Carb cycling can be a very tricky thing but something that I feel is super prevalent and that needs to be talked about in detail so that you can see why you would do this, how it can be effective for your life and your training, and also some of those that might not want to do this. I will share some client experiences along the way as well.
First, what is carb cycling?
Carb cycling is essentially exactly what it states. You cycle carbs through high and low days. If you are tracking macros (carbs, fat, protein) then you can have some days of higher fat, lower carb and then some days of lower fat, higher carb. Let's get into the specifics of why you would want to do this and when it's appropriate and if it works.
Some of the reasons that you might carb cycle are:
- Fat loss
- Marathon/Ironman Training (different volumes on different days)
- Figuring out how your body best responds
- Restore hormone levels to normal amounts
All of these are valid reasons, however I would like to address one thing. If you are someone that is eating 1800 calories, and some days you are doing this low carb, high fat and then the other days with the exact same calories, you are eating high carb, low fat then the data in all clinical trails shows that this is not going to do anything for you. At the end of the day, it's calories in vs calories out. Before I go into all of this, I do want to say this. There are many things that are shown in clinical trials that maybe you have tried for yourself and seen success. If that is the case, then you know personally that it worked for you and you should honor that. Science is only as good as the study and those studied, and if you weren't in the study then you need to do what's best for you. I don't want this to come across as me telling you that what you are doing that has worked for you is like crap or something, because that's not true.
Bio-individuality is a very real thing, and there are people and families and cultures that process carbs better or don't process carbs well at all, and that needs to be taken into consideration. If you want to find what diet works best for you and your bio-individuality then in all honesty, the only thing that you can do is try all of them. Trial and error is truly the only thing that works in the end.
There is a wide spread thought that if you are having trouble losing weight, add in a refeed day. A refeed day is essentially a carb cycle where you are eating lower calories for most of the week and then one day per week, you jack up your carbs (most of the time you keep fat and protein moderate) and this is supposed to restore the hormone levels that affect your hunger and metabolism (specifically leptin and ghrelin). The refeed day however doesn't hold up in the tests of clinical trial. The hormone changes are not statistically significant, and the body fat changes are still only the same as someone who took the same calorie amount of the refeed day + lower days and averaged them out to a middle ground across the entire week.
At the end of the day, as many times as we want to beat around the bus in a million different ways, weight loss is simply energy expenditure. In vs out.
When you eliminate carbs from your diet, you are also eliminating something that comes along with carbs-WATER! So therefore, if you have a day that you do a low carb day then you are probably experiencing something that feels like weight loss when in actuality, it's water loss. When studies are put head to head with high carb days and low carb days but the same amount of protein and matched up fats to create the same caloric intake, there is NO difference in fat loss. The important thing that we want is fat loss. We don't really want water loss (it's nice to see on the scale but it's only transient) and we DEFINITELY don't want to see muscle loss.
So many times, we only focus on the scale and not the free fat mass or the lean muscle mass lost. If you are losing weight at a rapid pace (unless you are really overweight), then this is probably not a good thing at all. This means that a lot of the weight that you are losing is muscle, and that is the last thing that you want. That is not going to give you the body composition that you want, that is going to lower your metabolism so that you have to eat less in the future to be able to lose, and it's not good for you in the long term as well leading to complications. Long story short that isn't really related to carb cycling-you want to lose weight slowly and steadily and keep as much muscle as possible.
Will carb cycling help this? Possibly but probably not. Many studies have shown that increased carbs help with retention of muscle, so therefore you are going to need carbs to retain muscle mass while you are dieting. So, maybe the addition of a refeed day will allow you to get carbs in however again, you could spread those carbs out all throughout the week, and the results should be the same, and you might be happier every day.
There are some people who just genuinely enjoy carb cycling. They may not like to eat a lot on certain days and then they like to load on other days that they may have a heavy workout, which is totally useful in it's own place, and totally fine.
I just don't want people to think that carb cycling is magical.
If you are someone that is an endurance athlete and you have a large swinging amount of expenditure on different days, then carb cycling is obviously going to be something that you should implement (that's what my Advanced Endurance Program is all about). This is carb cycling, however I honestly don't even think of it as carb cycling, but rather just eating to what your needs are for that day. I know that there are tons of athletes that do not track their nutrition and don't worry about how much they are getting on these longer workout days, but that is why I love tracking so much for endurance athletes. It really gives targets so that they are able to get ENOUGH nutrition. Most of the time, women are not going to eat the amount that they should for the amount that they are expending in ironman training. It's almost difficult to eat enough, but as I stated before, it's so important to not lose muscle mass, and in order to not lose, you have to eat carbs. Once you have burned through those carbs, your body will start to break down muscle.
So, do I ever put my clients on a carb cycle? Rarely but absolutely!
I'm never going to start someone on a carb cycle unless of course they have a large range of expenditures on different days. You want to just get stable on a normal amount. Having cheat meals is not my thing, but some want that for their mental state. That is the reason for it - mental stability. A cheat is not going to help you with weight loss other than to just give you a break but it's a really wide spread belief by some that having more one day per week helps them to lose weight quicker, but it's the same concept as carb cycling-there is no proof when put to the test of this. I like to get clients on an amount of intake that they can maintain every single day even into the weekend so that they are able to get stable and stay stable and just live their lives while also reaching goals.
There are times when carb cycling is useful, and if you are someone that has tried it and loved it then I'd love to hear about your experience because as I said, I'm not trying to put it down. I hope this is helpful for those though that might be considering it.