Not all young athletes manage to eat enough

Growing adolescents who train heavily often do not understand how much food they need. The consequence can be injury.

This is explained by clinical nutritionist Anu Koivisto-Mørk at the Sports Health Centre (Idrettens helsesenter). She has written her PhD thesis at the Faculty of Medicine at the University of Oslo on diet and nutrition in sports, with a particular focus on altitude training.

Koivisto-Mørk explains that she meets young athletes in her office who want to do everything for their sport and have high ambitions.

Many of them are football players, which is one of the sports where injury frequency is particularly high.

Some of these athletes misunderstand what it means to eat correctly and are excessively concerned with what is healthy. Some of them actually eat too healthily, she believes.

Young athletes. — According to the nutritionist, it is not uncommon for young athletes to choose foods that contain little energy in relation to total volume. Photo: Colourbox

Organised sport is highly popular among Norwegian youth and forms a vital part of most young people's lives. According to Ungdata.no, 74 per cent have been members of a sports club since starting lower secondary school, and 92 per cent have participated in organised sports since childhood.

Many train actively to achieve high ambitions of a sports career, and football is especially popular.

What does it mean to eat "too healthily"?

According to the nutritionist, it is not uncommon for young athletes to choose foods that contain very little energy relative to their volume. Many are focused on ensuring there is minimal sugar, that the food is low-fat, and that it is "clean food" — meaning as little ultra-processed food as possible, Koivisto-Mørk summarises.

In such cases, there is a risk that the food they eat is very filling, yet their bodies still receive too little energy during a vulnerable phase of development. Context and activity are crucial in determining how much energy we burn in our daily lives. Ambitious young athletes who train heavily and are still growing require a significant amount of extra energy.

Koivisto-Mørk believes that the extra energy found in, for example, desserts, Saturday sweets, and baked goods can be eaten with advantage when training heavily.

She is supported by Håvard Moksnes, a sports physiotherapist at the Sports Health Centre, who is attached to the medical support team for the women’s national football team. He also holds a PhD in knee injuries in children.

Losing the sense of hunger

One might assume that young people who train and become very hungry would devour large amounts of food to make up for the energy they use in their sport. And indeed, many do.

NRK sports commentator Andrine Hegerberg has prievious told about how she and her sister ate everything they could get their hands on when they were young football players. They would often eat cinnamon buns (kanelgifler) to ensure they met their energy needs.

From the top series, Lyn - Brann in 2023. Andrine Hegerberg then played for Brann at the Grorud arena. Photo: Alf Simensen/NTB.

However, the vast majority of athletes who struggle with energy deficiency do not deliberately restrict their food intake. They simply do not know how much they need in relation to how much they train, Moksnes explains.

We also know that very intense and hard training can negatively affect appetite, Koivisto-Mørk says. According to the Norwegian Health Informatics website, intense training sessions can suppress levels of the hunger hormone ghrelin.

We often have to tell athletes that they must remember to eat even if they do not feel hungry. It is essential to establish good routines for regular food intake.

Ask what they are eating!

A good place to start for parents and coaches who are concerned about an athlete is to ask: "What did you have for breakfast today?" Because the answer is often "I don't eat breakfast," Moksnes says.

If the athlete replies, "I had porridge with lots of toppings," that is excellent — that is the kind of porridge many of our young athletes eat now, he explains.

Håvard Moksnes og Anu Koivisto-Mørk. Photo: UiO.

Follow up by asking what the athlete ate for their evening meal, and the conversation is underway. Moksnes says that he asks his own patients these questions. If the answers cause concern, he refers them to a clinical nutritionist.

A good diet prevents injury

According to Skadefri.no, food intake must cover the energy required for all the processes occurring in the body, independent of training and activity. This is known as the resting metabolic rate. In addition, food must cover energy for all everyday activities, as well as training and competitions.

Several thousand children and young people in Norway suffer from sports injuries annually. The most common injuries are bone fractures, injuries to growth zones, and overuse injuries.

Stress fractures affect an estimated eight per cent of young female football players. Football tops the statistics due to the high number of active participants, followed by basketball, handball, and sports that require a lot of jumping and physical contact.

As competition in sports becomes more significant, both training intensity and training volume increase for many young athletes. According to Olympiatoppen.no, approximately 3 to 11 per cent of school children are injured every year in sports.

Research from the Oslo Sports Trauma Research Centre (Senter for idrettsskadeforskning) shows that half of all sports injuries can be prevented with simple measures such as strength, balance, and joint-control training.

Andrine Hegerberg in the weight room with players from BK Håcken's women's team in 2022. Photo: Anders Deros, Aftonbladet/NTB.

Proper recovery is also absolutely essential to benefit from training and is crucial for preventing overuse and injury. A good and varied diet is a vital part of this — even when you are injured and sitting on "the bench".

It is during the recovery phase that the body rebuilds itself after training. Good recovery is about eating enough, drinking enough, and getting enough rest and sleep, Moksnes says.

When the body is injured, it needs nutrients and energy — often more than most people think — to heal and avoid unnecessary loss of muscle mass, Koivisto-Mørk adds. If you do not eat enough, healing will be delayed, and the rehabilitation period will be prolonged.

Are you worried about REDs?

REDs is an abbreviation for 'Relative Energy Deficiency in Sport', and describes a syndrome that occurs when the body, over time, receives too little energy relative to its needs. This is caused by an imbalance between training, daily activities, and food intake.

Training can steal so much of the total daily energy intake that too little is left for the body's normal functions, as well as growth and development.

Snacks, sweets and baked goods are often necessary to get sufficient energy intake when you are a young athlete, says Anu Koivisto-Mørk. Photo: Colourbox.

REDs can affect both boys and girls who participate in sports — especially those who train heavily. Adolescents undergoing rapid growth can also be at risk. Symptoms can include fatigue, decreased performance, repeated injuries and stress fractures, menstrual disturbances in girls, lack of morning erections in boys, and delayed growth and development in young people.

Poorer benefit from altitude training?

Research suggests that athletes with REDs may also derive less benefit from altitude training. In addition to sufficient energy, the body also needs protection from antioxidant-rich foods, Koivisto-Mørk says. In her 2023 doctoral thesis, she investigated, among other things, whether an increased intake of antioxidant-rich food, served as mid-meal snacks, affected physiological adaptations, as well as inflammation and oxidative stress in adult elite endurance athletes training at altitude.

The results from the clinical study showed, among other things, that doubling the daily intake of antioxidant-rich foods during a training camp at moderate altitude increased the body's capacity to absorb antioxidants. It also dampened some of the inflammation that the body can develop during altitude training.

A daily intake of smoothies, dried fruit, berries, nuts, and dark chocolate increased blood antioxidant levels and contributed to a better composition of nutrients in the diet. However, it did not reduce oxidative stress.

Her research highlights that energy- and nutrient-dense mid-meal snacks are smart during altitude training.

Eat enough and aim to "eat a rainbow" every day. Ensure you get plenty of colours throughout your training day, even when training at altitude, and preferably in concentrated form so you do not become full too quickly.