Body Composition Differ In Runners

How does the Body Composition Differ in Runners?

How Body Composition Impacts Running

Body composition is greatly affected because of running activity. Running and all types of sports themselves change the body composition and shift it towards the pattern of increased muscles and less fat. Exercising, including running, is mainly preferred because it initiates an effective fat loss strategy without much muscle loss and a smart fat reduction system. Furthermore, if runners use the appropriate quantity of nutrients in their diet, they can boost their immunity and augment the rate of recovery from illnesses and any physical traumas.

Body fat percentage

Body fat percentage is a very important component of body composition. It cannot be ignored in any person and especially in athletes. It is usually assumed that sportsmen have ideal body weight, and their body composition would be ideal. However, we might be wrong to assume it directly from their apparent physiques. This is because running too much can destroy their ideal body composition, too, and so taking care of it is crucial.

Body fat and performance

It is important to understand that becoming too thin and slim is not good for the runners’ health. Sports trainers and running experts always promote that every two pounds of reduction in weight increases the speed of running by two seconds per mile. However, they forget that too much fat loss decreases the energy deposits in our bodies. While sprinting or during long-distance running, our body might run out of fuel. This means the body will lack fat reserves, and ultimately, it will start breaking down muscles for glycogen which will be converted into energy.

Fat levels in elite runners

The ideal body fat percentage for elite male runners is 8%, and for elite female runners, it is 12%. Maintaining this level of body fat percentage is important to keep the healthy muscle mass intact. A healthy person usually has a 15% – 20% body fat percentage. Out of this total percentage, 3% of the body fat is essential, which means you would die without it. If the body composition is based on less than the normal amount of body fat percentage, it can cause many negative effects on health. You feel tired and lethargic all the time, making your workouts extremely exhaustive and unenjoyable. The function of your vital organs is diminished, and you might contract infections frequently. This is because your immunity is lowered, and you might feel you have cold or flu-like symptoms all the time. Even your skin might look unhealthy, body pains become a usual thing, and you might feel brain fogged.

The Effects of Running on Body Composition

Running might sound like one of the simplest exercises, just like walking, but it burns a lot more calories than many exercises because of its aerobic nature. It is a cardio exercise and burns as much as 11.4 calories per minute in a person having 120 pounds of weight. The bone width in marathon runners is ideally more in size than a sedentary person. This has been proven in a scientific study published in Science Direct. It shows that running plays a major role in decreasing the rate of body composition changes one experiences because of the natural aging process. This prevents the loss of muscles and bones as age increases and keeps the body composition near ideal for a longer period of life.


Metabolism is the measure and rate of provision of calories through the amount of food we consume daily. The food intake is broken down into simpler molecules to provide energy to our body for the normal functioning of body processes. People who aim to lose weight sometimes blame their body metabolism. Commonly, a higher metabolic rate makes weight loss attempts easier and quicker. So, no doubt, if you increase your metabolic rate, you will burn more calories in a shorter period and with fewer intensity exercises.

Whatever you eat and drink, and the level of the basal metabolic rate of your body decides your body weight. The determination of body weight can thus be controlled by the amount of food you eat and the duration and intensity of your physical activities. Metabolism thus plays a very important role in body composition and, most importantly, the body fat percentage. There are hundreds and thousands of processes and functions conducted by millions and trillions of cells in your body during rest. As a result, you are burning calories and using your energy at that time.

Metabolism and Running

The main question that arises here is that although every person has the same type and degree of processes in the body, why does the metabolic rate differ in every person? This is because the level of the metabolic rate required is unique to every person, and there are a lot of factors that affect it. For example, your hormonal balance, genetic features, environmental factors, age, and even disease conditions might speed or slow down your metabolism.

Running does not boost your metabolism all day, but studies have shown that running is a great way to fasten your metabolic rate. If your goal is to increase your metabolic rate, professional experts recommend doing moderate to high-intensity cardio exercise (running) for almost 150 minutes to 300 minutes per week.

Does running cause muscle loss?

This sounds lame because we think that running increases muscle mass. This is a very general impression of exercising. However, this might not be true in all cases. Fat loss and muscle gain or vice versa is a game of balance and ratio of body components. High-intensity exercise with a short duration is ideal for protecting muscular health and increasing lean body mass. Sprinters have strong leg muscles because they run fast (high intensity) with a shorter duration. For long-distance runners, the duration is longer, and the muscles do not have an intense workout because the speed varies from slow to moderate. So long-distance runners have more chances of muscular damage and loss. Furthermore, as already mentioned above, if you lose too much fat, you finally start losing muscles for energy. So the balance of diet and exercise is important in this case.

Does running burn fat?

The only direct source of energy to the body is the consumption of carbohydrates. However, our body makes droplets of fat molecules from the lipid diet we consume for long-term energy conservation. These fat droplets are then made into fat reserves deposited underneath the skin. When a sportsperson does running or sprinting, the direct energy source quickly depletes, and the body starts relying on the fat stored in the adipose tissue. The fat gets broken down to give the energy needed for running.

At what intensity do I need to run to burn fat?

When you run with high intensity, you burn calories, not necessarily from fat. When we do light jogging, light running, or simply walking, the body gets oxygen easily and uses it to burn fat. However, when you do sprint, the body does not get enough oxygen because you cannot breathe at the required pace. This makes the body shift again towards utilizing carbohydrates for energy. So the perfect way is to do light intensity running. A slow, low-intensity running will burn your body fat more effectively. It will take longer to burn more calories, but the optimum amount of fat will be burnt this way. The recommended time for this type of running is usually longer than 30 minutes.

How does jogging change your body composition?

Jogging and running are cardio exercises that positively change your body composition. Jogging burns your calories in such a way that melts down your fat and maintains and increases your lean body mass. This is because the food we eat gets converted into fat and is stored in our bodies. Therefore, if we keep running or jogging as a regular workout, we can burn down that fat and maintain the body composition to near ideal. Although jogging is an efficient way to burn calories, it needs a combination to burn the actual fat. This can be done by pairing your jogging and running with a diet plan lacking in fat so that you can burn more calories than consume them.

How sprinting affects your body composition

Sprinting is a sport that involves all your muscles to reach the target by running at the maximum speed possible. Sprinting is incorporated in the training sessions of almost all sports professionals because it exercises all the body muscles, i.e., your thighs, butts, chest, abdomen, and pelvic. Sprinting is a great way to build up your body muscles and burn down fat. It is a certain way to build muscles but running or jogging is often preferred over sprinting if the target is weight loss by burning fat.

How to Increase Body Composition Changes

Track Your Heart Rate

People with normal weight and normal body composition usually have slower heart rates. Obesity and overweight lead to a slight increase in the heart rate. Sprinting, running, and jogging are the best ways to improve your body composition, which will ultimately make your heart rate slower too. With the changes in body composition, it is always advised to regularly track your heart rate. This can be done by heart rate measuring devices and through a 3D body scanner called Visbody. It not only gives you your complete body composition analysis but also measures basic health parameters like heart rate.

Eat the Right Foods (And the Right Amount)

Eating the right nutrients for a diet is very important to improve body composition and reduce body fat percentage. Including the optimum amount of proteins in your food builds muscles, especially for runners. The amount of protein to be taken is determined by the total calories consumed through diet. The total number of calories is multiplied by 0..75 as a factor in the number of proteins in grams that should be consumed per day.

Run Harder, Longer, and More Often

The harder you run, the more intensity you add to your exercise. The longer you run, the more time you give to your exercise. Adding regularity to running is the key to getting positive results on your body. You can burn the highest number of calories by running harder, longer, and consistently. This will help you reach the ideal body composition much faster.

Measuring Body Composition

Measuring body composition and body fat scales is crucial for the health and training of individuals involved in running and sprinting. The body fat percentage must be within the recommended limits to maintain the best physique and physical health. Bioelectrical Impedance Analysis is considered the most reliable method to measure body composition.


Ideal health is essential for the performance of sprinters and runners. Body composition determines the physical health of the runner, and it must not be ignored. The recommended ratio of fat to muscles should be adequate, and the burning of fat should be achieved by low intensity and long-running duration.


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