Elite runners’ body fat usually ranges from 5 to 11 percent for men and 10 to 15 percent for women. This is because long-distance running tends to use fat stores for fuel.
However, being underweight means having a body mass index (BMI) below 18.5, which may not necessarily be true for all marathon runners.
But do you need to be skinny to run a marathon? Read on to find out.
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What is Underweight For a Marathon Runner?
As a runner, I understand the importance of maintaining a healthy weight to optimize performance. But what exactly does it mean to be underweight?
According to medical standards, a person is considered underweight when their Body Mass Index (BMI) is below 18.5.
Body Mass Index (BMI)
BMI is a measure of body fat based on height and weight. It is calculated by dividing weight in kilograms by height in meters squared. While BMI is not a perfect measure of health, it is a valuable tool to assess if someone is underweight, overweight, or at a healthy weight.
For example, a 5’8″ and weighs 115 pounds would have a BMI of 17.5, considered underweight. In contrast, a person who is 5’8″ and weighs 160 pounds would have a BMI of 24.3, which is regarded as a healthy weight.
Why Underweight is a Concern
Being underweight can have negative health consequences, including:
- Increased risk of infections and illness
- Decreased muscle mass and strength
- Decreased bone density and increased risk of fractures
- Decreased fertility and menstrual irregularities
- Decreased energy levels and fatigue
As a runner, maintaining a healthy weight is vital for optimal performance.
However, it is essential to do so safely and sustainably. For example, extreme dieting or over-exercising to achieve a low weight can harm physical and mental health.
Marathon Runners and Weight
Body Composition of Marathon Runners
As a marathon runner, I can attest that we come in all shapes and sizes.
However, there is a common misconception that marathon runners are underweight. While it is true that many elite marathon runners have a low body mass index (BMI), this is not necessarily the case for all runners.
According to an article in Runner’s World, a lower BMI is essential for longer race distances, but the optimal BMI can vary depending on the runner’s gender and race distance.
For example, the optimal BMI for male 800m runners is between 20 and 21, but it drops to 18.5 and 19.5 for male marathon runners. In general, marathon runners tend to have a lower percentage of body fat and a higher percentage of muscle mass.
This is because running burns many calories and helps build lean muscle. However, this does not necessarily mean that marathon runners are underweight or unhealthy.
Factors that Affect Weight in Marathon Runners
Several factors can affect a marathon runner’s weight.
One of the most obvious is training volume. For example, runners typically increase their mileage significantly when training for a marathon, which can lead to weight loss.
However, this is only sometimes the case, as some runners may compensate for the increased calorie burn by eating more.
Another factor that can affect weight is diet. Many marathon runners follow a strict diet to optimize their performance, including limiting processed foods and increasing their intake of fruits, vegetables, and lean protein.
However, some runners may need more support to maintain a healthy weight if they become too restrictive with their diet.
Finally, hormonal fluctuations can also affect weight changes for marathon runners. Women, in particular, may experience weight gain or loss due to changes in estrogen levels throughout their menstrual cycle.
In conclusion, while it is true that many elite marathon runners have a low BMI, this is only sometimes the case for all runners.
Marathon runners tend to have a lower percentage of body fat and a higher percentage of muscle mass, but this does not necessarily mean that they are underweight or unhealthy.
Factors such as training volume, diet, and hormonal fluctuations can all affect a runner’s weight, and each runner needs to find a healthy weight that works for them.
The Debate on Underweight Marathon Runners
Arguments in Favor of Underweight Marathon Runners
As a marathon runner, I have often heard that being underweight can be advantageous when running long distances.
One of the main reasons for this argument is that carrying less weight can make running more accessible and less taxing on the body.
Additionally, being underweight can result in a lower body fat percentage, often associated with better running performance.
This is because having less body fat means the body can more efficiently use stored energy during a run, leading to better endurance and faster times.
Furthermore, elite marathon runners are often lean and light because they spend hours a day training for their endurance.
In training, they burn up all their calories, resulting in a deficient body fat percentage and lean muscle mass. This allows them to run faster and more efficiently during a marathon.
Arguments Against Underweight Marathon Runners
On the other hand, there are many arguments against the idea of underweight marathon runners.
One of the main concerns is that being underweight can lead to health problems such as weakened immune systems, decreased bone density, and increased risk of injury.
Another concern is that underweight runners may need to properly fuel their bodies, leading to decreased energy levels and performance. Insufficient fuelling and refueling, pre and post-run, can also lead to weight loss, which can be detrimental to performance and health.
Finally, it’s essential to recognize that losing weight will not guarantee success in marathon running.
While having a lower body fat percentage can be advantageous, it’s essential to maintain a healthy weight and body fat percentage to avoid health problems and injury.
The Risks of Being Underweight
Health Risks of Being Underweight
Maintaining a healthy weight is essential for optimal performance as a marathon runner. However, being underweight can pose significant health risks.
According to Medical News Today, underweight individuals may experience low blood counts, known as anemia, which can cause dizziness, headaches, and fatigue.
Underweight women may also experience irregular periods. Additionally, low body weight can lead to weakened immune systems, making individuals more susceptible to infections and illnesses.
In extreme cases, being underweight can lead to malnutrition, which can cause a range of health problems, including organ damage, weakened bones, and even death.
Maintaining a healthy weight and consuming enough nutrients to support your body’s needs is essential.
Performance Risks of Being Underweight
While maintaining a low body weight is often associated with better running performance, being underweight can have the opposite effect.
According to Runner’s World, low bone density can lead to stress fractures during training and an increased risk of fractures later in life.
Additionally, insufficient fueling and refueling before and after runs can lead to weight loss and decreased performance. It is essential to recognize that losing weight will not guarantee success and may lead to health problems.
As a marathon runner, it is essential to maintain a healthy weight and ensure that you are consuming enough calories to support your training and growth. In conclusion, being underweight can pose significant health and performance risks for marathon runners.
Maintaining a healthy weight and consuming enough nutrients to support your body’s needs is essential.
Final Thoughts
In conclusion, marathon runners tend to have a leaner physique than other athletes, but not all marathon runners are underweight. The body type of marathon runners mainly depends on their training and diet.
Marathon runners need to consume enough calories to fuel their bodies during long runs, but they must also be careful not to overeat and gain weight.
It is important to note that while being underweight may provide some advantages in distance running, such as less weight to carry during a race, it can also lead to health problems. Skinny runners may be more prone to injuries and illnesses due to a weakened immune system.
Therefore, marathon runners must find a healthy balance between training, diet, and body weight.
This can be achieved through proper nutrition, hydration, and strength training to build and maintain muscle mass.
