When it comes to losing weight and burning fat, not all fats are created equal. Some types of fat are more difficult for the body to mobilize and use for energy than others. Understanding the differences between different types of fat can help guide nutrition and exercise strategies for maximum fat loss.
Types of Fat in the Body
There are several main types of fat in the human body:
- Subcutaneous fat – Fat found just under the skin, particularly in the thighs, hips, buttocks, and abdomen. This fat protects internal organs and insulates the body.
- Visceral fat – Fat found deeper inside the body, surrounding internal organs like the liver, pancreas, and intestines. Excess visceral fat has been linked to several health issues.
- Brown fat – A special type of fat that generates heat and helps regulate body temperature.
- Intramuscular fat – Fat droplets found within muscle tissue. Small amounts may provide energy for muscles, but excess intramuscular fat can cause insulin resistance.
Which Type of Fat is Most Difficult to Burn?
While all types of excess fat can be lost with the right diet and exercise program, some fats are more stubborn than others. Two of the most difficult fats for the body to mobilize and burn are:
Visceral Fat
Visceral fat is notoriously hard to lose. Also known as “belly fat,” visceral fat collects deep inside the abdominal cavity and surrounds organs like the liver, pancreas, and intestines. It has been strongly linked to diseases like type 2 diabetes, heart disease, and some cancers.
Unfortunately, visceral fat is metabolically active – it releases hormones and immune system chemicals that can negatively impact health. And it’s located deep within the body where blood flow is lower, making it harder for the body to access and burn those fat stores.
Losing visceral fat requires a sustained calorie deficit, along with strength training and high-intensity exercise to boost metabolism and burn calories. Even with consistent diet and exercise, visceral fat can take weeks or months to fully mobilize.
Intramuscular Fat
Intramuscular fat (IMF) is found within skeletal muscle tissue in small lipid droplets. IMF provides a local energy source for muscles during exercise. But in excess, intramuscular fat can cause insulin resistance which makes fat loss more difficult.
Because intramuscular fat is located within muscle tissue rather than in adipose tissue, it can be very stubborn to lose. The body preferentially taps adipose tissue stores for energy before digging into IMF stores.
Building muscle with strength training is one of the most effective ways to reduce IMF. As muscles grow larger, intramuscular fat droplets shrink relative to overall muscle size. High-intensity interval training can also help reduce IMF. But consistent strength training over a long period is usually needed to substantially decrease IMF.
Other Difficult to Burn Fats
While visceral and intramuscular fats are particularly stubborn, other types of fat can also be challenging to fully lose:
Thigh and Butt Fat
Subcutaneous fat in the hips, thighs and buttocks often represents a feminine fat pattern. Because estrogen promotes fat storage in these areas, this fat can be difficult to lose for many women. Liposuction is sometimes used to remove stubborn hip/thigh fat. But diet, aerobic exercise, and strength training tailored to the lower body can all help burn thigh and butt fat over time.
Back Fat
Subcutaneous fat on the upper and mid back is another stubborn zone, particularly for men. But this fat will shrink gradually with an overall reduction in body fat percentage through proper diet and exercise. Building the back muscles with rows, lat pulldowns, and other exercises can also help improve back fat appearance.
Chest Fat
Subcutaneous fat on the chest and upper abdomen can create the appearance of “man boobs” or “moobs” in men. Losing overall body fat while also strengthening the chest muscles with bench presses, push ups, etc can reduce the look of chest fat. In some cases, liposuction is used for severe gynecomastia.
Why Do These Fats Get Deposited?
There are a few key reasons why the body tends to store higher amounts of fat in visceral depots and muscles:
- Hormones – Hormones like cortisol and estrogen promote increased visceral fat storage, especially in women.
- Genetics – Genes play a major role in determining the pattern of fat distribution and storage among individuals.
- Diet – Chronic overeating and a diet high in sugars/refined carbs is linked to elevated visceral and intramuscular fat.
- Inactivity – Lack of exercise leads to greater visceral fat accumulation over time.
Making smart nutrition choices and staying active can help prevent excess buildup of difficult-to-burn fats over years and decades. It’s much easier to maintain healthy fat levels than to try to lose large amounts of stubborn body fat later on.
Strategies to Burn Stubborn Fat
While challenging, it is certainly possible to get rid of stubborn visceral and intramuscular fat through the right dietary strategies and exercise regimen:
Follow a Calorie Deficit
Creating a daily calorie deficit through diet and exercise is vital for losing fat from any region. Aim for a 300-500 calorie deficit per day to lose about 1/2 to 1 pound per week. Tracking calories and macronutrients can help stay on target.
Increase Protein Intake
Eating more protein (1.6-2.2 grams per kg of body weight) helps preserve lean muscle mass in a calorie deficit while maximizing fat burning. Protein also suppresses appetite by regulating hunger hormones like ghrelin.
Limit Refined Carbs
Minimizing intake of refined carbs like sweets, chips, pasta, breads, etc. can help reduce insulin levels and allow for greater mobilization and burning of stored fat.
Do HIIT Workouts
High-intensity interval training (HIIT) burns more calories and boosts metabolic rate compared to traditional moderate-intensity continuous training. Plus, HIIT helps reduce intramuscular fat within muscles.
Lift Heavy Weights
Progressive strength training helps build muscle and raise daily calorie burn. Lifting heavy also directly burns intramuscular fat as muscles adapt to high-intensity training stress.
Add Cardio Exercise
Moderate to high-intensity aerobic exercise (like running, cycling, or rowing) is optimal for burning visceral fat. Aim for at least 150-300 minutes of cardio per week.
Reduce Stress
Chronic stress exposure promotes visceral fat accumulation. Meditation, yoga, deep breathing and other stress relief tactics can help lower cortisol and reduce belly fat storage over time.
Conclusion
Visceral fat and intramuscular fat tend to be the most difficult types of body fat to get rid of. Genetics, hormones, poor diet and a sedentary lifestyle promote greater visceral and IMF storage. But adopting an exercise routine that combines strength training, HIIT and cardio along with a high-protein, low-carb nutrition plan can help shed stubborn fat from the abdominal cavity, muscles and other problem areas. While losing the last bits of visceral or intramuscular fat may take months, consistency with diet and training is key for getting lean.
References
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