The adolescent years are some of the best years to be taking advantage of the changes taking place in the body and apply them to fitness and overall health. This is part one on a new series that we’ll be covering on aging and the human lifespan and how it relates to fitness with health. We’re going to be starting with adolescents and then going decade by decade to take a look at how aging can effect a body and how you can help better prepare yourself to get the most out of your body and your workouts.

Fitness In Adolescents

We all can’t be spring chickens forever. There’s no greater time to focus on fitness than when in the age of adolescence. The age of adolescence is roughly from age eleven to around twenty one and marked by the onset of puberty. The onset of puberty generally happens to women first – around the ages of eight to thirteen. For males, the general onset is a few years behind women starting at around ages ten to fourteen. By mid-adolescents, ages fourteen to sixteen, men and women are generally equal before things finally come to a close in early adulthood around age twenty-one. Keep in mind, every individual is different, some people may start their transition into adulthood earlier or later than others. We’re all aware of the changes that take place, but how does all of this pertain in developing fitness in adolescents?

Hormonal Contributors That Relate To Fitness In Adolescents

The onset of puberty is marked by massive releases of hormones within the body. One of the key players that are responsible for the onset of growth are thyroid hormones. These hormones are responsible for effecting bone growth, metabolic rates, and overall metabolism. At the same time a couple of other major hormones are being secreted in mass concentrations: testosterone in males and estrogen in females with additional androgens in females (growth hormones) being secreted by the adrenal glands which sit on top of the kidneys. All of these hormones help with growth and metabolism and can have effects on fitness during the adolescent years.

Fitness In Early Adolescents

Early adolescents is marked by around ages ten (the onset of puberty) to fourteen. While physiological changes generally happen earlier in females than they do males, the net result eventually ends up being the same: transition into adulthood. This time is marked by rapid growth spurts.

Bone Growth

The bones of the hands and feed generally grow first, followed by the torso, then legs and arms. Around age 8, girls start to add more fat to their arms, legs, and trunk, that continues to around age 11-16. In males, arm, and leg fat generally decrease in boys.

Muscle Growth

With the growth in bone size comes the next big thing: growth in muscles to support the bones. Muscles grow larger in both females and males but, adolescent males go on to develop larger skeletal muscles, bigger hearts, and with a bigger torso, lung capacity increases. In boys, the number of red blood cells increases.

What All Of This Means

Coming out of childhood and going into adolescence obviously means that there are going to be limitations physically as to what the body is capable of. Because thyroid hormones aren’t as potent, children have a more difficult time regulating body temperatures than adults. As a result, hot temperatures and ares with higher humidity need to be taken into consideration. With smaller lungs and hearts and less blood cells, intense anaerobic exercise exceeding longer than ten seconds isn’t tolerated too well without providing sufficient rest and recovery between training repetitions. It’s recommended that the intensity progression of training should only increase about ten percent each week for aerobic sports such as soccer, basketball, football, etc.

As growth spurts continue and has metabolic regulating hormones continue to become more efficient into the later years of early adolescents, young teens will become better at tolerating exercise and the intensity of exercise. Children going into puberty also have more difficulty regulating their blood sugars through glycolytic enzymes. As they progress through puberty, the body becomes more efficient at reglulating energy requirements.

Fitness Recommendations In Early Adolescents:

-As mentioned, they have a more difficult time performing longer-duration high intensity drills.
-Recommended resistance exercise: 1-2 sets of 8-10 exercises consisting of 8-12 reps per exercise.
-For strength development, bones and muscles begin going through an increased phase of growth; strength exercise is recommended at six to eight reps per set for strength.
-For muscular endurance weight training, reps shouldn’t exceed more than twenty reps.
-Early adolescence is a time to take advantage of neurological development. Any exercise that helps to develop muscle awareness and balance as well as agility helps neurons grow to become more efficient at movements and helps to develop skil.

Fitness In Middle Adolescence

Middle adolescence is generally marked between the ages of fourteen to sixteen. During this time, most of the changes that occur in early puberty begin to slow down and wrap up. Generally speaking, growth changes don’t happen at such a rapid pace as they do in early adolescence but some things still continue until late adolescence.

What All Of This Means

The last half of adolescents is one of the best times to be involved in fitness. The body is a wonderful machine at adapting to physical stressors. As the lungs grow, heart grows bigger, and red blood cells multiply in number, the body becomes more and more efficient at tolerating exercises. Since muscles are young (and so are joints), this is also one of the best times to take advantage of flexibility. As most adults are aware, flexibility can be an issue that plagues them when it comes to certain exercises such as running, squats, or other many exercises. This is one of the best times to take advantage of making sure joints are lose and flexibility is at an optimum.

Fitness also generally helps to establish neurological connections. These connections allow the body to be more aware and can help with athletic performance and life in general. This is one reason why it’s easier to learn something as a teen (whether it be athletic performance or say, the guitar) than it is a person who is their forties.

Fitness In Late Adolescents

Late adolescents is marked with the ages of sixteen to twenty-one to twenty four. Late adolescents is characterized by the time period where a person achieves their adult appearance. Growth spurts for both sexes usually wrap up during this period as hormonal secretion slows. Bone growth in the long bones (arms, legs) wrap up during this time but can continue into the early twenties for some people. Muscle growth also occurs to accommodate the the larger skeletal structure.

In addition to the musculoskeletal changes, there’s also a lot happening neurologically. Stimulated nerves within the body get stronger. Those nerves that have decreased stimulation go through a period of “pruning.” This can have important implications for fitness.

What All Of This Means

As a person approaches late-adolescence, the framework that goes into building an adult body is nearly in place, although some bones may not be finished growing, late adolescence is a time that one can resume a routine that can handle the stressors that an adult workout entails.

Nutritional Requirements During Adolescents

Aside from physical factors taking place during adolescence, it’s also one of the most important times to take advantage of nutrition. Unfortunately, the teenage years are often marked by diets on the go and infrequent eating. Teens are the most likely group to skip breakfast, eat empty calories, and eat on the run. With the increase in bone growth and increase in metabolism, vitamin and mineral requirements should be met. Iron requirements in females increase as they begin having menarche, they are more at risk for anemia. Calcium, vitamin A, D, and C can help support bone growth and vitamin B can help support healthy a healthy metabolism and blood cell growth.

Summing Up Fitness In Adolescents

-Early adolescence is marked by a period of rapid growth and boost in metabolism; the body isn’t as efficient as an adult body at oxygen usage and workouts need to be scaled down to allow for greater rest periods for explosive activity.

-As adolescence continues the body becomes more efficient at temperature regulation, metabolism, and oxygen usage (lungs expand, heart grows bigger, the body has more red blood cells). Bones and muscles continue to grow larger and can support more weight training and higher intensities of cardiovascular exercise.

-Middle to Late adolescence is one of the best times to take advantage of building a framework for adulthood – resistance exercise and weight training helps promote a healthy cardiovascular system as well as help build dense bones.

-Adolescence is one of the best times to take advantage on building agility and taking advantage of flexibility (flexibility only decreases with age). Building agility helps promote nerve awareness/development as the least used nerves go through a period of “pruning” towards the end of adolescence. It’s one of the best ages to learn and develop skills.

-Fitness should be fun and something enjoyable.

-Nutritional needs (as with any phase in life) need to be met.

-Overall, traditional weight training should progress after proper technique is learned. Coming out of childhood and going into adolescence, skill, agility, and developing balance are an important skill set that need to be taken advantage of.

Questions about working out or fitness in an adolescent? Let us know.

Our next topic will discuss fitness and age related factors that take place during the twenties.


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