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Why Eating A High Fat Meal Before Exercise Is A Bad Idea

We’ve all made pre-workout nutrition mistakes at some point: either eating way too much before exercising, or eating something that just doesn’t sit right. Cramps, nausea, indigestion and even running to the loo ensue — it’s not fun.

A good pre-workout meal or snack is the key to a good training session, so it’s important to know the ‘rules’.

“The key elements of pre-workout nutrition are largely dependent on the type of training the person is about to do, what the individual likes to eat and what goals they have,” Jessica Spendlove — accredited practising dietitian, accredited sports dietitian and nutrition consultant — told HuffPost Australia.

“In general, a pre-exercise meal or snack should contain some carbohydrate, protein and fluid.”

If you are eating a meal before training, the purpose of this pre-workout nutrition is to ‘prime’ the body to train. In order to do that, the food needs to be digested and ready to use.

What we should be focusing on before a workout is fuelling with carbs.

The most important element for a pre-workout is carbohydrate. This is the main type of fuel that your body is going to be using during that activity. What you have also depends on how long before the activity that you’re eating.

As a general rule, eat your pre-workout snack at least an hour before exercising.

The composition of a pre-workout meal is influenced by the type, duration and intensity of training. It is also dependent on what goals we have for the session and our overall body composition goals.

Resistance/Weight Training

Protein will be found in most carbohydrate-rich whole foods anyway, but if it’s a more resistance-based training type activity, including protein-rich foods is important, as well.

HIIT-Style Training

For high intensity style sessions, Spendlove recommends opting for a lower fiber source of carbohydrate as these are easier to digest. This includes white rice, rice cakes and potato.

Long Cardio Training

For long cardio sessions, choose higher fiber carbs (such as whole grains and legumes) and also include some protein in your pre-workout snack.

“For a long, steady state cardio session (more than 90 minutes) I would recommend a meal or snack which has a good quality, slow release carbohydrate and some protein. This will help sustain the rate at which energy is released and not spike blood glucose levels,” Spendlove said.

Short Cardio Training

“For a steady state aerobic session lasting around an hour, it might be beneficial for the person to go in fasted,” Spendlove said.

“It is important to start any workout hydrated and to replace fluids throughout. In most instances water will suffice.”

Not fueling properly before training can compromise what you get out of your training session.

When we don’t fuel correctly there are a few things that happen. Number one, you won’t perform as well because you’re fatigued and don’t have enough energy. It also increases the risk of getting sick because you’re putting stress on your body. Also, you can end up feeling pretty unwell, depending on how it is that you haven’t fueled properly.

Not fueling or hydrating properly before training can also result in reduced speed (especially during repeat efforts), reduced endurance, poor concentration and decision making, skill errors or suboptimal body composition, Spendlove explained.

“This means the person may not get the most out of their session, and over time this means they might not improve their fitness goals to their potential (be it speed, strength, body composition adjustments).”

“If someone is aiming to put on lean mass, not having a good pre-workout meal can compromise the changes to body composition they are trying to make.”

This is where fat comes in. Although healthy fats are an important part of our overall diet, eating high fat meals or snacks before exercising can compromise your workout.

“Fat is a nutrient which slows digestion. The more fat in a meal, the slower the meal is digested,” Spendlove told HuffPost Australia.

“If you are eating a meal before training, the purpose of this pre-workout nutrition is to ‘prime’ the body to train. In order to do that, the food needs to be digested and ready to use. If the pre-workout meal has not been digested, it will not provide ‘fuel’ for the session.”

Eating meals high in fat prior to a workout is more likely to be undigested and sit in our stomach during exercise. As such, it can also cause some uncomfortable gastrointestinal symptoms, such as nausea, vomiting or diarrhea.

However, if you do want to include fat in your pre-workout — whether it’s avocado, nuts, peanut butter or olive oil — make sure you allow 1½-2 hours before exercising.

So, what are the best foods to eat before a workout? While there’s no one ‘perfect’ pre-workout snack, choose food that’s enjoyable, comfortable and easy to digest.

Here are some more easy pre-workout meals and snacks:

  • Greek or natural yoghurt with untoasted muesli and fruit
  • Pre-workout smoothie (coconut water, frozen banana, crunchy natural peanut butter, vanilla vegan plant protein)
  • Oats with banana, milk and honey
  • Cottage cheese with tomato on Vita-Weats
  • Good quality bread with banana and honey
  • Tuna with rice cakes
  • Banana with a glass of milk

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