Measuring physical fitness in Persons with Severe/Profound ...

In order to confirm the validity of the aSRT [12], results of both the treadmill and aSR testshould be compared to a golden standard [18]. Midgley et al. [19] reviewed available literatureregarding the verification phase following a graded exercise test and suggested performing aSupra Maximal Block Test (SMBT) to set a gold standard for HR peakon an individual basis [19]. Ifthe heart rate of the SMBT differs by no more than two beats from the HR peakreached during thecorresponding aSRT [12], the exertion during the aSRT [12] is scored as maximal [19].The purpose of this study thus is twofold; it seeks to determine the feasibility, validity andtest-retest reliability of a graded treadmill test (GXT) for participants with SIMD and GMFCS levelI, using a Supra Maximal Block Test (SMBT) as golden standard. By doing so, this study will alsoassess whether the formula of Fernhall overestimates HR peakin persons with SIMD.MethodsParticipantsThe participants were recruited from a residential care facility in the Netherlands, which ishome to 200 persons with severe or profound intellectual and visual disabilities. Only personsfunctioning at GMFCS-I level were included, because Waninge et al. have indicated the aSRTperformed over ground is only reliable for persons with GMFCS level I [12]. Probably due tovisual impairments, the participants were not able to run and jump spontaneously [5, 7, 12].Subsequently, classification was adjusted so as to include people with GMFCS-I who were able toincrease walking speed [12].A total of 30 participants were recruited (17 males, 13 females), all classified as GMFCS-I.Twenty-three participants had a severe ID and seven a profound ID. Some could not walk alonebecause of a visual impairment. Table 1 presents the participants’ characteristics.Table 1. PopulationMale (n=17) Female (n=13) Total (n=30)Age Mean (SD) 40 (11) 42 (11) 41 (11)IDSevere ID(20≤IQ