You’re at the start line ready to perform.
You’ve trained with purpose.
You’ve prepared your equipment.
You’ve got a nutrition race strategy. You know what’s in your bottles and in your pockets but have you packed extra fuel in your muscles and liver? It might come in handy for the long road ahead.
If you want to deliver a big endurance performance then you might want to consider carb loading. It’s a valuable pre-race nutritional strategy – if you are a man.
Less so for women, but we’ll talk about that.
Regardless of the endurance sport you are in, if you decide to carb load, make sure you do it properly.
It relies on two essential components.
Carbohydrate is the body’s preferred currency for energy production.
We get it from what we eat, drink, and our limited carbohydrate stores (called glycogen) in muscles and liver.
Our liver glycogen is used to power our body processes when we sleep. It is replenished through our daily diet.
Our muscle glycogen is used during exercise. It is replaced during recovery.
The amount of glycogen we can store is dependent on how much muscle mass we have. It ranges between 300 – 600 grams, the equivalent of 1200-2400 calories.
In an endurance event, glycogen plays an important role in closing the inevitable energy shortfall. The more glycogen you have in your muscle bank, the more able you are to go the distance.
Carb loading is a nutritional strategy whereby the muscles and liver are forced to temporarily increase the amount of stored glycogen by up to 30-40%.
To do it effectively you first must deplete glycogen stores.
This is the step that most people miss.
You can deplete glycogen in a couple of ways.
You can increase the volume or intensity of exercise but this could be counterproductive, given that you are in a pre-race taper phase.
You can decrease the amount of carb you are eating or you can do a combination of both.
Once glycogen stores are depleted, you significantly increase carbohydrate intake. This forces the liver and muscles to over-compensate and temporarily increase storage capacity for glycogen.
On day 1-3 decrease carbs to 20% of your usual intake, whilst maintaining your taper activity.
On day 4-6 increase carbohydrate intake to a whopping 9-10g carb/kg of total body weight, while stopping training.
On day 7 you race, fully loaded and rested!
To be fair taking 6 days to do this seems obstructive amidst the busyness of getting ready to race. You may be in transit, you may have many different competing priorities, or the reduction of carb may just feel uncomfortable.
I favour the simplicity of this protocol as endurance athletes won’t typically baulk at the thought of a 2 to 3-hour training session.
On day 3 do a fasted (or very low carbohydrate) two to three-hour moderate training session. This will significantly deplete glycogen stores.
Try and eat low carb (around 30% of your usual carbohydrate intake) for the rest of the day.
During the next two days increase carbohydrate intake to that whopping 9-10g carb/kg of total body weight. Do not train on these days.
On day 4 you race, fully loaded and rested.
You can just stop training but maintain, even increase carbohydrate levels moderately, but the impact will not be significant. Many athletes do this.
Think about the quality and type of carbs you are using to load. It’s not about piling in crappy carbs that come with increased fats, like biscuits or ice cream. Sorry, you have to wait post-race for that!
You also don’t want high fibre carbs as you run the risk of gut discomfort from extra volume, plus you increase the need to ‘jump the hedge’. That’s counterproductive.
You want to hit that 9-10g carb/kg body weight using specific, low fibre carbs like fruit smoothies, white noodles, white pasta, white rice, white bread or bagels, peeled potatoes, etc.
You can maintain your normal carbohydrates like oatmeal and veggies too.
Remember we are simply increasing carbs using the above foods temporarily to force your muscles and liver, in response to depleted glycogen reserves, to increase their glycogen storage capabilities.
Remember that glycogen is hydrous, meaning that it is stored with water molecules. One gram of glycogen is stored with 3-4grams of water.
That means you will see the scales tip upwards as you store more glycogen.
Worry not, it’s all temporary and you can be sure that those water molecules count towards hydration – it’s a double fix!
Our muscles are primed to fuel differently.
We don’t use glycogen as much to ease our energy shortfall, therefore we don’t store as much.
Our muscles are primed to use circulating blood glucose first, so ingested carbohydrate is critical. This is especially true for women going through peri-menopause and post-menopausal women.
Women typically ease energy shortfalls using fatty acids, from metabolised body fat.
In fact, one of our strengths as endurance athletes is that we are highly effective at accessing and metabolising body fat for fuel.
So instead of carb loading, women need a focused race plan that delivers enough consistent carbohydrate – the amount of which is personal to that athlete – that both fuels the effort and supports the processes that metabolises body fat for fuel.
If you’re getting ready to race and have questions, you can reach me at jill@barrultra.com
But more importantly, if you want to learn how best to fuel, recover and adapt to your training load so that your endurance performance progresses – that’s exactly what I do.
I create personal nutrition plans for endurance athletes of all kinds – cyclists, runners and multi-day or multi-discipline racers.