Bart C. Bongers

The oxygen uptake efficiency slope in children with congenital heart disease: construct and group validity

Objective: The oxygen uptake efficiency slope (OUES) has been proposed as an independent and objective alternative to the peak oxygen uptake (VO2peak), which does not require maximal exercise. The aim of this study was to investigate the construct and group validity of the OUES in children with congenital heart disease (CHD). Methods: Thirty-one patients with CHD, of which 16 patients (mean age ± SD 11.2 ± 2.7 years) with a Fontan repair and 15 patients (mean age ± SD 13.2 ± 3.6 years) with surgical repair of tetralogy of Fallot (ToF) completed a symptom-limited cardiopulmonary exercise test. The OUES was calculated and normalized for body surface area at three different exercise intensities: (1) using 100% of the exercise data; (2) using the first 75% of the exercise data; and (3) using exercise data up to the ventilatory threshold (VT). Furthermore, peak oxygen uptake (VO2peak), VT, ventilatory efficiency (VE/VO2-slope), and ventilatory drive (VE/VCO2-slope) were calculated and compared with values of 46 healthy children (mean age ± SD 12.2 ± 2.4 years). Results: In all three groups, the OUES values determined at the three different exercise intensities were not significantly different from each other. Moreover, the OUES was significantly reduced in the children with CHD, with significantly lower values in the Fontan patients compared to ToF. Strong correlations were found between the OUES and both the VO2peak and VT in Fontan and ToF patients. Discussion: The OUES provides a valid measure of cardiopulmonary fitness in children with CHD, which is independent of exercise intensity and strongly correlated with VO2peak and VT (construct validity). Furthermore, the OUES is capable of differentiating between healthy children and children with CHD and between Fontan and ToF patients (group validity). Therefore, the OUES may be a valid, effort-independent parameter of cardiopulmonary fitness in children with CHD.

Efficacy and Safety of Bisphosphonate Therapy in Children with Osteogenesis Imperfecta: A Systematic Review

Background/Aims: To systematically assess contemporary knowledge regarding the effectiveness and safety of bisphosphonates (BPs) in children with osteogenesis imperfecta (OI). Methods: PubMed/MEDLINE, Embase, and Cochrane were searched for eligible articles up to June 2014. Studies eligible for inclusion were (randomized) controlled trials assessing the effects of BPs in children with OI. Methodological quality was assessed independently by 4 reviewers using the Cochrane Collaborations tool for risk of bias. Results: Ten studies (519 children) were included. Four studies (40%) showed a low risk of bias. All studies investigating lumbar spine areal bone mineral density indicated a significant increase as a result of BP treatment. Most studies observed a significant decrease in fracture incidence. The most frequently reported adverse events were gastrointestinal complaints, fever, and muscle soreness. A significant decrease in (bone) pain due to BP treatment was observed in more than half of the studies. Most studies measuring urinary markers of bone resorption reported a significant decrease. The majority of studies with intravenous treatment showed a significant increase in lumbar projection area, whereas studies with oral treatment did not. Conclusions: Treatment with oral or intravenous BPs in children with OI results in an increase in bone mineral density and seems to be safe and well tolerated.

Validity of the muscle power sprint test in ambulatory youth with cerebral palsy.

Purpose: To validate the Muscle Power Sprint Test (MPST) against the Wingate Anaerobic cycling Test (WAnT) in a group of youth with cerebral palsy (CP). Methods: Twenty children and adolescents (11 boys and 9 girls; mean age = 14.8 years) with spastic CP, and classified as either level I or II of the Gross Motor Function Classification System, completed the study. Results: Very strong significant correlations were seen for peak power (PP) and mean power (MP) from the MPST and WAnT PP and MP values (PP: r = 0.731, P < .001; MP: r = 0.903, P < .001). Conclusions: The results of this study show that the MPST is a valid test for measuring anaerobic capacity in children with CP, and that this test can be used as an evaluation tool for anaerobic performance in exercise interventions focusing on children and adolescents with CP who are able to walk or run independently.

The Steep Ramp Test in Healthy Children and Adolescents: Reliability and Validity

PURPOSE This study aimed to examine the reliability and validity of the steep ramp test (SRT), a feasible, maximal exercise test on a cycle ergometer that does not require the use of respiratory gas analysis, in healthy children and adolescents. METHODS Seventy-five children were randomly divided in a reliability group (n = 37, 17 boys and 20 girls; mean ± SD age = 13.86 ± 3.22 yr), which performed two SRTs within 2 wk, and a validity group (n = 38, 17 boys and 21 girls; mean ± SD age = 13.85 ± 3.20 yr), which performed both an SRT and a regular cardiopulmonary exercise test (CPET) with respiratory gas analysis within 2 wk. Peak work rate (WRpeak) was the main outcome of the SRT. Peak oxygen uptake (VO2peak) was the main outcome of the CPET. Reliability was examined with the intraclass correlation coefficient and a Bland and Altman plot, whereas validity was assessed using Pearson correlation coefficients and stepwise linear regression analysis. RESULTS Reliability statistics for the WRpeak values attained at the two SRTs showed an intraclass correlation coefficient of 0.986 (P < 0.001). The average difference between the two SRTs was -6.4 W, with limits of agreement between +24.5 and -37.5 W. A high correlation between WRpeak attained at the SRT and the V˙O2peak achieved during the CPET was found (r = 0.958; P < 0.001). Stepwise linear regression analysis provided the following prediction equation: VO2peak (mL·min) = (8.262 WRpeak SRT) + 177.096 (R2 = 0.917, SEE = 237.4). CONCLUSION The results suggest that the SRT is a reliable and valid exercise test in healthy children and adolescents, which can be used to predict VO2peak.

Physiological Demands of Therapeutic Horseback Riding in Children With Moderate to Severe Motor Impairments: An Exploratory Study

Purpose: To examine energy expenditure at rest and during a single therapeutic horseback riding (THR) session in children with moderate to severe motor impairments. Methods: Heart rate (HR), oxygen uptake ( O2), and minute ventilation ( E) were measured continuously during a 10-minute rest period and during a typical THR session. Results: Seven children (4 males, mean age 12.3 ± 3.5 years) completed the protocol. Significant increases from rest were seen for mean HR, O2, E, and energy expenditure. Based on O2, 43.3 ± 24.3% of the THR session consisted of sedentary, 44.4 ± 13.4% of light, and 12.3 ± 21.8% of moderate to vigorous activity intensity, with large interindividual differences. Conclusions: The physiological demands of THR in children with moderate to severe motor impairments are moderate. However, considering the short duration of maintaining moderate to vigorous exercise activity during THR in combination with the low training frequency, group data indicate that it is unlikely that THR will improve cardiopulmonary fitness in these children.

Validity of the Pediatric Running-Based Anaerobic Sprint Test to Determine Anaerobic Performance in Healthy Children.

PURPOSE To determine criterion validity of the pediatric running-based anaerobic sprint test (RAST) as a nonsophisticated field test for evaluating anaerobic performance in healthy children and adolescents. METHODS Data from 65 healthy children (28 boys and 37 girls between 6 and 18 years of age, mean ± SD age: 10.0 ± 2.8 years) who completed both the pediatric RAST and the 30-s Wingate anaerobic test (WAnT) on a cycle ergometer in a randomized order were analyzed. Peak power (PP) and mean power (MP) were the primary outcome measures for both tests. RESULTS There were no significant sex-differences in PP and MP attained at the pediatric RAST and the WAnT. Age was strongly correlated to pediatric RAST and WAnT performance (Spearmans rho values ranging from 0.85 to 0.90, with p < .001 for all coefficients). We found high correlation coefficients between pediatric RAST performance and WAnT performance for both PP (Spearmans rho: 0.86; p < .001) and MP (Spearmans rho: 0.91; p < .001). CONCLUSION The pediatric RAST can be used as a valid and nonsophisticated field test for the assessment of anaerobic performance in healthy children and adolescents. For clinical evaluative purposes, we suggest to use MP of the pediatric RAST when assessing glycolytic power in the absence of the WAnT.

The Steep Ramp Test in Dutch White Children and Adolescents: Age- and Sex-Related Normative Values

Background The Steep Ramp Test (SRT), a feasible, reliable, and valid exercise test on a cycle ergometer, may be more appealing for use in children in daily clinical practice than the traditional cardiopulmonary exercise test because of its short duration, its resemblance to childrens daily activity patterns, and the fact that it does not require respiratory gas analysis. Objective The aim of the present study was to provide sex- and age-related normative values for SRT performance in Dutch white children and adolescents who were healthy and 8 to 19 years old. Design This was a cross-sectional, observational study. Methods A total of 252 Dutch white children and adolescents, 118 boys (mean age=13.4 years, SD=3.0) and 134 girls (mean age=13.4 years, SD=2.9), performed the SRT (work rate increment of 10, 15, or 20 W·10 s−1, depending on body height) to voluntary exhaustion to assess peak work rate (WRpeak). Normative values are presented as reference centiles developed by use of generalized additive models for location, scale, and shape. Results Peak work rate correlated highly with age (r=.915 and r=.811), body mass (r=.870 and r=.850), body height (r=.922 and r=.896), body surface area (r=.906 and r=.885), and fat free mass (r=.930 and r=.902) in boys and girls, respectively. The reference curves demonstrated an almost linear increase in WRpeak with age in boys, even when WRpeak was normalized for body mass. In contrast, absolute WRpeak in girls increased constantly until the age of approximately 13 years, when it started to level off. Peak work rate normalized for body mass in girls showed only a slight increase with age until 14 years of age, when a slight decrease in relative WRpeak was observed. Limitations The sample may not have been entirely representative of the Dutch population. Conclusions The present study provides sex- and age-related normative values for SRT performance in terms of both absolute WRpeak and relative WRpeak, thereby facilitating the interpretation of SRT results by clinicians and researchers.

Effects of prehabilitation and rehabilitation including a home-based component on physical fitness, adherence, treatment tolerance, and recovery in patients with non-small cell lung cancer: A systematic review

This systematic review aimed to examine physical fitness, adherence, treatment tolerance, and recovery for (p)rehabilitation including a home-based component for patients with non-small cell lung cancer (NSCLC). PRISMA and Cochrane guidelines were followed. Studies describing (home-based) prehabilitation or rehabilitation in patients with NSCLC were included from four databases (January 2000-April 2016, N=11). Nine of ten rehabilitation studies and one prehabilitation study (437 NSCLC patients, mean age 59-72 years) showed significantly or clinically relevant improved physical fitness. Three (27%) assessed home-based training and eight (73%) combined training at home, inhospital (intramural) and/or at the physiotherapy practice/department (extramural). Six (55%) applied supervision of home-based components, and four (36%) a personalized training program. Adherence varied strongly (9-125% for exercises, 50-100% for patients). Treatment tolerance and recovery were heterogeneously reported. Although promising results of (p)rehabilitation for improving physical fitness were found (especially in case of supervision and personalization), adequately powered studies for home-based (p)rehabilitation are needed.

The paediatric version of the steep ramp test

Exercise tests to determine cardiopulmonary fitness are commonly used by physiotherapists working with children and adolescents. However, there is a need for an easy-to-use exercise test, which does not require respiratory gas analysis and is suitable for the clinical situation. The paediatric version of the steep ramp test (SRT) is such a test. It is simple and only requires a stationary bike. People are required to cycle against rapidly increasing workloads. The primary outcome measure is the achieved maximal workload (Wpeak, in Watts). The paediatric version of the SRT consists of a three-minute warm up at 25 Watts, followed by an increase in workload of 10, 15 or 20 Watts every 10 seconds, depending on the child’s body height (< 120 cm, between 120 and 150 cm, and > 150 cm, respectively). This contrasts with the adult version of the SRT, which consists of three minutes of unloaded cycling, followed by a rapid increase in workload of 25 Watts every 10 seconds until exhaustion. To assess a child’s Wpeak more accurately, a ramp version of the SRT protocol is recommended (workload increments of 2, 3, or 4 Watts every two seconds). The child is instructed to maintain a pedalling frequency of approximately 80 rpm, and the protocol continues until the child is no longer able to maintain a pedalling frequency of 60 rpm, despite strong verbal encouragement. This point is defined as peak exercise. Other measurements such as heart rate, oxygen saturation, blood pressure and dyspnoea or exertion can be used to provide additional information. Paediatric normal values for children and adolescents aged

Cardiopulmonary Exercise Testing in Pediatrics

&NA; Aerobic fitness is an important determinant of overall health. Higher aerobic fitness has been associated with many health benefits. Because myocardial ischemia is rare in children, indications for exercise testing differ in children compared with adults. Pediatric exercise testing is imperative to unravel the physiological mechanisms of reduced aerobic fitness and to evaluate intervention effects in children and adolescents with a chronic disease or disability. Cardiopulmonary exercise testing includes the measurement of respiratory gas exchange and is the gold standard for determining aerobic fitness, as well as for examining the integrated physiological responses to exercise in pediatric medicine. As the physiological responses to exercise change during growth and development, appropriate pediatric reference values are essential for an adequate interpretation of the cardiopulmonary exercise test.