Intramuscular fats, intramuscular triglycerides IMTG (intramyocellular triacylglycerol or intramuscular triglyceride), IMAT (intramuscular adipose tissue) are a local source of energy for endurance work. Their number depends on the type of training, it is greater in endurance athletes (marathon, half-marathon, triathlon, cycling).
Most of this fat is stored in slow fibers, because triglycerides are not suitable as a source of energy for very intense, short-term work. In healthy, physically active people – this fat is of little importance, I will say more – in athletes it is more the better (the collected IMTG demonstrates adaptations to endurance training, eg long-distance running or triathlon!).
In turn, many studies indicate that in pathological conditions the amount of fat inside the muscles is of health importance. In addition, fat has many types and not everyone is harmful to health.
What we know now
High-fat diets and diets in which the calorie increase is increased by carbohydrates contribute to the accumulation of fat inside the muscles. A short-lived fasting also increases the amount of IMTG. In healthy athletes, this deposition of fat should not matter, otherwise this issue is in people who are ill.
You can read also: The role and qualities of fat in the diet