Our body needs fuel to provide us with the energy we need to practice our favorite sport, to get a HIIT workout done, or to simply go about our daily activities. In fact, even in stillness, our body requires and uses energy (BMR, i.e., our basic metabolic rate) to power our brains, organs and other bodily functions.
As you may know, there are three main types of fuel (also known as “substrates” or “macronutrients”) that our body uses to produce energy:
- Glucose (carbohydrates)
- Fatty acids (fats)
- Amino acids (proteins)
However, it’s not just the foods we eat that provide the fuel needed to function normally, our body has room for storage too. Glucose from carbs (stored as glycogen in your liver and muscles) and fatty acids (stored as triglycerides and found all over the body in adipose tissue) are stored as reserves to be used by your body under different conditions.
The fat around your midsection (i.e., that pesky belly fat) is a result of your body storing fuel that it doesn’t need right away. Bringing us to our next big question: How do we burn through body fat and where does it go when we do?
The science of fat loss
Before we answer those questions, it’s important to understand how fuel (carbs, fat and protein) is transformed into energy and in which cases they are stored as fuel. To be used by our cells, the different types of fuel must go through several stages of transformation to become the one and only form of “usable” energy: adenosine triphosphate — more commonly referred to as ATP. ATP is the universal energy currency for many living organisms from mammals to insects and fungus to plants.
To explain exactly how this works, and appease our more visual learners, we created a graphic to accompany Coach Ame’s very detailed knowledge bombs. Each number in the graphic corresponds to the details below.
Dietary fats (1)
See that food going into our character’s mouth? That food happens to be high in dietary fat. Dietary fats aren’t always bad (we talk about that in this article), but here they are ranked best to worst:
- Unsaturated fats like poly- and monounsaturated fats can lower cholesterol levels, which reduces the risk of heart disease. Unsaturated fats are typically liquid at room temperature and provide our bodies with essential fats that they can’t create on their own. These fats mainly come from plants (avocado, nuts and seeds, olive, canola, etc.) but some come from the sea too (fish and seafood).
- Saturated fats are considered healthy when eaten sparingly, but since too much consumption of these fats raises the level of cholesterol in our blood, they come with a heart disease warning. Saturated fats are solid at room temperature and come mainly from terrestrial animals and some tropical fruits (dairy, eggs, meat, coconut, cocoa, palm oil, etc.).
- Trans fats are artificially created by humans and are to be avoided as much as possible. They are used to lower the production cost of fake foods and improve the texture and shelf life of pre-made products. They have no health benefits.
Digestion of fats (4)
Your digestive system isolates fats from the other macronutrients you eat (i.e., carbs and proteins) to distribute them where you need them. But, dietary fats — those triglycerides — can’t be absorbed by your body as is, they need to go through mechanical and chemical digestion processes first.
So, digestion of fats starts in your mouth and ends in your small intestine, where it’s finally absorbed. Compared to other nutrients, fats take the longest time to digest. Here’s what the process looks like:
- Mouth (a): While we chew and break down food into smaller particles (mechanical digestion), our saliva helps by bringing necessary enzymes to start the chemical digestion of fats and other nutrients.
- Stomach (b): Once we swallow, food comes down into our esophagus and reaches our stomach where more enzymes continue to break down the nutrients.
- Liver (c): Before we even start to chew, the liver starts the digestive process. The sight and smell of food signals the liver to produce bile salts that break fat down into small droplets so it becomes more “accessible” to enzymes.
- Gallbladder (d): This bag-like organ is there to store the bile produced by our liver. This bile is essential for the digestion and absorption of fats and fat-soluble vitamins (A, D, E, K).
- Pancreas (e): This large gland hiding just behind our stomach produces other enzymes that are secreted into our small intestine to help with the digestion of all nutrients.
- Small Intestine (f): The food residue finally moves from our stomach to the small intestine where bile salts and pancreatic enzymes “liquefy” the fats molecules down to their simplest forms – fatty acids and mono– and diglycerides.
Role of fat: Energy! (7)
Fats are used by the body — together with glycogen stores — to fuel between meals, while sleeping, or when aren’t quite meeting our caloric needs. An important role of fat is to supply energy to our cells so that they can create ATP. Fat is a highly concentrated energy source but it needs to be broken down to participate in the creation of ATP. This process happens in special energy factories called mitochondria (7). We aren’t going to get into the specifics of the fat-to-ATP-process now but if you’d like some further reading, go here.
Here are some other ways fat participates in bodily processes:
- Cell membranes: Some fatty acids are necessary for the maintenance and upkeep of all the cell membranes (walls) of our body. They act like bouncers in a nightclub, only allowing the appropriate molecules to cross in and out of our cells.
- Messenger: Fat helps proteins do their jobs properly.
- Chemical reaction: Fatty acids are the starting point of many important processes happening in our body that help control growth, immune function, inflammation reactions, and reproduction.
- Ketone bodies: Ketone bodies are produced when the carb reserves (glycogen) start declining and the body must rely on fat reserves for fuel. Our liver then starts producing ketone bodies — a little molecule that can acts as a substitute for glucose (our brain’s favorite fuel). You can force your body to produce these ketone bodies by following a very low-carb, ketogenic diet.
So how does all of this relate to fat loss or weight loss? Initially, during aerobic exercise, glycogen is used. But, in its absence or when the activity lasts a long time, fat metabolism is initiated and fat is broken down to be turned into ATP. Generally, a workout performed at a moderately high level of intensity over a long period of time will use fats for energy. But, research also shows that HIIT can activate fat metabolism as well.
Here you’ll notice that our cells can convert sugars to fats, but they can’t convert fatty acids into sugars.
Ways For Men to Lose Stomach Fat
For men, the best approach is to combine cardio exercise with progressive weight training, and by this, we mean aim to lift heavier weights, get stronger. Men should focus on large compound moves, such as squats, deadlifts, bench press, shoulder press and rows. You can finish off with some triceps extensions and bicep curls, but don’t spend too much time on these. We have a few workouts you can do, take a look at the classic German volume training and the Full Body Weight Training Workout Split Over 3 Sessions.
When people talk about how to burn fat, they are really talking about building muscle that helps metabolise more fat – so burn fat off with weight training!
The goal is to use your natural testosterone to build more muscle mass, which will help burn more energy and re-balance your hormone levels, to help burn more fat. Fat contains estrogen, and when men gain weight, more estrogen is stored, which can cause all sorts of problems, such as:
- Reduced libido, decreased erectile function – Sexual dysfunction
- Enlarged breasts / man boobs
- Lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH)
- Increased abdominal fat
- Reduction of muscle mass
- Type 2 diabetes
So, building more muscle and burning fat is really good for your health, well-being and general manliness!
Along with the HIIT, you should focus on diet factor, and it really matters a lot. The calories you intake must be proper and if you don’t know much then start managing macros. This is how to lose belly fat fast:
- Download smartphone apps that can help counting calories intake and calories burned on a daily basis.
- Whatever you eat, add into the log. Such apps offer you interactive features to log what you eat and calories burned.
- You can check out carbohydrate, fat, protein and calories with ease. Keep in mind that you eat food with balanced calories.
- The nutrition factor matters a lot so don’t eat readymade food and try to simplify your diet so you can calculate all with ease.
If you start eating veggies, fruit and other foods that provide enough calories and don’t have much fat then you can rely on them. Don’t be a picky eater because it has many harms and lack of nutrition is a major one here.