Puberty – the period of life in which a runner is formed
Puberty marks the last period of intensive growth and development in children, in which there is increased secretion of growth hormone and sex hormones. Girls enter puberty as early as 11, while boys do so a year or two later. Most of the changes experienced in puberty are genetically predetermined, but it is important to know that every child develops at their own pace, so it is important to stress the difference between chronological and biological age.
For girls this period is the moment of the fastest and best progress, and if they do not continue training, they will never again in their lives achieve adequate results. The advantage of boys over girls is the anatomical size of the lungs and a higher concentration of red blood cells and haemoglobin in the blood, so boys can deliver a larger amount of the oxygen needed for muscle work. Maximum pulse decreases over time, by one to two beats a year, and at the end of biological development men are 10–12 cm taller than women, 8 kg heavier and have a higher percentage of muscle and a lower percentage of fat. As a result, men have on average 20% greater aerobic capacity and 25% greater relative strength. Biological development is completed at the age of 25.
Height is as much as 98 percent genetically predetermined. During puberty one can grow as much as 10 cm in a year, and in some cases height increases by 30 cm, while body weight is not as genetically predetermined as height and depends above all on lifestyle, diet and training. In puberty girls and boys gain 7 to 10 kg. Puberty marks the beginning of organised training for the development of endurance, but training must still retain its all-round character, so besides running it must include activities such as swimming, cycling, hiking, rowing, etc. Long-duration running requires extended training time, which can turn children away from other social activities that are extremely important for the overall development of an adolescent.
When it comes to the intensity, or rather duration, of training, it can be increased from 45 minutes to 60, then 75, and up to 90 minutes of intensive physical activity. The number of sessions should increase from 3 to 4 and up to 5 a week; the length of exercises should be increased gradually, the breaks between intervals shortened and more complex tasks set. Excessive and prolonged running on hard surfaces can cause damage to both muscles and joints. The skeletal system develops faster than the muscular system, which often leads to sports injuries if training is not properly dosed. When proper running technique breaks down, the interval should be stopped until full recovery and only then continued. In this period children are still not ready to enter a session insufficiently recovered from the previous one, and this also applies to runs within the session itself. It is important to know that training does not start with an exercise until the children have fully recovered from the previous exercise.
Besides work on developing endurance, this period is also good for developing strength and joint mobility. Strength should be developed primarily with exercises in which the resistance to be overcome is one’s own body, while stretching exercises should be done at the end of every session to maintain muscle elasticity into adulthood. With age, elasticity declines if one does not exercise.
These are the guidelines for the proper development of future runners:
– make training interesting by changing the length of the run, the surface, the way of running…
– include in training tasks that will slowly awaken awareness of long-distance running tactics, and work on automating the technique adopted during pre-puberty
– stress the importance of fair play
– develop the habit in children of drinking water often during training
– include them in the competition system
– provide time during training for socialising and play
– inform children about autogenic training and visualisation techniques
– organise competitions during training, but without putting the emphasis on speed