"Protein alone isn't enough! Many people make a major mistake when trying to lose weight!"

Seven-time Mr. Olympia Arnold Schwarzenegger is one of the most prominent figures in the history of bodybuilding. Although he is now 79 years old, he remains actively involved in fitness and regularly shares the latest scientific findings through his newsletter, Arnold’s Pump Club. In the November 4, 2026, issue, he focused on a problem many people face while on a weight-loss diet.

They try to consume enough protein, but at the same time restrict their calories so much that they don’t have enough energy left for a high-quality workout.

According to Arnold, simply consuming enough protein doesn’t guarantee that your body will function properly during high-intensity physical activity. Total energy intake and adequate carbohydrate intake also play an important role.

Researchers compared three diets. The results were surprising!

Arnold based his recommendation on a randomized study published in 2026 in the *European Journal of Sport Science*. Researchers monitored 19 physically active adults who followed three different five-day dietary regimens. The first regimen provided sufficient energy, the second significantly restricted energy availability with a proportional reduction in all macronutrients, and the third maintained protein intake but at the expense of greater restrictions on carbohydrates and fats.

The researchers then compared their performance during an intense test on a stationary bike.

And this is where a significant difference emerged!

With a significant caloric restriction but maintained protein intake, participants experienced a decline in performance during a 30-second sprint compared to the regimen with adequate energy intake. However, when protein, carbohydrates, and fats were restricted proportionally, the researchers did not observe a similar statistically significant decline in sprint performance.

The results suggest that with an extreme diet, the problem may be not only a lack of total energy but also an excessive restriction of carbohydrates.

Why are carbohydrates so important?

Arnold pointed out that carbohydrates are an important source of energy, especially during intense physical activity. During strenuous strength training or repeated sprints, muscles also utilize energy stored in the form of glycogen. If you significantly restrict carbohydrates over the long term, it may be more difficult to maintain high intensity during repeated exertion.

However, this does not mean that protein is any less important!

In fact, adequate protein intake plays a crucial role in maintaining muscle mass during a weight-loss diet. Arnold’s recommendation, therefore, is not to replace protein with carbohydrates, but to properly balance the entire diet. Furthermore, the study itself only tracked short-term changes in performance among a small group of participants. Therefore, it’s not possible to automatically draw conclusions about long-term muscle growth or fat loss from it.

Want to lose weight and train effectively at the same time? Arnold recommends an easier approach!

According to Schwarzenegger, when trying to reduce body fat, it makes much more sense to start with a milder calorie deficit. This approach allows you to consume enough protein while still leaving room for carbohydrates, which are essential for intense training.

An overly aggressive diet doesn’t necessarily lead to better results.

On the contrary, it can lead to increased hunger, fatigue, and difficulty maintaining training intensity. A more moderate calorie deficit also provides more room for gradual adjustments to your diet in case weight loss stalls. Arnold thus highlights an important fact that is often overlooked in weight-loss diets.

It’s not enough to just watch the number on the scale or meet your daily protein intake. It’s also important to have enough energy for a high-quality workout and a long-term, sustainable routine.

How can you get enough protein and carbohydrates while on a weight-loss diet?

If you work out regularly and are trying to lose body fat at the same time, you don’t automatically have to cut out carbohydrates or drastically reduce your food intake. It’s more important to distribute your calorie intake appropriately and choose foods that will help meet your body’s needs.

GymSupps XWhey Protein, which combines whey concentrate, isolate, and hydrolyzed protein, can help ensure you get enough protein. According to the manufacturer, one 30-gram serving contains approximately 22.5 grams of protein, which contributes to the growth and maintenance of muscle mass.

For a convenient carbohydrate boost before a demanding workout, try Kulturistika.com New 100% Rice Porridge, a smooth rice porridge containing 79 grams of carbohydrates per 100 grams of product. Combining these two foods can be an easy part of a diet whose total energy intake aligns with your goal.

Weight loss isn’t a race. Long-term consistency is what matters!

Arnold Schwarzenegger reminded us in his latest recommendation that a successful weight-loss diet isn’t just about minimizing calorie intake. If you want to lose body fat, maintain muscle mass, and perform well in sports, you need to think about your diet as a whole.

Protein is important, but on its own, it cannot replace the energy your body needs during intense training.

So perhaps it’s not necessary to keep eating less and less. Sometimes a sensibly planned diet that you can stick to long-term—without unnecessarily sacrificing your performance at the gym—can be a much better approach.