Children have a basic need for motor activity. This elementary need to move is biologically based and guaranteed by the dominance of central nervous excitation processes. Movement serves as a catalyst in the child’s development, especially in younger children. A high level of movement ensures the advancement of the child’s physical development, especially the locomotor system, which through movement gains the impulses needed for its normal development [19, 20]. In contrast, physical inactivity in childhood is abnormal – regardless of whether it is due to physical, emotional, psychosocial or cognitive factors [20]. Establishing contacts self-confidently, thoughtfulness, cooperation, benchmarking, competence, abiding by rules and participating in group activities are important behaviours which preschool children mainly learn by taking part in active games with peers. As early as preschool age, good motor abilities, skilfulness and strength improve a child’s social reputation with his/her group of peers, thereby improving self-confidence and supporting the development of emotional stability and positive self-image; this is even more pronounced at early school age [19]. Thus the children’s perceptual and motor experience not only determines their physical and motor development but also decisively influences their emotional, psychosocial and cognitive development. Deficiency in this field might affect the children’s entire personal development in a negative way [19–21].

Often, cardiac disease means a restriction of the affected child’s perceptual and motor experience. Complex and severe heart defects may, at least temporarily, cause reduced symptom-limited exercise tolerance and therefore require a certain amount of rest. Times of inpatient examinations or corrective operations are always periods of more or less strict immobilisation. Depending on their duration and the child’s age and mental stability, cardiac disease can lead to developmental stagnation or regression. Great uncertainty exists especially with regard to the danger to which one might expose children by allowing them to engage in physical activity. This is often – unnecessarily – also the case with children whose physical capacities are grossly normal [20, 21]. Figure 13.2 shows the conditional network of possible causes and effects of physical inactivity in children with heart diseases.

Relatively few studies [19, 21–25] have focused on the motor development in children with congenital malformed heart (Fig. 13.3). All studies but one [25] performed have demonstrated that deficits in motor development can be expected in a relatively large group of affected children and adolescents. In a large study [21] the motor development in 194 subjects with congenital malformations of the heart was compared with that of a representative control group of healthy peers. The classification of the motor development demonstrated 58.7 % of the children with heart disease to have moderate to severe deficits in gross motor skills and 31.9 % to have severe deficits (Fig. 13.4). In the group of children with CHD, no differences were found for gender, but older children and adolescents (aged 11–15 years) had more severe deficits compared to younger children (5–10 years of age; p < 0.01). The mean age- and gender-adjusted motor quotient was significantly lower in the group of children with CHD compared to the control group. This was seen in the children with significant residual sequelae as well as in those with no or mild residual sequelae (Fig. 13.5). This is especially noticeable since there is no reason for any restriction of physical activity in the children with mild uncorrected lesions or without residual sequelae after previous surgery.

Another large study investigated the motor competence in children with complex congenital heart disease [18]. The results of 120 children (aged 7–12 years) who had undergone a surgical repair with multiple and complex correction within the first year of life were compared with that of 387 healthy school children at same age. Children with CHD scored significantly worse for manual dexterity, ball skills, grip strength, quadriceps muscle strength and static and dynamic balance (Fig. 13.6). Compared with the healthy peers, children with complex congenital heart disease had 5.8-fold (95 % confidence interval, 3.8–8.8) risk of having some degree of impaired motor competence. The risk for having severe motor disturbances was 11-fold (95 % confidence interval, 5.4–22.5) [18].

The results of studies investigating the exercise tolerance of children and young adults with various forms of congenital heart diseases demonstrate that depending on the severity of the defect, the success of corrective procedures and the presence and degree of residual sequelae, physical performance may be limited [26–38]. However, the findings show that even children with mild uncorrected lesions or without residual sequelae after previous surgery may reveal a substantial reduction in their physical performance [27, 28, 37].

Fredriksen et al. [27] compared the peak oxygen uptake (VO_2peak) of 169 children and adolescents (91 boys, 78 girls, aged 8–16 years) with congenital heart disease with that of a representative control group of 196 healthy pears. The results demonstrated that patients with CHD exhibited lower VO_2peak values in all age groups, with declining values for boys after the age of 12–13 years (Fig. 13.7). While patients with tetralogy of Fallot had lower VO_2peak values, they made approximately the same progress with age as healthy peers. A marked decline in VO_2peak was seen in patients with transposition of the great arteries after the age of 12–13 years. These results have been confirmed in more recently published studies showing reduced exercise capacity in children, adolescents and young adults (aged 6–25 years) with various CHD diagnosis. They revealed VO_2peak to be markedly reduced by 60–82 % of that predicted [33, 35, 36, 38].

Some studies have evaluated the physical activity patterns in children and adolescents with CHD and [38–43] and in the majority of the cases found it to be reduced compared to healthy pears.

A study investigating the activity patterns of 54 children and adolescents (aged 7–14 years) after neonatal arterial switch operation using 24 h continuous heart rate monitoring revealed that these patients do not meet the guideline for physical activity. Compared to the results of 124 age-matched healthy children, the CHD group was significantly less active. This was true for moderate and vigorous activities. The results revealed only 19 and 27 % of the CHD patients engaged in more than 30 min a day of moderate activity and 20 min a day in vigorous activity, respectively [42]. McCrindle et al. [43] demonstrated that in children and adolescents after Fontan procedure, the measured time spent in moderate and vigorous activity was markedly below normal at all age. This was seen particularly in female patients and was not significantly related to self-reported activity levels or to VO_2peak levels [43].

O’Bryne et al. [38] evaluated the habitual exercise habits in 88 subjects (12.6 ± 3.3 years) with conotruncal abnormalities. They revealed median amount of weekly exercise to be 4 h (interquartile range 0–2, 2–4, 4–9.7, and 9.7–24 h/week). The VO_2peak was 76 ± 21 % of that predicted. They found hours of weekly habitual exercise to be correlated with exercise performance. Arvidsson et al. [40] evaluated the physical activity level and physical performance in 32 children aged 9–11 years and 25 adolescents aged 14–16 years with CHD. They found a significant correlation between physical activity level and VO_2peak in 9–11-year-old girls and 14–16-year-old boys and girls but not in the group of 9–11-year-old boys with CHD.

Obesity is also a common comorbidity in children with congenital heart diseases [44]. Findings from Stefan et al. [45] demonstrated exercise-intolerant and activity-restricted children experienced larger increases in the absolute body mass index (BMI) and the BMI percentile than children with neither exercise intolerance nor activity restrictions. In 110 children with congenital heart disease (mean age 8.4 years), activity restriction was the strongest predictor of the risk of being overweight and obese at follow-up [45].

These results emphasise the importance of encouraging children and adolescents with congenital heart disease to engage more in physical activity and exercise training in order to avoid sedentary behaviour in adulthood and prevent atherosclerotic cardiovascular disease.

The impact of a congenital cardiac malformation on the development of the affected child depends on the type and severity of the malformation, as well as the timing and success of therapeutic measures. For some complex malformations with single ventricle physiology, only palliative solutions are available. Lesions such as tetralogy of Fallot [46], atrioventricular septal defect [47] and transposition of the great arteries [46] can be successfully corrected in infancy with good long-term outcome. After successful correction in infancy, most of the children born with cyanotic congenital malformations are able to participate in all normal age-appropriate physical activities with their healthy peers [13–15, 48–54]. While in children with significant postoperative clinical findings some restrictions regarding physical activity might be recommended, the group of children with no or mild residual sequelae do not require any restrictions and should be taking part in normal physical activity. Although it is well recognised that neurological impairment might be caused by pre-/postoperative persistent low cardiac output, acidosis and/or hypoxia or from ischaemia related to surgery and be associated with later neurological deficits [55–59], this alone does not explain the deficits in motor development observed in children with congenital heart diseases. The main studies cited did exclude all children with recognised syndromes, disabilities or comorbidities, which might have affected their motor development. It is more likely that a significant proportion of the deficits in motor development observed are primarily due to lack of efficient bodily perception and movement experience due to restrictions in physical activity. Overprotective behaviour in the children’s parents and teachers could be an important reason for the observed deficits. Mothers of children with congenital heart disease report higher levels of vigilance with their children than mothers of healthy children same aged [60]. Anxiety and overprotecting parents’ attitude might reduce the child’s exposure to peers, not least regarding physical activity, which might influence the child’s social competence, motor development and cause retardation [61]. Parents of children with congenital heart disease are more likely to report elevated levels of parenting stress compared to the normal population [62–64]. This high level of stress is unrelated to the severity of the child’s disease but tends to be higher in parents with older children when it becomes more difficult for them to set limits and maintain control [65]. Mothers are most concerned not only about the medical prognosis of their child but also regarding the child’s quality of life including aspects like functional and physical limitations [65].

Numerous groups of experts have provided recommendations concerning exercise for children with CHD [13–15, 50–53, 66]. These recommendations can contribute to avoiding unnecessary exclusion of children and adolescents with heart disease from physical activity and sport. Moreover, they can minimise children’s, parents’ and teachers’ insecurity in regard to the affected child’s physical abilities. In keeping with these recommendations, all youth with CHD who fulfil the necessary requirements should have the opportunity to participate in physical activity and, if needed, take part in specially adapted programmes of physical education. For the assessment of aptitude and classification, the primary heart defect is less important than the current clinical status and potentially deleterious residual defects (Tables 13.2 and 13.3).

For many of the affected children, no restriction of physical activity and sport is recommended [13–15, 49–50, 53, 66]. This group includes all children and adolescents whose heart defects were definitively corrected in infancy or early childhood (persistent ductus arteriosus, small atrial septal defect, ventricular septal defect), who do not have symptom-limited reduction of exercise capacity (Group 1.1). Even in patients with mild residual defects (Group 1.2) (such as moderate aortic valve disease), normal load can be permitted in physical education and physical activities in leisure time. This also applies to children and adolescents whose cardiac defects do not require surgery (Group 2, for instance, small septal defects or insignificant valvular stenosis) [20, 66]. Patient groups 1.1, 1.2 and 2 do need temporary participation in remedial programmes and/or adapted physical education if a restriction of physical fitness and/or psychomotor deficits exists. In this context, the indication for participation in special exercise-based rehabilitation groups may also result from psychosocial reasons [54].

Despite the reduction in mortality and improved haemodynamic outcomes of surgery and interventional catheterisation, a considerable number of affected children and adolescents have haemodynamically significant residual defects, which may impair their expectancy and quality of life. For them, participation in special exercise-based rehabilitation groups is most recommended. For patients with significant findings, complex heart defects subsequent to palliative interventions, inoperable heart defects, chronic cardiomyopathy, complex arrhythmia or after heart transplantation, participation in physical activity cannot generally be advocated. Here, a decision for each individual patient has to be made in consultation with the attending paediatric cardiologist. Patients with complex heart defects after palliative operations (Group 1.4) represent a special group. In a great number of them (Group 1.4a), a separation of the systemic and pulmonary circulations can be performed, and thus no cyanosis persists. However, some patients remain cyanotic (Group 1.4b). For these groups, and for children receiving anticoagulant therapy or with implanted devices (pacemakers, ICDs) or at a risk of sudden death, special and sometimes individual recommendations have to be made [13–15, 49–50, 53, 66]. Possible contraindications for participation in physical activities are summarised in Table 13.4.

Prior to starting a physical training programme, a thorough cardiological examination has to be performed in order to classify diagnosis and severity of the disease (Table 13.5). The objective of this examination is to determine the patient’s individual symptom-limited exercise tolerance and the risk of exercise-related sudden cardiac death associated with the individual’s specific disease [13–15].

In addition to the required preliminary examinations (Table 13.5), physical activity participation should be assessed at the initial examination as well as at every control checkup. For children up to 10–12 years of age, regular assessment of motor development and different motor skills is recommended [14, 15].

Improvement of physical activity in children with CHD should start as early as possible. In this way, deficits in perceptual and motor experience and their negative consequences can be minimised. Children need to be provided with the opportunity to act out their basic need for physical activity and should only be stopped if there is a specific danger of sudden death. They should participate in physical activity (indoors and outdoors) with their peers in an unrestricted fashion, as far as possible. This applies to play and guided activity in kindergarten, school and/or sports clubs [14–15, 20, 50, 66].

Recommendation for physical activity and exercise training has to include information about the type, contents, intensity, duration and frequency of exercise. The appropriate type of exercise is of main importance. Predominantly static exercise can result in high stress on the systemic and pulmonary circulations, which can have extreme effects on the haemodynamic function in congenital heart disease. Predominantly dynamic type of exercise, however, reduces the afterload and can therefore be expected to have a protective effect [15, 66]. Selected forms of exercise and games in childhood with a high dynamic/low static component are running, skipping, jumping, cycling, swimming, inline skating, skateboarding, running games, ball games and so-called small active games. Types of exercise with a high static/low dynamic component are, for example, climbing, swinging, leaning on both arms, pulling, pushing, martial arts such as judo and gymnastics, e. g. on the high bar or the parallel bars (leaning on both arms, hanging) [15, 66]. Figure 13.8 shows classification of selected organised sports and exercise based on peak static and dynamic components during participation.

Recommendation on exercise intensity should be established and controlled based on the results of an exercise stress test done on a bicycle/treadmill ergometer including ECG and blood pressure monitoring. In physical activities and exercises with high dynamic components, i.e. aerobic endurance activities, heart rate, breathing and rate of individually perceived exertion can be used to assess appropriate intensity (Chap. 4).

Participation in specific supervised programmes for the promotion of motor abilities can help to limit motor deficits and prepare and support the integration of children into their peer group [19]. The special aims of such programmes are to develop individual perception of potential limitations and establish the boundaries of their exertional tolerance. In connection with acquiring age-appropriate knowledge about the disease-specific situation and the resulting symptom-limited capacity, this leads to a realistic self-estimation. In combination with this positive self-concept, emotional and psychosocial stability as well as a proper social integration, a realistic self-evaluation represents the most efficient protection from overload in daily life, physical activity and sport [19]. This is of special importance in adolescents with CHD since the specific behaviour patterns in youth often cause them to consciously disregard their body signals in order to avoid the ‘embarrassment’ a necessary physical break would bring about. By doing this, they expose themselves to potential danger. Prevention of this danger can – besides appeals to the adolescent’s rationality – only be achieved through an early stabilisation of personality and the improvement of self-responsibility and self-confidence.

Results of empirical studies show that the physical performance and motor skills of children and adolescents with CHD can be enhanced through regular engagement in autonomous or supervised physical activity [19, 25, 31, 35, 68–71]. These results also demonstrate that such participation not only improves physical performance (Fig. 13.9) and motor abilities but also positively influences the child’s emotional, psychosocial and cognitive development. The participation of 16 patients (aged 8–17 years) with complex congenital heart disease (11 Fontan patients and 5 with other CHD) in a 12-week exercise-based cardiac rehabilitation programme (1 h twice a week) revealed a significant improvement of exercise capacity. VO_2peak rose from 26.4 ± to 30.7 ± mL/kg per min and ventilatory anaerobic threshold from 26.4 ± to 30.7 ± mL/kg per min. No changes were seen in the control group. No rehabilitation-related complications or adverse effects were observed [69]. Both groups were reinvestigated 6.9 ± 1.6 months after competition of the programme, and the results demonstrate sustained improvements in not only exercise function but also self-esteem and emotional status in the rehabilitation group [68] (Fig. 13.10).

In 31 children with various types of CHD who participated in 8-month specific psychomotor training programme (75 min once a week), significant improvements in their motor performance were achieved. The number of children classified with deficits in motor performance decreased from 54.8 to 29.0 % [17] (Fig. 13.11). Figure 13.12 illustrates how possibly negative consequences of the disease can be compensated through the improvement of motor abilities and skills by special motor training programmes. In 61 children with single ventricle physiology after Fontan (aged 6–11 years) who participated in 24 months of home-based rehabilitation programme, motor gross skill improved significantly by 49 %. The level of moderate-to-vigorous physical activity increased significantly and was measured 36 ± 31 min/week above the baseline result at 24-month evaluation [25]. In a systematic review [31] of effects of physical exercise training programmes in CHD children and young adults, the results of 31 articles (621 subjects) were analysed. Eighteen studies reported on occurrence of adverse events, but none of them reported negative findings related to the exercise programme. Twenty-four studies (177 subjects) reported results on VO_2peak with mean increase of 2.6 ml/kg/min. Significant improvement in 6 min walking distance was reported in two studies. Muscle strength was assessed in five studies, showing significant improvement in strength mediated by the programme in three studies [31]. Tikkanen et al. [35] published a systematic review evaluating the results of cardiac rehabilitation in congenital heart disease in patients under 18 years of age. Sixteen studies met the inclusion criteria. These studies were of heterogeneous methodology and variable quality. Aerobic exercise training and resistance training were the core components of the exercise-based rehabilitation programmes. They found great differences in the exercise contents as well as exercise intensity, frequency and duration. While most of the older studies only included aerobic exercises, the more currently published studies included combined aerobic and resistance exercise programme. None of the studies reported adverse events. The optimal structure of an exercise-based paediatric cardiac rehabilitation programme remains unclear [35].