What Good Nutrition Really Does for Your Fitness

You train regularly, give it everything at the gym or on your runs, and yet you still wonder why progress is taking its time? Then it's worth taking a look at your plate. Because fitness doesn't come from movement alone, it also depends heavily on what you eat and drink.

Two thirds nutrition, one third exercise?

Experts in nutrition and sports medicine estimate that physical fitness depends roughly two thirds on nutrition and only about one third on exercise. That sounds surprising at first, doesn't it? But above all it means one thing: you have far more influence over your fitness than you might think, and you get a fresh chance every single day, at every meal.

The IOC consensus statement on sports nutrition highlights exactly this: tailored nutrition strategies before, during, and after training can help you make the most of your physical and mental performance.

Energy: the engine for your training

Exercise raises your energy needs. If you eat too little, the very thing you want to avoid can happen: your body breaks down muscle and your performance drops. Over time, this can even affect your health. A sufficient and balanced diet is therefore the foundation for going into training in good shape in the first place.

Complex carbohydrates from whole grains, fruit, vegetables, and legumes are especially valuable here. They give you long-lasting energy instead of short-lived sugar spikes. As an endurance athlete in particular, you benefit from a higher proportion of carbohydrates in your daily diet.

The three macronutrients at a glance

For your fitness, all three major nutrients matter together, not just one on its own:

• Carbohydrates: Your most important source of energy. They can even support fat burning, especially in their complex form from whole grains and the like.
• Proteins: The building blocks for your cells and muscle tissue. After training, your muscles need enough protein to recover and rebuild.
• Fats: Healthy, unsaturated fatty acids from nuts, avocado, or flaxseed are essential for your cell function and support your performance. Nutrition guidelines for athletes generally suggest around 20 to 30 percent of total energy from fat, with a health-friendly fatty acid profile. Trans fats and highly saturated fats are best kept to a minimum.

How much protein do you really need?

There are plenty of myths around protein. Do you really need a double protein shake after every session? Not really. The general recommendation is around 0.8 g of protein per kilogram of body weight per day, which corresponds to roughly 12 to 15 percent of your total energy intake.

At a high performance level, needs can rise to 1.2 to 1.7 g per kilogram. Even so, a normal, balanced diet is completely enough for most people, and even for many competitive athletes. There's no evidence that extremely high amounts of 3 to 4 g per kilogram bring extra muscle.

You'll find good protein sources in everyday foods:

• Animal-based: Eggs, lean meats such as poultry, fish, and low-fat dairy.
• Plant-based: Legumes, whole grain products, and potatoes.

Don't forget: drink enough

Water is good for you, and that's especially true during exercise. Drinking enough is important for your performance, and above all you should already be well hydrated before you start. Isotonic sports drinks with carbohydrates and electrolytes are usually only needed for longer efforts of over two hours, or for intense sessions well over an hour. For most workouts, water is perfectly enough.

Fat loss: nutrition and movement hand in hand

You lose fat when you use more energy than you take in from food. What matters is the combination of a healthy diet and movement, not deprivation at any cost. A moderate calorie deficit, combined with endurance training and two to three HIIT sessions a week, is a good approach.

Fibre helps too: in one study, increasing daily soluble fibre intake by 10 g was linked to a 3.7 percent reduction in the build-up of visceral fat. Another reason to reach more often for whole grains, vegetables, and legumes.

Timing and myths around eating before exercise

Can you eat before training? Absolutely. A light, carbohydrate-rich snack can even give you extra energy and support fat burning. It's only large, heavy meals right before exercise that put a strain on your digestion. So it's not about a ban, but about the type and amount of your meal.

And the famous post-workout protein shake? It isn't strictly necessary. Nutrition guidelines generally favour getting your protein through a balanced diet. Extra high-quality protein can make sense with a very high training volume, but for most people it isn't a must.

Do you need supplements?

In the vast majority of cases, the answer is: no. Nutrition guidelines emphasise that a balanced, varied diet is enough to deliver top performance even in competitive sport, with no supplements at all. Your fitness is therefore much closer at hand than shelves full of powders and capsules might suggest.

Your next step

As you can see, good nutrition isn't a rigid set of rules but your strongest ally for more energy, steadier muscles, and better recovery. If you'd like to know what an eating plan that fits your training and daily life could look like, our nutrition coaches are happy to support you step by step. Just send us a message, we'd love to hear from you!

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