Common Nutrition Myths... Busted

多种运动

September 18, 2024

As a leading sports nutritionist, Renee McGregor encounters plenty of misconceptions about fueling, training, and nutrition in general. Here, she addresses five of the most common myths she has to address.

Myth One: Being light makes you faster

Weight loss is a complex subject, both physiologically and psychologically.

There is no doubt that in the Western world, there is a societal bias towards a particular body type and size. Despite campaigns to change these attitudes, the dominant message is still that a smaller body is more acceptable. And yet our body size tells us very little about who we are.

Our bodies need a huge amount of energy to maintain daily biological processes, and this is further increased when we are physically active. What few people stop to consider is that a series of chemical reactions - including at a cellular level - need to occur for effective adaptation and progression in your training.

So while we may initially see benefits to being in a smaller, lighter body, this is not sustainable especially if we move too far away from our natural point. Once the body identifies that the deficit is too big to maintain, it switches on compensatory behaviors that start to down-regulate the body to preserve energy. The individual may function, but they will not thrive or meet their sporting potential.

Myth Two: Rice is better to eat than pasta as it doesn't spike insulin

Rice and pasta have the same impact on your body's glycemic control – you can use whole-grain versions of pasta to slow down the breakdown of carbohydrates into glucose in the body.

However, in some situations, such as before a ride or in the immediate recovery phase where elevating insulin also helps with the uptake of carbs and protein required to allow for glycogen replenishment and muscle repair, white varieties will be more appropriate to support performance.

Myth Three: You should eat less carbohydrates and calories on rest days due to a higher level of inactivity.

This is often bandied around, but the reality is that if you are training most days, your recovery day is the time to continue to refuel after a hard effort and also prepare for your next day of training. It is also important to remember that most adaptation to training occurs on our rest day, and this is often why many of us will have a higher appetite on these days.

Myth Four: You should eat larger meals for lunch directly after training and less for dinner

Ideally, we should be fuelling our bodies based on our training needs – this may mean a larger meal to help recovery at lunchtime but doesn’t necessarily mean less at dinner. If you fuel appropriately around your training, your body can adapt and achieve its optimal place for performance.

Myth Five: Calories in versus calories out

A calorie is defined as the amount of heat needed to raise the temperature of one kilogram of water from 0 to 1 degree Celsius. Thus, a calorie is a unit of energy or heat that arises from the combustion of the nutritional components of our diet.

We need calories to provide us with the energy required to live. Every single biological process in the body requires energy, and this has to come from the food we eat.

The problem is that humans are not calorimeters, and how we utilize food is very different to simply burning and providing energy. As an example, let's take the humble carrot. Calorie tables tell us that 100g of carrots provides us with 10 calories. Now while this is true, when you burn carrots in a calorimeter, it is not the same in a human. Carrots are predominantly indigestible by the human gut so when we consume 100g of carrots, we only absorb a very small amount of those 10 calories. This is problematic for those of us who are physically active because if we consume too many vegetables we may displace our intake of carbohydrates and struggle to consume the actual amount of energy we need to support our body.

Written by

Renee McGregor

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