Can high, low and moderate carb days power your workouts and help with weight management, or is it a waste of time? Here’s how carb cycling works, when it works, and why it’s not for everyone

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Carb cycling: it’s not eating a bread loaf on a bike, rather alternating the amount of carbohydrate you consume depending on your activity levels. Registered Nutritionist  Daniel O’Shaughnessy  explains the concept in a nutshell:

“Carb cycling can be structured in a number of ways but it usually involves having low days of carbs, moderate days and high days of carbs during the week. People tend to have a higher quantity of carbs when they are working out a lot and then lower their intake on their rest days. For example, leg day in the gym would probably be on a high day, while if you’re sat at your desk for prolonged amounts of time, that would likely be your low carb day.”

Essentially, carb cycling is a more extreme take on the old ‘energy in vs. energy out’ idea of weight maintenance and loss, designed to optimise your carbohydrate load so that you’ve got plenty of fuel to burn when you’re midway through HIIT , but won’t store excess carbs as fat on down days. It’s the Joe Wicks  way, practised by elite athletes and can boost workout performance while helping you to build muscle and maintain a healthy weight. Right now, it kind of sounds like a diet utopia- you can have your carbs and eat them too, and low carb days are infrequent enough to be livable so there’s none of the Atkin’s associated misery/ deprivation/ bad breath/constipation/total carb avoidance. As always with anything positing to offer up the perfect healthy living solution, however, carb cycling isn’t an approach that suits everyone. Here’s your carb cycling 101, but always consult your GP before dipping a toe in any diet, particularly if you suffer with a health condition.

A week in the life of a carb cyclist

Just what does carb cycling look like on a plate? Daniel underlines the basic structure:

“A typical carb cycling week could entail two high carb days, two moderate carb days and three low carb days. You still hit your calorie quota on lower carb days as generally you’ll be eating more fat than on higher carb days.”

Exactly how many carbs you eat will depend on your level of activity, body weight and aims, and quality is as vital as quantity- slow release carbs, wholegrains and starchy vegetables and pulses should be your port of call over refined carbs such as pastries, cakes, biscuits and sugary cereals, but then you knew that already. The British Dietetic Association  recommends consuming a fist-sized portion of starchy or wholegrain carbohydrates per meal as a baseline, adjusting this depending on energy levels. As such, this would likely constitute your moderate carb day if carb cycling.

Where did carb cycling come from?

We’ve all heard of carb loading  before a fitness challenge and the popularity of low carb diets such as the Dukan diet, ketogenic diets  and of course Atkin’s for weight loss, so varying your carb intake on a daily or weekly basis to ‘optimise’ your energy levels and results is nothing new, as Daniel highlights:

“It’s commonly used in the fitness world or when on a fat loss regime. Some people turn to carb cycling as a weight loss method as an alternative to counting macros - they limit carbs to just before and after workout. The theory here is that your body is more primed to use them after exercise, rather than the carbohydrates being stored as fat. It’s really down to the individual to see if they can wait until the workout for carbs- some people need them at breakfast just to function.”

Tailoring your carb intake to your training style is common too- if you know you’ve got an intense session coming up, you may include the likes of carbohydrate gels to increase the amount of glycogen available to your muscles, thus reducing your likelihood of muscle damage and enhancing repair. In the same way, if you’re lightening the load in the gym, you might adjust your carbohydrate portions to reflect the fact that you won’t need as many calories from carbs as usual. There’s no prescriptive plan to suit everyone, but maintaining balance overall is key.

The benefits of carb cycling

If you’re a regular gym goer, switching up your carbs depending on how much you sweat could pay dividends according to Daniel:

“It can supply additional energy when undergoing intense training sessions and other pros extend to improving performance while also reducing muscle wastage, as well as helping to stabilise the appetite-regulating hormones leptin and ghrelin. Carb cycling may also help to improve insulin sensitivity  and support the metabolism so that it burns fat for fuel more efficiently, thereby speeding up weight loss.”

You may already be signing up to become a fully fledged carb cyclist, but wait right there…

Carb cycling caveats

First off, there’s not a lot of research to support the long-term success of carb cycling currently, and while in theory it’s an effective method of both weight loss and getting the most out of your workout, it could prove to be more of a headache than it’s worth at best, and at worst lead to disordered eating . Daniel outlines why tinkering with your carbohydrate servings isn’t always a cure-all:

“It’s complex to get the balance right on an individual level and there may be adherence issues for beginners. You need to count how much protein, carbs and fat you’re consuming too- apps like myfitnesspal can  help, but it’s quite time consuming and not always accurate. It’s also not really needed for the layperson who goes to the gym twice a week.”

Which leads us to…

It’s a case-by-carb basis

As with any eating plan under the sun, carb cycling will work for some and not for others, and you’ve got to be prepared to put the work in, both in the gym and in the maths department. Daniel emphasises that, while its less limiting than many other low carb diets, it requires a degree of preparation and calculation:

“I think that it takes some getting used to and the method to work out the carbs you need on any given day can be very exact in terms of counting- some people will love it, while others will hate it.

“Technicalities aside, it can be healthier than alternative diets, as even on low carb days you’re eating some carbs at least- carb cyclers often aim for around 50g of carbohydrate on low days, but again this depends on your unique needs. People also tend to eat more vegetables and lean protein and fewer refined foods and free sugars on low carb days, which is beneficial for health.

“Again, it all comes down to the individual working out which carbs work for them, and when they need energy from carbs the most. I have a lot of clients who eat carbs and then experience cravings for even more carbs throughout the day. I tend to advise them to eat their carbs in the evening, as it can often help to take the edge off of cravings and even improve results if weight loss is the goal, but then you might perform best if you have carbohydrate for breakfast.”

The bottom line

Given that many of us are eating more carbohydrates than ever, owing to a variety of factors such as increased portion sizes, a flood of added sugars in the food industry and the ‘grab and go’ appeal of refined carbohydrates in particular, carb cycling could be an effective means of monitoring our carbohydrate intake and getting the most out of the food we eat.

That said, as with any diet, it can be a tricky and not necessarily healthy regime to stick to long-term, and too many low carb days could contribute to our deficit in fibre as a nation , not to mention missing out on key nutrients and vital brain and body fuel- carbohydrates are the body’s primary source of energy according to the NHS . Being aware of how much carbohydrate is on your plate, and what from what sources, is certainly a good idea when it comes to achieving a balanced diet, but you don’t need to officially ‘cycle’ your carbs to achieve a carbohydrate equilibrium. Leave it to the pros or discuss with your GP or a relevant health expert before embarking on any dramatic carb juggling.

Fibre: are we forgetting about it?

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