Exercise Recommendations and Responses in Children

Exercise refers to bodily movement aimed at maintaining or improving parameters of fitness often in the pursuit of optimal health and well-being. For children ages 6 to 17, the US Department of Health and Human Services recommends 60 minutes of moderate to vigorous exercise daily that is comprised of aerobic activity, muscle strengthening activity, and activities that can result in bone-strengthening.  

Children enjoy the many benefits of exercise including optimal body composition, a strong muscular skeletal system, a healthy cardiovascular system, and improved cognition; however, they do not have the same exercise responses throughout their childhood or when compared with adults. Exercise physiologists broadly view childhood growth and maturation in two groups, up to age 12 and from 13 to 20. With the advent of puberty, hormonal changes have a profound effect on exercise physiology and performance in the postpubescent child.  

Prepubescent children have smaller hearts that pump less blood per beat than an adults’ and their respiration is shallower with a higher respiration rate and maximum heart rate. Children move less economically resulting in a higher energy cost and oxygen requirement during aerobic activity.  They also produce more heat relative to body mass than adults and release less sweat per gland and have a lower sweating capacity—with sweating known as an important way to cool the body. These and other differences result in prepubescent children having shorter exercise tolerance time and longer periods of acclimatization when exercising in a new climate.

With all of this in mind, it is important to respond to a prepubescent child’s expressions of fatigue or heat tolerance at any point in their movement activity. They are likely to intuitively and proprioceptively respond to their need to slow down or rest, as well as hydrate. When children are exercising in a mode that is also fun, they most certainly would rather continue than stop, but will eventually experience and hopefully express their need to rest, refuel, and rehydrate. Children should be afforded an adequate opportunity to drink fluids before, during and after exercising. Fluid intake should be approximately 13ml per kilogram of body weight per hour or 6ml per pound of body weight per hour.

In terms of muscular strengthening activities, prepubescent children can safely participate in submaximal muscular exercises beginning with their body weight and gravity as a means of overload. Examples to this end might include activities that can be safely pursued on a jungle gym or modified push ups and abdominal exercises. Strength gains in prepubescent children may result from improvements in the neuromuscular system and increased motor unit recruitment rather than hypertrophy that results from growth in the cross-sectional area of muscle fibers.  Prepubescent children can progress to light resistance muscular strengthening activities with proper supervision for movement form and appropriate overload. Much research has demonstrated that submaximal muscular strengthening activities do not pose a threat to growth plates—it is always best to check with your pediatrician before beginning any new exercise programming for your child. Both aerobic activity and muscular strengthening activities have a positive effect on bone health.

As leaders of children, we must remember that physiologically they are knee deep in the processes of growth and maturation with important refueling, rehydrating, and rest requirements to achieve optimal health and well-being. Exercise and movement are integral to their overall growth and development, but they are not miniature adults, nor should they be treated as such. The good news is that children who regularly exercise throughout their childhood are more likely to continue into their adulthood reducing the incidence of lifestyle-related diseases. It is our job to ensure their exercise and movement bouts result in positive, uplifting, and achievable experiences that inform their health and well-being choices throughout their lifetime.