Désirée B. Maltais

Muscle Strengthening in Children and Adolescents With Spastic Cerebral Palsy: Considerations for Future Resistance Training Protocols

Resistance training of the lower limbs is now commonly used in clinical practice in children and adolescents with spastic cerebral palsy (CP). However, the effectiveness of this type of training is still disputed. The most recently published systematic review with meta-analysis included interventions such as electrical stimulation and resistance training and found insufficient evidence to support or refute the efficacy of these exercises in children with CP. Thus, the aim of this article is to evaluate the extent to which training protocols from the most recent randomized controlled trials are in keeping with the evidence for effective resistance training in children who are developing typically, as reflected in the training guidelines of the National Strength and Conditioning Association. Recommendations for resistance training protocols, based on this evidence and appropriate to children with CP, are provided to help guide both future research and clinical practice for resistance training in children with CP.

Isometric muscle strength in youth assessed by hand-held dynamometry: a feasibility, reliability, and validity study.

Purpose: To determine, with respect to measurement of maximal isometric torque (MIT) using a specific hand-held dynamometer (HHD) protocol, (1) protocol feasibility over a wide age range, (2) intra- and interrater reliability, (3) standard error of measurement, and (4) concurrent validity. Methods: The MIT of selected upper and lower limb muscle groups was assessed (n = 74; age = 4-17.5 years) using a standardized, HHD protocol. Testing was repeated in 20 adolescents (n = 10 for each muscle group), who were also assessed with a Cybex dynamometer. Results: The protocol was feasible for all participants. Mean intra- and interrater reliability [intraclass correlation coefficient (ICC)] varied from 0.75 to 0.98, except for ankle dorsiflexor interrater reliability (mean ICC = 0.67). The standard error of measurement varied from 0.5 to 4.9 Nm and was highest for hip extensors. Mean concurrent validity (ICC) varied from 0.78 to 0.93, except for ankle plantar flexors (mean ICC = 0.48). Conclusions: Our HHD protocol was feasible over a wide age range and most MIT values were valid and reliable.

Use of orthoses lowers the O2 cost of walking in children with spastic cerebral palsy

PURPOSE The aim of this study was to assess the effects of hinged ankle foot orthoses (AFO) on the metabolic and cardiopulmonary cost of walking and gross motor skills of children with cerebral palsy (CP). METHODS Ten habitual users of hinged AFO with spastic diplegic CP (9.01 yr +/- 2.10) participated in the study. Expired gas and heart rate (HR) were measured during sitting and with AFO on and off during steady state treadmill walking at three speeds: 3 km.h(-1), comfortable walking speed (CWS), and 90% of their fastest walking speed (FWS). Comfortable and fastest ground walking speed and Gross Motor Function Measure scores were also assessed with AFO on and off and analyzed with ANOVA. Because not all children could walk at all speeds on the treadmill, an ANOVA was performed on data for children who walked at 3 km.h(-1) and CWS (N = 8 for HR; N = 9 for pulmonary ventilation and metabolic variables) and a t-test on data at 90% of FWS (N = 9 for HR; N = 8 for pulmonary ventilation and metabolic variables). RESULTS When children wore their AFO net oxygen uptake (L.min(-1), absolute--sitting values) was significantly (P < 0.05) reduced by 8.9% at 3 km.h(-1) and by 5.9% at 90% of FWS. Net pulmonary ventilation (L.min(-1)) was significantly (P < 0.05) lower with AFO on by 10.3% but only at 3 km.h(-1). AFO did not affect net HR (beats.min(-1)) nor the respiratory exchange ratio at any speed, nor any physiologic variable at CWS, nor gross motor skills. CONCLUSIONS Use of hinged AFO reduces the oxygen and ventilatory cost of walking in children with spastic diplegic CP.

The 220-age equation does not predict maximum heart rate in children and adolescents

Our primary purpose was to provide maximum heart rate (HRmax) values for ambulatory children with cerebral palsy (CP). The secondary purpose was to determine the effects of age, sex, ambulatory ability, height, and weight on HRmax. In 362 ambulatory children and adolescents with CP (213 males and 149 females; age range 6–19y; 195 spastic unilateral, 162 spastic bilateral, and five ataxic CP), HRmax was measured during a 10‐m (Gross Motor Function Classification System [GMFCS] levels I and II) or 7.5 m (GMFCS level III) shuttle run test. The mean HRmax was 194 (SD 9.9) beats per minute (bpm), with a 95% prediction interval between 174 and 214 bpm. No associations were found in HRmax related to age, sex, ambulatory ability, height, and weight. Since the HRmax did not vary with age, equations such as 220‐age are not appropriate. When direct evaluation of HRmax with exercise testing is not feasible, we suggest the mean value of 194 bpm be considered as an estimate of HRmax at the individual level.

Identification of a Core Set of Exercise Tests for Children and Adolescents with Cerebral Palsy: A Delphi Survey of Researchers and Clinicians.

Aim  Evidence‐based recommendations regarding which exercise tests to use in children and adolescents with cerebral palsy (CP) are lacking. This makes it very difficult for therapists and researchers to choose the appropriate exercise‐related outcome measures for this group. This study aimed to identify a core set of exercise tests for children and adolescents with CP.

Habitual physical activity levels are associated with biomechanical walking economy in children with cerebral palsy.

Maltais DB, Pierrynowski MR, Galea VA, Matsuzaka A, Bar-Or O: Habitual physical activity levels are associated with biomechanical walking economy in children with cerebral palsy. Am J Phys Med Rehabil 2005;84:36–45. Objective:To evaluate in children and adolescents with cerebral palsy the relationship between habitual physical activity and biomechanical treadmill walking economy and whether treadmill belt speed or walking time affect economy. Design:Physical activity was measured in 11 subjects (10.6–16.3 yrs) with mild cerebral palsy using a triaxial accelerometer. To determine biomechanical walking economy, subjects’ stride lengths and vertical sacral excursions were measured during each minute of three 3-min walks on a treadmill (at 60%, 75%, and 90% of individually determined fastest treadmill walking speed). Results:Biomechanical walking economy at 60%, 75%, and 90% of (their) fastest speed each explained about half of the intersubject variance in daily physical activity (movement counts). A similar relationship was found between these biomechanical walking economy variables and movement counts at or above the 80th and 90th percentile (total minutes per day, number of 5-min bouts per day). Walking economy was 23.9% higher when subjects walked at 90% than when they walked at 60% of their fastest walking speed. No other speed-related effects on economy were found, nor did time affect economy. Conclusions:Within this population, those with high biomechanical treadmill walking economy are the more habitually physically active. Treadmill belt speed, but not walking time, affects biomechanical walking economy.

Identification of a core set of exercise tests for children and adolescents with cerebral palsy

Aim  Evidence‐based recommendations regarding which exercise tests to use in children and adolescents with cerebral palsy (CP) are lacking. This makes it very difficult for therapists and researchers to choose the appropriate exercise‐related outcome measures for this group. This study aimed to identify a core set of exercise tests for children and adolescents with CP.

Health-Related Physical Fitness for Children With Cerebral Palsy

Low levels of physical activity are a global health concern for all children. Children with cerebral palsy have even lower physical activity levels than their typically developing peers. Low levels of physical activity, and thus an increased risk for related chronic diseases, are associated with deficits in health-related physical fitness. Recent research has provided therapists with the resources to effectively perform physical fitness testing and physical activity training in clinical settings with children who have cerebral palsy, although most testing and training data to date pertains to those who walk. Nevertheless, on the basis of the present evidence, all children with cerebral palsy should engage, to the extent they are able, in aerobic, anaerobic, and muscle-strengthening activities. Future research is required to determine the best ways to evaluate health-related physical fitness in nonambulatory children with cerebral palsy and foster long-term changes in physical activity behavior in all children with this condition.

Factors related to physical activity in adults with cerebral palsy may differ for walkers and nonwalkers.

Maltais DB, Dumas F, Boucher N, Richards CL: Factors related to physical activity in adults with cerebral palsy may differ for walkers and nonwalkers. Objective:To explore what factors besides walking ability, e.g., additional health problems or complications, general health, and sociodemographic status, may be related to physical activity in adults with cerebral palsy. Design:We administered a questionnaire regarding sociodemographic and health-related factors of potential relevance to physical activity to 66 men (20–41 yrs) and 66 women (18–39 yrs) with various types of cerebral palsy. Data were analyzed using logistic regression. Results:Use of walking as the primary means of self-transport (walking ability) was associated with a higher odds of being physically active (odds ratio = 3.75; P = 0.002). Among those who could walk, being younger and having a positive perception of health were also associated with a higher odds of being active (odds ratios of 2.6 and 3.0, respectively). This was not true among nonwalkers. For individuals who walked, inactivity was associated with an increase in the severity (during the past 3 yrs) of several additional health problems or complications. For the nonwalkers, inactivity was most clearly associated with perceived range-of-motion limitations. Conclusions:Among adults with cerebral palsy, the ability to walk, as expected, is associated with being physically active. The factors additionally related to physical activity differ between walkers and nonwalkers.

Translation, cross-cultural adaptation and validation of the French version of the Knee Outcome Survey–Activities of Daily Living Scale

Purpose: The Activities of Daily Living Scale of the Knee Outcome Survey (KOS-ADLS) is a joint-specific questionnaire measuring functional limitation experienced by individuals with knee disorders. The original English version of the KOS-ADLS has been shown to be highly reliable and responsive to change. The purpose of this study was to perform a translation and cross-cultural adaptation of the original version of the KOS-ADLS questionnaire into French and to validate this French version of the questionnaire. Method: In accordance with standard procedure, the original version of the KOS-ADLS was translated and cross-culturally adapted into French. Once the final French version of the KOS-ADLS was developed, it was subjected to further psychometric evaluation with 76 individuals with knee disorders. Each participant completed the KOS-ADLS on three occasions: at baseline, two days later to evaluate test–retest reliability, and four weeks later to evaluate responsiveness. Symptoms and function-oriented construct questions were also completed to evaluate construct-convergent and known-group validity. Results: The cross-cultural adaptation procedure revealed no major problems with content or language. The French version of the KOS-ADLS showed excellent test–retest reliability with low measurement error (intraclass correlation coefficient = 0.92, minimal detectable change = 8.3), as well as high responsiveness (standardized response mean = 1.41; clinically important difference = 13.6). Further, it discriminates between different levels of self-rated or clinician-rated knee function. Conclusions: The French version of the KOS-ADLS is a reliable, valid and responsive questionnaire for the assessment of functional limitation in individuals with musculoskeletal knee disorders.