Easily the most misunderstood macronutrient for athletes, fats play an important role in energy output, nutrient absorption, and even injury prevention.
For an individual performing high-resistance training, some monounsaturated and polyunsaturated fats are essential. In general, around 15–30% of overall energy intake should come from fat—though this may change depending on your genetic makeup. As we explain in Demystifying Fat: Should Fat Be Part of Your Diet?, monounsaturated and polyunsaturated fats can be found in avocados, nuts, seeds, and oils.
Omega-3 and omega-6 fatty acids are also of great importance to weightlifters. These fats can be easily sourced in fish and shellfish and help with blood flow and suppress hunger (a great assist if you’re trying to drop weight classes).
No matter your fitness goals, monitoring your intake of saturated and trans fats is important. High amounts of these fats increase LDL cholesterol levels, block arteries, and increases the risk of heart disease and stroke. Saturated and trans fats are found in chips, chocolate bars, baked goods, and butter.
A common bodybuilding nutrition strategy is bulking & cutting.
Essentially, this strategy involves two cyclical eating patterns. First, a season of bulking (eating excess calories) and then a season of cutting (eating in a calorie deficit).
In theory, during the off-season, a bodybuilder eats an excess of calories to gain overall size. By maximizing calories, they’re maximizing their energy output. At this stage, they will reach their peak performance potential but also their highest BMI.
Then, in the months or weeks leading up to competition, the athlete will severely reduce the number of calories they’re ingesting, creating a deficit of caloric input to energy output. The intended effect is to greatly lower the BMI while still having the muscular growth of the bulking period remain.
The results of this nutritional strategy can be mixed. Primarily because while the body loves burning fat, it also loves burning muscle. So during the cutting stage, many gains are often lost.