Response To Exercise In Children Research Articles

Exercise responses in children and adults with a Fontan circulation at simulated altitude.

BackgroundTraveling to high altitude has become more popular. High‐altitude exposure causes hypobaric hypoxia. Exposure to acute high altitude, during air travel or mountain stays, seems to be safe for most patients with congenital heart disorders (CHD). Still, current guidelines for CHD patients express concerns regarding safety of altitude exposure for patients with a Fontan circulation. Therefore, investigating hemodynamic and pulmonary responses of acute high‐altitude exposure (±2500 m) at rest and during maximal exercise in patients with Fontan circulation can provide clarity in this dispute and may contribute to improvement of clinical counseling.MethodsTwenty‐one Fontan patients with 21 age‐matched healthy controls, aged 8‐40 years, were enrolled in an observational study. Participants performed two cardiopulmonary exercise tests on a cycle ergometer with breath‐by‐breath respiratory gas analyses combined with noninvasive impedance cardiac output measurements: one at sea level (±6 m) and one at simulated high altitude (±2500 m), respectively.ResultsThe effect of altitude exposure was different in rest for saturation (−2.3% vs −4.1%) between Fontan patients and healthy controls (P < .05). At peak exercise the effects of high altitude exposure was different on VO2 (−5.1% vs 9.6%) and AvO2‐diff (−0.3% vs −12.8%) between Fontan patients and healthy controls.ConclusionAlthough, acute high‐altitude exposure has a detrimental effect on exercise capacity, the impact on pulmonary and hemodynamic responses of high‐altitude exposure is comparable between Fontan patients and healthy controls.

The Effect of Acute Exercise on Neutrophil Reactive Oxygen Species Production and Inflammatory Markers in Healthy Prepubertal and Adult Males.

The adaptive effects of exercise-induced inflammation and reactive oxygen species production has been well studied in adults, but not in children. Characterizing the exercise responses in children compared with adults will start clarifying the transition from the child phenotype to that of an adult. Ten children aged 8-10 and 12 adults aged 19-21 performed 2 × 30-min bouts of continuous cycling, separated by a 6-min rest period, at a target work rate of 60% of their maximum aerobic capacity. Blood samples were collected pre- and immediately postexercise, and analyzed for neutrophil count, systemic oxidative and inflammatory markers, and intracellular neutrophil-derived reactive oxygen species. Although postexercise absolute neutrophils increased by approximately twofold in men (2.72 ± 0.49 × 109/L to 4.85 ± 2.05 × 109/L; p = .007), boys showed no such change (3.18 ± 0.67 × 109/L to 3.57 ± 0.73 × 109/L; p = .52). Contrary to these findings, boys did show an increase in overall intracellular neutrophil ROS production, whereas men did not. Boys also demonstrated higher overall protein carbonyl levels (0.07 nmol/mg vs 0.04 nmol/mg; boys vs men respectively), whereas men showed higher overall malondialdehyde (0.24 μM vs 0.67 μM; boys vs men respectively). The differences observed in the exercise-induced inflammatory and oxidative stress response may indicate growth-mediated adaptive responses to exercise during childhood development.

Effects of obstructive sleep apnea and obesity on exercise function in children.

Evaluate the relative contributions of weight status and obstructive sleep apnea (OSA) to cardiopulmonary exercise responses in children. Prospective, cross-sectional study. Participants underwent anthropometric measurements, overnight polysomnography, spirometry, cardiopulmonary exercise function testing on a cycle ergometer, and cardiac doppler imaging. OSA was defined as ≥ 1 obstructive apnea or hypopnea per hour of sleep (OAHI). The effect of OSA on exercise function was evaluated after the parameters were corrected for body mass index (BMI) z-scores. Similarly, the effect of obesity on exercise function was examined when the variables were adjusted for OAHI. Tertiary pediatric hospital. Healthy weight and obese children, aged 7-12 y. N/A. Seventy-one children were studied. In comparison with weight-matched children without OSA, children with OSA had a lower cardiac output, stroke volume index, heart rate, and oxygen consumption (VO2 peak) at peak exercise capacity. After adjusting for BMI z-score, children with OSA had 1.5 L/min (95% confidence interval -2.3 to -0.6 L/min; P = 0.001) lower cardiac output at peak exercise capacity, but minute ventilation and ventilatory responses to exercise were not affected. Obesity was only associated with physical deconditioning. Cardiac dysfunction was associated with the frequency of respiratory-related arousals, the severity of hypoxia, and heart rate during sleep. Children with OSA are exercise limited due to a reduced cardiac output and VO2 peak at peak exercise capacity, independent of their weight status. Comorbid OSA can further decrease exercise performance in obese children.

Maximal Aerobic and Anaerobic Exercise Responses in Children with Cerebral Palsy

The objective of this study is to compare the maximal aerobic and anaerobic exercise responses of children with cerebral palsy (CP) by level of motor impairment and in comparison with those of typically developing children (TD). Seventy children with CP, with varying levels of motor impairment (Gross Motor Function Classification System (GMFCS) I-III), and 31 TD performed an incremental continuous maximal aerobic exercise test and a 20-s anaerobic Wingate test on a cycle ergometer. Peak oxygen uptake (V˙O2peak), anaerobic threshold (AT), peak ventilation (V˙Epeak), peak oxygen pulse (peak O2 pulse), peak ventilatory equivalent of oxygen (peak V˙E/V˙O2) and carbon dioxide (peak V˙E/V˙CO2), peak aerobic power output (POpeak), and mean anaerobic power (P20mean) were measured. Isometric leg muscle strength was determined as a secondary outcome. Analysis revealed a lower V˙O2peak for CP (I: 35.5 ± 1.2 (SE); II: 33.9 ± 1.6; III: 29.3 ± 2.5 mL·kg-1·min-1) compared with TD (41.0 ± 1.3, P < 0.001) and a similar effect for AT (I: 19.4 ± 0.9; II: 19.2 ± 1.2; III: 15.5 ± 1.9; TD: 24.1 ± 1.0 mL·kg-1·min-1, P < 0.001). V˙Epeak and peak O2 pulse were also lower, whereas peak V˙E/V˙CO2 was higher in CP compared with TD (P < 0.05) and peak V˙E/V˙O2 similar between groups. All these variables showed no differences for different motor impairment levels. POpeak was lower for CP (I: 2.4 ± 0.1; II: 1.8 ± 0.1; III: 1.4 ± 0.2 W·kg-1) versus TD (3.0 ± 0.1, P < 0.001), together with a lower P20mean in CP (I: 4.6 ± 0.2; II: 3.3 ± 0.2; III: 2.5 ± 0.4 W·kg-1) versus TD (6.4 ± 0.2, P < 0.001), and both decreased significantly with increasing motor impairment. Children with CP have decreased aerobic and anaerobic exercise responses, but decreases in respiratory and aerobic exercise responses were not as severe as predicted by motor impairment. Future research should reveal the role of inactivity on the exercise responses of children with CP and possibilities for improvement through training interventions.

Exercise capacity of children with pediatric lung disease

Pulmonary function of children with cystic fibrosis (CF) and bronchopulmonary dysplasia (BPD) is similar at rest even though the mechanisms of injury differ. We sought to compare the peak exercise responses in children with BPD versus CF while controlling for pulmonary impairment, nutritional status, gender, age, height, and predicted forced expired volume in 1 second (approximately 73% of predicted). Nine BPD children and 9 CF children underwent spirometry and a progressive exercise test to maximum on a cycle ergometer. There was no difference between groups in body mass percentile (CF:97 +/- 13%, BPD: 98 +/- 11%), peak power output (Wpeak) (CF:67 +/- 19 W, BPD:73 +/- 28 W), % predicted Wpeak (CF:83 +/- 28%, BPD:88 +/- 15%), peak oxygen uptake (VO2peak, CF: 38 +/- 7 ml/kg/min, BPD: 39 +/-6 ml/kg/min), or % predicted VO2peak (CF:99 +/- 16 %, BPD:96 +/- 27%). Children with mild pulmonary impairments are able to achieve a near normal peak power output and a normal VO2peak. Neither the aetiology nor the developmental onset of the process appears to be important influences on VO2peak or Wpeak.

Effect Of Caffeine On Metabolic And Cardiovascular Responses To Submaximal Exercise

Few studies have investigated the effect of caffeine on exercise responses in children. No study has compared the effects of caffeine on exercise responses between children versus adults. PURPOSE Compare the effects of caffeine on physiological responses to exercise between young boys versus college age men. METHODS Twenty-six 7–9 year old boys and eighteen 18–25 year old men participated in a double-blind, double-crossover placebo study. Subjects received in random order twice each, either a placebo drink (cherry flavored Sprite®-PL) or drink plus anhydrous caffeine (5 mg/kg body mass, CAF). Following a 60-minute absorption period children rode at 25 W and then 50 W while men rode at 50 W and then 60% VO2 max for 8 minutes each on an electronically braked ergometer while heart rate (HR), oxygen consumption (VO2), and respiratory exchange ratio (RER) were monitored continuously, and blood pressure (BP) was measured every two minutes. RESULTS HR was significantly lower (p < 0.05) at 25 W (119±10 vs 126±9 bpm) and 50 W in boys (150±15 vs 157±13 bpm) in CAF vs. PL, respectively. In men HR was the same at both 50 W (107±17 vs. 106±16 bpm) and 60% VO2 max (146±8 vs. 146±10 bpm) in CAF vs. PL, respectively. Systolic BP(SBP) was higher at 25 W (132±12 vs 128±12 mmHg, p < 0.05) and 50 W in boys (147±14 vs 144±14 mmHg, p = 0.067) in CAF vs. PL, respectively. Diastolic BP (DBP) was higher at 25 W (71±8 vs 68±8 mmHg, p < 0.05) and 50 W in boys (73±9 vs 70±9 mmHg, p < 0.05) in CAF vs PL, respectively. Blood pressure in men was always higher in CAF vs. PL but never reached statistical significance. Specifically, SBP was similar at 50 W (161±16 vs 159±15 mmHg, p = 0.685) and 60% VO2 max (200±20 vs 198±21 mmHg, p = 0.245) in CAF vs. PL, respectively. Diastolic BP was similar at 50 W (79±11 vs 76±8 mmHg, p = 0.058) and 60% VO2 max (84±12 vs 83±8 mmHg, p = 0.559) in CAF vs. PL, respectively. Both VO2 and RER were the same at both 25 W and 50 W in boys, and 50 W and 60% VO2 max in men in CAF vs PL. CONCLUSIONS Caffeine (5 mg/kg) has a similar effect on metabolic responses to exercise in boys and men. The same dose causes a significant elevation in exercise BP and decrease in HR in boys while in men there was only a trend for a similar change in BP (although not significant) with no change in HR.

1152-205 Exercise responses in children with pulmonary hypertension

1152-205 Exercise responses in children with pulmonary hypertension

Relationship between pulmonary function, O2 saturation during sleep and exercise, and exercise responses in children with cystic fibrosis.

Relationship between pulmonary function, O2 saturation during sleep and exercise, and exercise responses in children with cystic fibrosis.

Exercise responses in children with progressive aortic regurgitation

Exercise responses in children with progressive aortic regurgitation