up for training? They performed at top level like nothing ever happened! Based on this and a few other studies in the performance area, if your liver doesn’t explode you’ll probably be able to perform just fine after a few days. To be on the safe side though, I’d take those days off. How Does Beer and Wine Affect Fat Loss? When we get into alcohol and fat loss, things get a bit tricky. In this realm we have to look at calories, endocrine effects (which impact muscle too) and the context in which alcohol is consumed. Let’s review what we already know. The biochemistry of alcohol metabolism says that it has a very high thermic effect, just like protein. It’s also costly energetically for alcohol to be stored. When acetate and acetyl-coA build up, this shuts down burning of other fuels like carbs and fats. Studies support this. When carbs or fat are replaced calorie-for-calorie with alcohol, there’s no fat storing effect. Some of the research even hints there may be a weight loss effect in the same way that subbing protein in place of fat and carbs might have. Another thing we have to look at is how alcohol impacts food intake. This seems to be individualized with some suffering from a “disinhibition effect” and others not. By disinhibition I mean that people’s natural control mechanisms to regulate the amount of food they eat is reduced. So, just as people become uninhibited when they drink and say all types of crazy stuff they wouldn’t say sober, others can eat all kinds of food they may not eat when they’re sober. This impact on appetite may vary with the type of alcohol consumed too. There are a few rules here to know. Beer is bitter and bitter compounds release GLP-1, which is a hunger suppressing compound. Beer also seems to lower cortisol in the short run and in lower doses. Higher doses may have the reverse effect. This is important because we now know cortisol is involved in hunger and cravings, and switches off the motivation centres in the brain while amping up the reward centers. This may also be related to the hops in beer which, as an herb, has a sedating quality. Red wine contains histamine which raises cortisol. So we assume this would mean increased appetite. Spirits and white wine have neither the bitter compounds or the histamine content of beer and red wine, so it would be difficult to speculate the effects. A study out of the journal Pharmacology, Biochemistry & Behaviour by Dr. Anna Kokavec shows exactly what we’d predict. Beer lowers cortisol and has a short-term appetite suppressing effect. Red wine raises cortisol fairly quickly and stimulates the appetite faster too. White wine was similar to beer. Spirits were not looked at in this study. It does seem to be clear that any alcohol will raise cortisol eventually. The effects just seem to be time dependent in the case of beer, and impacted by amount as well. We now know cortisol has some impact on appetite, but it also plays a role in workout recovery. You don’t want cortisol high in either scenario. Alcohol also seems to impact brain chemistry which is known to impact hunger and cravings. It raises dopamine and lowers serotonin. Dopamine is associated with desire and reward. It raises adrenaline and also lowers melatonin. This can negatively impact sleep, which is highly correlated with increased hunger and cravings. A research report out of the journal Appetite gives us the following points related to alcohol intake taken before meals. All alcohol increases food intake but the strength of this effect depended on the drink consumed. The breakdown from this study, plus my extrapolation of a few others, goes like this: Beer & White Wine < Red Wine < Mixed Drinks Testosterone and Other Hormones And what about the reported effects alcohol has on testosterone, estrogen and other hormones. This seems to depend on the amount and context in which the alcohol is consumed . Again, the threshold level of .5g/kg comes up in the research. Alcohol intake at this level seems to have little impact on testosterone at all. Alcohol may impact you differently depending on what you do. Consuming alcohol after exhaustive endurance exercise definitely exaggerates the lowered testosterone levels typically seen in this type of activity. The study showing this used 1.5g/kg. That’s about eight or nine drinks for our theoretical 180 pound man. But when drinking occurs after weight training at levels of 1.09gkg (about five or six drinks), both free and total testosterone levels are actually elevated. By the way, most research on women seems to suggest alcohol may raise testosterone levels a bit. And if you understand female physiology, this is not a great thing, especially for their midsections. When it comes to testosterone, the rules seem to be: 1.  Keep alcohol consumption light (less than three drinks). 2.  If you’re going to drink more, do it after weight training. 3.  Alcohol after cardio is not a great idea. HGH and Estrogen Alcohol also lowers HGH, but it really doesn’t seem to impact estrogen the way we once thought. A three week intervention on men and post-menopausal women showed once again that the .5g/kg alcohol level (about 30-40g alcohol in this study) had no impact on circulating estrogen. And two other studies I looked at using 1.5g/kg alcohol and 1.75g of alcohol didn’t seem to impact estrogen either. Surprised? So was I. It seems that if anyone is going to be impacted by increased estrogen as it relates to alcohol it’s women and not men. Obviously an entire book could be written on this subject. The research is confusing and contradictory at times, and more studies need to be done. But we can make some general points.

  1. When including alcohol at meals, avoid carbs and fat. Stick to protein and veggies. You’ll ramp up the thermic effect of the meal and avoid storing those fat and carb cals.

  2. When choosing your alcohol, go with beer and white wine. They seem to have a better impact on appetite.

  3. Avoid mixed drinks. The alcohol plus sugar means you’re likely to store that sugar plus you’ll drink more.

  4. Alcohol intake under .5g/kg may be the threshold to keep you safe from any negative effects related to muscle wasting, fat gain, endocrine dysfunction and performance issues. (Yes, both types of performance issues!)

  5. Alcohol after cardio may not be a great idea.

  6. •Alcohol after weight training may be the best time to drink, but keep your intake under 1g/kg.

  7. As long as you’re doing most other things right and not drinking yourself into a stupor nightly, your worries of man-boobs and shrivelled testicles are likely overblown.

Final point reiterated: Alcohol is a non-nutritive calorie source. It’ll drain your levels of B-vitamins, zinc, magnesium and others. This can put you at risk for what’s known as long-latency diseases or issues. This is when the metabolism suffers slowly over time due to poor nutrition. So, any time you drink, make sure you supplement with a good quality multiple vitamin and mineral supplement.

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