Future force readiness at risk: Pediatric Inactivity Triad

The global decrease in children’s physical activity has led to more than an increase in childhood obesity; it has led to a less-prepared group of applicants for military service. Nearly 75% of the military's recruiting pool in the United States (ages 17 to 24), are considered ineligible for service, often because they’re overweight or  unfit. Three factors likely contribute to this obesity among potential recruits: exercise-deficit disorder, pediatric dynapenia, and physical illiteracy. Some researchers call this combination the “Pediatric Inactivity Triad” (PIT).

  • Exercise-deficit disorder describes what happens when people don’t get the recommended minimum 60 minutes of physical activity a day. In the case of today’s youth, it often means they’re not taking part in recess or gym class at school, or playing outside at home. But instead of just calling it “inactivity” or saying kids don’t play enough, researchers now label it as a disorder to highlight how serious the issue can be.
  • Pediatric dynapenia, or low levels of muscular strength and power, is the second part of PIT. Normal play activities such as running, jumping, and climbing take a certain amount of strength, which can be slow to develop if kids don’t engage in those activities. When children avoid play because they lack the basic abilities that often come from active play, a cycle occurs that can be tough to break: Not enough play leads to low muscular strength, which makes playing more difficult, which can discourage future play.
  • Physical illiteracy describes a lack of confidence, ability, motivation, and knowledge to move well. Remember how discouraging it could be to not be able to throw a ball as far, dance as well, or run as fast as some of the other kids? This discouragement makes it tempting to avoid those activities, contributing even more to the cycle of not getting enough activity and low levels of muscular strength.

These conditions combine to create a difficult nut to crack in the fight against childhood—and future adult—inactivity, obesity, and related health problems. The best way to attack the Pediatric Inactivity Triad is to find and address the barriers that limit a child’s motivation to play.

If you have kids in your life who might fall into the Pediatric Inactivity Triad, find out what’s stopping them from playing. Is it a lack of space, such as not having a yard or nearby playground? Do friends live too far away for daily playdates? Is the child or teen a bookworm or gamer who’d rather spend the day inside than outside throwing a ball?

The implications for obesity and pediatric inactivity are far reaching, but small changes can lead to lifelong rewards. Once you identify some of the barriers to exercise that lead to pediatric inactivity, you can create a culture that promotes physical activity, whether it’s a daily walk, regular visits to the park, or other activities. For suggestions on how to get your kids more active, read HPRC’s Increase your child’s play time…and health and Put some fun in your children’s fitness.


Faigenbaum, A. D., Rebullido, T. R., & MacDonald, J. P. (2018). Pediatric Inactivity Triad. Current Sports Medicine Reports, 17(2), 45–47. doi:10.1249/jsr.0000000000000450

Recruiting, Retention and End Strength, Hearing before the Military Personnel Subcommittee of the Committee on Armed Services, House, 111th Cong. 4–5 (2009) (testimony of Dr. Curtis Gilroy). https://www.gpo.gov/fdsys/pkg/CHRG-111hhrg50088/pdf/CHRG-111hhrg50088.pdf

Stracciolini, A., Myer, G. D., & Faigenbaum, A. D. (2015). Exercise-Deficit Disorder in children: Are we ready to make this diagnosis? Physician and Sportsmedicine, 41(1), 94–101. doi:10.3810/psm.2013.02.2003

Tremblay, M. S., Barnes, J. D., González, S. A., Katzmarzyk, P. T., Onywera, V. O., Reilly, J. J., & Tomkinson, G. R. (2016). Global Matrix 2.0: Report card grades on the physical activity of children and youth comparing 38 countries. Journal of Physical Activity and Health, 13(11 Suppl 2), S343–S366. doi:10.1123/jpah.2016-0594