The indications for exercise testing in children and adolescents with cerebral palsy (CP) are broad and have as a general goal the evaluation of exercise performance and mechanisms that limit performance in the individual. Exercise testing over time can provide a quantitative assessment of the improvement or decline in the exercise capacity of children and adolescents with CP.
The selection of appropriate outcome measures is crucial in exercise evaluation. Outcomes need to be relevant to patients, practitioners, and policymakers if the findings of the research are to influence practice and future research. Moreover, because of the physical limitations imposed by CP, modifications of standard testing protocols are often necessary and should be geared to the degree of the child's physical abilities.
In 2010, a Delphi study was performed to identify a core set of field and laboratory exercise tests for children and adolescents with CP.1 This survey, conducted with physical therapists, exercise physiologists, and researchers resulted in a core set of measures in 3 fitness categories (submaximal, maximal, and anaerobic exercise tests) for children and adolescents with CP with various Gross Motor Function Classification System (GMFCS) levels.1 The core set from 2011 and a previously published systematic review from 2013 on clinimetric properties of fitness tests in CP identified a lack of reliable laboratory tests.1,2 Especially, appropriate exercise tests for children classified as GMFCS level III and IV were lacking.1,2
To improve the standardization of exercise tests across studies, thereby facilitating the comparison of study results or clinical programs, the core set of exercise tests needed to be updated.
Using the published core set as a starting point, we identified additional submaximal, maximal, and anaerobic exercise test outcome measures for children and adolescents with CP. We performed a comprehensive literature search in 4 databases (PubMed, EMBASE, SPORTDiscus, and PsychINFO) from 2010 to July 2014 to identify fitness-related outcome measures for children with CP. This search was performed using the MeSH term and text words for (“physical fitness” OR “aerobic capacity” OR “anaerobic capacity” OR “exercise test”) AND “cerebral palsy” AND (“children” OR “adolescents”). Additional outcome measures were identified and divided into the previously defined 3 fitness categories: (1) submaximal exercise tests; (2) maximal exercise tests; and (3) anaerobic exercise tests.
The search revealed an additional 6 papers on outcome measures based on the previously defined set by the Delphi committee. The identified laboratory- and field-based exercise tests met the criteria for good reliability1,2,2–8: intraclass correlation coefficients of 0.7 or more or Pearson correlation coefficient of 0.8 or more; and good validity5,6: correlation coefficient of 0.7 or more or 75% or more of the results in accordance with the hypothesis.9 Included studies were listed and sorted by GMFCS levels for each fitness category and divided into field-based tests and laboratory-based tests. Moreover, for all tests that are included in this core set, it is indicated whether the aforementioned criteria related to reliability and/or validity are met. Based on this information, the exercise tests core set is updated, as presented in Table 1.
Categorizing the Outcome Measures
Since most children classified as GMFCS levels I and II are able to walk and cycle, tests were identified for both of these motor skills for this group of children. Children classified as GMFCS level III are able to walk and cycle and sometimes propel a manual wheelchair for short or longer distances. Therefore, for this subgroup, the tests that were identified related to walking, cycling, propelling a wheelchair, and arm cranking (which is a skill more closely related to wheelchair propelling than either cycling or walking). For children classified as GMFCS level IV, the core set included tests that were related to propelling a wheelchair, cycling, and arm cranking.
Condition-Specific Norm Values
Recently, CP-specific norm values have been published for the 10-m Shuttle Run Test (GMFCS I & II)17 and the Muscle Power Sprint Test (GMFCS I and II).18 For all other listed tests in Table 1, norm values have not been established.
This update shows an exercise test core set from which a submaximal, maximal, or anaerobic exercise test can be selected for children with CP, classified as GMFCS I to IV.
1. Verschuren O, Ketelaar M, Keefer D, et al. Identification of a core set of exercise tests for children and adolescents with cerebral palsy: a Delphi survey of researchers and clinicians. Dev Med Child
2. Balemans AC, Fragala-Pinkham MA, Lennon N, et al. Systematic review of the clinimetric properties of laboratory- and field-based aerobic and anaerobic fitness measures in children with cerebral palsy. Arch Phys Med Rehabil. 2013;94:287–301.
3. Brehm MA, Balemans AC, Becher JG, Dallmeijer AJ. Reliability of a progressive maximal cycle ergometer test to assess peak oxygen uptake in children with mild to moderate cerebral palsy. Phys Ther. 2014;94:121–128.
4. Dallmeijer AJ, Scholtes VA, Brehm MA, Becher JG. Test-retest reliability of the 20-sec Wingate test to assess anaerobic power in children with cerebral palsy. Am J Phys Med Rehabil. 2013;92:762–767.
5. Verschuren O, Zwinkels M, Obeid J, Kerkhof N, Ketelaar M, Takken T. Reliability and validity of short-term performance tests for wheelchair-using children and adolescents with cerebral palsy. Dev Med Child
6. Verschuren O, Zwinkels M, Ketelaar M, Reijnders-van Son F, Takken T. Reproducibility and validity of the 10-meter Shuttle Ride Test in wheelchair-using children and adolescents with cerebral palsy. Phys Ther. 2013;93:967–974.
7. Verschuren O, Bosma L, Takken T. Reliability of a shuttle run test for children with cerebral palsy who are classified at Gross Motor Function Classification System level III. Dev Med Child
8. Verschuren O, Ketelaar M, De Groot J, Vila Nova F, Takken T. Reproducibility of two functional field exercise tests for children with cerebral palsy who self-propel a manual wheelchair. Dev Med Child
9. Terwee CB, Mokkink LB, Knol DL, Ostelo RW, Bouter LM, de Vet HC. Rating the methodological quality in systematic reviews of studies on measurement properties: a scoring system for the cosmin checklist. Qual Life Res. 2012;21:651–657.
10. Maher CA, Williams MT, Olds TS. The Six-Minute Walk Test for children with cerebral palsy. Int J Rehabil Res. 2008;31:185–188.
11. Thompson P, Beath T, Bell J, et al. Test-retest reliability of the 10-metre fast walk test and 6-minute walk test in ambulatory school-aged children with cerebral palsy. Dev Med Child
12. Unnithan VB, Katsimanis G, Evangelinou C, Kosmas C, Kandrali I, Kellis E. Effect of strength and aerobic training in children with cerebral palsy. Med Sci Sports Exerc. 2007;39:1902–1909.
13. Verschuren O, Takken T, Ketelaar M, Gorter JW, Helders PJ. Reliability and validity of data for 2 newly developed shuttle run tests in children with cerebral palsy. Phys Ther. 2006;86:1107–1117.
14. Berg-Emons van den RJ, van Baak MA, de Barbanson DC, Speth L, Saris WH. Reliability of tests to determine peak aerobic power, anaerobic power and isokinetic muscle strength in children with cerebral palsy. Dev Med Child
15. Verschuren O, Takken T, Ketelaar M, Gorter JW, Helders PJ. Reliability for running tests for measuring agility and anaerobic muscle power in children and adolescents with cerebral palsy. Pediatr Phys Ther. 2007;19:108–115.
16. Verschuren O, Bongers BC, Obeid J, Ruyten T, Takken T. Validity of the muscle power sprint test in ambulatory youth with cerebral palsy. Pediatr Phys Ther. 2013;25(1):25–28.
17. Verschuren O, Bloemen M, Kruitwagen C, Takken T. Reference values for aerobic fitness in children, adolescents, and young adults who have cerebral palsy and are ambulatory. Phys Ther. 2010;90:1148–1156.
18. Verschuren O, Bloemen M, Kruitwagen C, Takken T. Reference values for anaerobic performance and agility in ambulatory children and adolescents with cerebral palsy. Dev Med Child