Are kids' sports putting their hearts in danger?

Regular exercise is typically lauded as a cornerstone to better heart health, but for many youngsters and young athletes, training goes much beyond the usual advice for everyday activity.

Young athletes can log over 10 hours of physical practice in a single week, which is significantly above the one-hour target that the World Health Organization recommends for children and adolescents.

Concerns are rising over whether the intensity of some exercises can place immature hearts and blood vessels under too much stress.

In a new study called the Munich Cardiovascular Adaptations in Young Athletes Study (MuCAYAplus), researchers want to define where beneficial exercise crosses the line and becomes potentially hazardous.

This initiative is supervised by Prof. Renate Oberhoffer-Fritz from the Institute of Preventive Pediatrics at the Technical University of Munich.

By analyzing training and health markers over three years, the team intends to identify how severe weekly activity levels could modify the cardiovascular system in children as young as 10.

Why exercise is important for young hearts

Physical activity in children can promote heart health, weight control, and lessen the risk of numerous illnesses, including obesity and diabetes.

Some research suggests that moderate training creates a stronger heart, as this organ is known to adapt over time by extending its chambers and occasionally thickening its walls.

Young athletes often exhibit improvements in endurance and oxygen use, which may lessen illness risks in maturity.

When training intensity becomes an issue

Even though most athletic activities are safe, difficulties might emerge when youngsters train more regularly than recommended.

A handful of studies suggest that putting young athletes through very long or intensive training sessions could contribute to worrying changes in the heart’s size and function.

In certain situations, these alterations might lead to an elevated risk of illnesses like hypertrophic cardiomyopathy.

Some data also imply that excessive exercise is associated with the hardening of blood vessels and detrimental oxidative stress; however, these findings are not totally consistent across all age groups.

What MuCAYAplus attempts to learn

Rather than focusing exclusively on heart rate or strength, the MuCAYAplus team is gathering a broad variety of measures.

These include electrocardiograms, blood pressure checks, ultrasound scans of the heart and carotid artery, blood sampling, and full fitness testing on a bicycle ergometer.

By taking annual “snapshots” of each subject in this way, investigators hope to know exactly how heart muscle thickness, blood vessel flexibility, and biochemical variables evolve over time.

They are also examining how thyroid hormones, leptin, and antioxidant enzymes might influence into heart health for developing kids.

Nutrition and the young heart

Feeding habits could play a factor in how the body copes with hard activity. While some hormones like leptin help control hunger and modulate blood vessel tone, low calorie intake might disturb the thyroid hormones that influence growth and heart development.

By tracking the diets of young athletes through a questionnaire, the research group hopes to find out if high training loads, along with insufficient fueling, heighten the risk of detrimental changes in blood pressure or heart muscle size.

Implications for coaches and parents

Coaches often urge young athletes to test boundaries, especially when a child shows promise. However, defining the safe level for training is crucial.

If the MuCAYAplus experiment proves that high levels of activity contribute to negative cardiovascular adaptations, families might need to change schedules or diversify sports to minimize persistent stresses on the heart.

On the other hand, they may identify particular markers – like enhanced vascular elasticity and antioxidant levels – that highlight good reactions to balanced workouts.

Looking ahead

Early data from smaller projects have revealed that children can withstand a wide range of activity levels, providing they have the correct instruction, rest, and nutrition.

The MuCAYAplus study’s unique, three-year timeframe offers a chance to evaluate how a developing cardiovascular system adapts across growth spurts.

Its data may eventually help scientists design sport-specific guidelines that take into account a child’s age, developmental stage, and weekly exercise intensity.