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Commentary on “Physical Activity of Children With a Mitochondrial Disease Compared to Children Who Are Healthy”

Hollandsworth, R. Caprice PT, DPT; Grant-Beuttler, Marybeth PT, PhD, PCS

Pediatric Physical Therapy: April 2014 - Volume 26 - Issue 1 - p 27
doi: 10.1097/PEP.0000000000000017
Clinical Bottom Line

Orange County Therapy Services San Clemente, California

Chapman University Orange, California

The authors declare no conflicts of interest.

“How should I apply this information?”

This study emphasized baseline differences in physical activity among children with mitochondrial myopathy (MM) across all levels of disability compared to peers who are healthy.1–3 The groups demonstrated large effect sizes in moderate to vigorous physical activity time per day (d = 1.1), level of fatigue (d = 1.7), and the time heart rate was above aerobic threshold (d = 0.9).4 Physical therapists need to take advantage of clinically applicable and accessible tools to document achievable improvements over those attributable to development. Attention to activity level and duration through estimated metabolic equivalent, use of accelerometers, and participation inventories will allow therapists to promote periods of increased activity to optimize each child's plan of care. Considering children with MM rated fatigue highest at the end of the school day, the addition of specific school function and pulmonary measures may enhance interventions targeting energy expenditure and physical limitations. Specific goals, which balance improvements in body mass index, endurance, aerobic capacity, and physical independence at school and home, could positively affect quality of life (QOL).

“What should I be mindful about when applying this information?”

Demographics revealed a confounding variable, body mass index (d = 2.9), which may result from and/or contribute to decreased activity.

It is also important to note that heart rate and activity level were collected only during the school day; nonschool activity distinctions may be higher compared with children who are healthy who participate in sports. Such significant differences between elements of activity (type, intensity, and duration) and reported fatigue lead us to question whether activity capacity is being optimized or if perceived exertion is directing activity level. As pediatric therapists, examining activity at all disablement levels will allow us to better understand the interaction of activity and perceived fatigue, improving interventions, and education vital to QOL.

This article focused on children with MM, but evaluating activity level and capacity in children with other disabilities is important to maximize QOL, particularly in light of the current obesity epidemic.

R. Caprice Hollandsworth, PT, DPT

Orange County Therapy Services

San Clemente, California

Marybeth Grant-Beuttler, PT, PhD, PCS

Chapman University

Orange, California

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1. Guccione AA. Physical therapy diagnosis and the relationship between impairments and function. Phys Ther. 1991;71:499–504.
2. Jette AM. Physical disablement concepts for physical therapy research and practice. Phys Ther. 1994;74:380–386.
3. World Health Organization. International Classification of Functioning, Disability and Health (ICF). Accessed September 22, 2013.
4. Wilson D. Practical Effect Size Calculator. The Campbell Collaboration, George Mason University. February 2013.
© 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins and the Section on Pediatrics of the American Physical Therapy Association.