I remember when I saw my first ab vein. At that point in my life, I just wanted to get super lean to prove to myself that I could. The thin bluish line across my abs was the sign I’d been looking for. I’d bought a ticket to shreddsville, and this time, the train had pulled into the right station. The weeks of dieting up until this point had been based on information I’d found in Internet forums (yes forums. I’m old enough to have spent way to much time looking for answers in the wrong places), and the protocol was just difficult enough to make a geek like me buy into it. If it seemed complicated, it should work, right? The problem wasn’t that it didn’t work, the problem was what it made me believe.
The approach was termed “carb cycling”, which really just means that you have high carbs at one point, and low carbs at others. You trained with weights three times a week, and rested and did light cardio on the other days. On the training days, you got a green light to go completely wild with carbs. Boxes of cereal, bagels and jam, and all manner of goodies were thrown down the hatch. Training, apparently, meant my muscles would be ready to suck the epic sugary bounty up, helping me recover, and build muscle. While carbs immediately after training were great, carbs at any other time would result total disaster. Without the muscle sensitising workout, I was led to believe the sugar would all turn to fat, and any chance of having shredded obliques would be lost. As far as I was concerned, my weight loss was all about when I ate carbs, and when I didn’t. I’d forgotten about the most important thing; Calories.
Approaches like this are far more mainstream than you might think. The idea that exercise determines if carbs are good or bad, is often a point of discussion in my consultations. In fact, several of my clients had come to me after trying the lean in 15 approach, and all of them fell for the same trap; that carbs outside of a tiny window around training will decimate their blood sugar, and transform into fat before their eyes. As was the case with my carb cycling experience, the emphasis is on low carb and higher fat days, with carbs only eaten after training. Again, the bigger picture of overall energy balance has been overlooked, in favour of specific food choices at specific points. Let’s see why this is a mistake.
As well as the glucose in your bloodstream, your body stores carbohydrates in your liver and muscles as glycogen, which you can think of as being like human starch. Topping this up after training seems like a good idea then, but how depleted are these stores in the first place, and how soon should you eat carbs after training? If you’re lifting weights, the answer to both of these questions might not be what you’d expect.
- A study by Roy and Tarnopolsky from 1998 showed that doing full body training of 9 exercises for three sets each depleted only about a third of the body’s muscle glycogen. If I had known this during my carb cycling trip to lean town, I might have been a little bit more careful with the post workout cocoa-pops.
- In fact, Pascoe et al, showed that after training legs until total failure, 75% of the glycogen that was depleted was restored after 6 hours without eating anything at all.
- Weight training just doesn’t burn as many Calories as you might think. A 90kg man will be lucky to burn somewhere between 300 to 500 Calories in a training session. You don’t need to go to bagel crazy to put that back in.
Where you really can plough through some glycogen is with stop-start exercises.
- High-level soccer matches can deplete muscle glycogen by 50 to 90%
- As little as 2 30 second cycle ergometer sprints can deplete the glycogen in your quads by 44%.
If you’re doing this kind of exercise, it might seem like it’s definitely a good idea to start throwing down post-workout packets of Haribo. However, it’s still not the case.
- If you’re doing multiple hard exercise sessions on the same day, training the same muscle groups, then the immediate use of carbs after training is a good idea.
- If you’re training again tomorrow or having a day between sessions, just eating your regular diet will be enough to “recover” without any need for carb mega doses, sports drinks, or boxes of cereal.
“Giving your muscles a little injection of carbohydrate”, so that they can “shuttle the protein straight from your meal into your muscles” sounds great on paper, but as is so often the case, it’s a load of old horeshit.
- Koopman et al. (2007) tested whether 25g of protein taken with either no carbs or 0.15g and 0.6g per kilogram of bodyweight. They found that “co-ingestion of carbohydrate during recovery does not further stimulate post-exercise muscle protein synthesis when ample protein is ingested”. Perhaps carbs don’t need to be there to shuttle protein into your muscles after all.
- A few years later in 2011, Staples et al. found that 25g of whey protein along with 50g of carbs didn’t stimulate protein synthesis more than 25g of whey protein alone. Where troughing down pic n mix after training for extra gains was concerned, this study was the final nail in the coffin.
Once I’d learned that carbs after training weren’t hugely beneficial for recovery, and weren’t doing jack shit for muscle growth, you might have thought I’d be a little bit more liberal with carbs on rest days. You know, have a piece of toast or something, live a little. Well, not this guy. I wasn’t sold yet. Maybe carbs weren’t quite as helpful as I once thought, but that doesn’t mean I was going to start shovelling them in with gay abandon. If there was one thing the forums were clear about, it was that carbs anywhere away from training were going to turn straight to fat, and I was not ready to risk that kind of thing. It turns out, however, that I was wrong again, and it was still all about Calories.
De Novo Lipogenesis is a fancy schmancy term for the conversion of excess carbohydrates to fat. You might think that if you eat enough carbs, that they will almost certainly turn to fat, but in actual fact, you need to eat a huge amount of them before any are added to your love handles at all.
- In a study by McDevitt et al. overfed people by 50% for 96 hours with either glucose or sucrose
- Even though they ate 360 to 390g of carbohydrate, the conversion of carbs to fat per day only ended up being 3 to 8g.
- Instead of turning carbs to fat, your body is much more likely to up-regulate the amount of carbohydrate it burns.
- In a study by Acheson et al. people were progressively fed an 86% carb diet containing 3,642 kcals to 4,930 kcals over 7 days.
- The number of carbohydrates burned in the body went from 74g per day to 398g.
- Carbs only started to be turned into fat when glycogen stores had increased by 500g. Not an easy feat.
People in both of the above studies gained fat, but it wasn’t because of carbs, it was because energy intake was way greater than energy output. In a surplus of Calories, the fat you eat is very easy to store. Your body would much rather do that than messing around turning carbs into fat. The key to fat gain and loss is, as always, energy balance.
My carb cycling protocol worked, just not for the reasons I thought. I lost fat because I consumed less energy than I burned over the course of a week. Not because of when I ate carbs, or when I didn’t. These days, I can manage to see ab veins while eating whatever kind of carbs I like, whenever I like. You can do that too if you pay more attention to the energy content of your food and less attention to when you eat it.
Despite what you’ve heard, there is no special benefit to eating carbs after training, and absolutely no reason to not eat them on rest days. Carbohydrates contain energy, just like any of the other macros, and it’s this that that makes them problematic for your waistline if you eat too many, and nothing else.
Build a roadmap to your physique and health goals now and learn the skills to stay on the path forever: