Ability of preschoolers to achieve maximal exercise and its correlation with oxygen uptake efficiency slope ∼ an observational study by direct cardiopulmonary exercise testing

Sports Physiology in Adolescent Track-and-Field Athletes: A Narrative Review

The present study aimed to review the physiological aspects of adolescent track-and-field (TAF) athletes. A search of Scopus on 27/12/2022 using the syntax ABS (track-and-field) AND ABS (children) OR ABS (adolescent) showed 121 documents, and 45 were considered for further analysis. In addition, handsearching was conducted to identify Russian literature missing in Scopus. Differences were shown in performance characteristics among disciplines, especially between throwers and the other athletes. The sex difference in performance (ie, a better performance in boys than in girls) started in early adolescence. A relative age effect was more pronounced in athletes under 13 years old. Despite the wide use of nutritional supplements, an insufficient intake of vitamins has been found. The age of training onset and body weight were identified as risk factors for problems with menarche. The inclusion of track-and-field training programs in physical education was beneficial for health and physical fitness. The need to collaborate closely with parents and coaches was identified, especially, regarding education in topics such as the age of training onset, relative age effect, and doping. In conclusion, the existence of many disciplines with different anthropometric and physiological characteristics highlighted the need for a discipline-specific approach.

The Omni Scale Is Not Suitable for Assessing Self-Perceived Exertion during Physical Activity in Preschoolers

INTRODUCTION

We aimed to identify the utility, reliability, and validity of an adapted version of the OMNI self-perceived exertion (PE) rating scale in preschoolers.

POPULATION AND METHODS

Firstly, 50 (mean age ± standard deviation [SD] = 5.3 ± 0.5 years, 40% girls) performed a cardiorespiratory fitness (CRF) test twice, with a one-week interval between assessments, and rated their PE either individually or in groups. Secondly, 69 children (mean age ± SD = 4.5 ± 0.5 years, 49% girls) performed two CRF tests, separated by a one-week interval, twice and rated their self-PE. Thirdly, the heart rate (HR) of 147 children (mean age ± SD = 5.0 ± 0.6 years, 47% girls) were compared against self-rated PE after finishing the CRF test.

RESULTS

Self-assessed PE differed when the scale was administered individually (e.g., 82% rated PE with 10) or in groups (42% rated PE with 10). The scale showed poor test-retest reliability (ICC:0.314-0.031). No significant associations were found between the HR and PE ratings.

CONCLUSIONS

An adapted version of the OMNI scale was found not suitable for assessing self-PE in preschoolers.

Cardiopulmonary Fitness of Preschoolers with Congenital Heart Disease: An Observational Study

With advancements in cardiopulmonary rehabilitation over the past few decades, the survival rate of patients with congenital heart disease (CHD) has increased. However, the Cardiopulmonary fitness (CPF) of these patients is poor. Here, we aimed to investigate CPF in preschoolers with CHD (aged 4 to 6 years) using cardiopulmonary exercise testing. We retrospectively compared 102 healthy preschoolers with 80 preschoolers with CHD. The latter had lower peak oxygen consumption, oxygen consumption at anaerobic threshold and metabolic equivalent at anaerobic threshold. The same result was observed in boys with CHD, but not in girls, when sex was sub-analyzed. Considering the body composition, children with CHD had a lower fat-free mass index (FFMI) than their healthy peers. Healthy preschoolers with a normal body mass index (BMI) had higher anaerobic threshold and peak metabolic equivalent values than overweight or underweight children. This was categorized under the BMI reference of the Ministry of Health and Welfare in Taiwan. In conclusion, the CPF difference between the CHD and healthy groups was identified as early as in preschool age, and better CPF in healthy preschoolers within the normal BMI range suggests the importance of weight control in young children.

New kids on the CPET: age-appropriate outdoor cardiopulmonary exercise testing in preschoolers

Purpose

Cardiopulmonary exercise testing (CPET) in preschoolers (4–6 years) represents a challenge. Most studies investigating CPET have been limited to older children (> 8 year). However, knowledge of the performance of small children is essential for evaluating their cardiorespiratory fitness. This study strives to compare a modified Bruce protocol with a new age-appropriate incremental CPET during natural movement running outdoors, using a mobile device.

Methods

A group of 22 4–6-year-old healthy children was tested indoor on a treadmill (TM) using the modified Bruce protocol. The results were compared with a self-paced incremental running test, using a mobile CPET device in an outdoor park. The speeds were described as (1) slow walking, (2) slow running, (3) regular running, and (4) running with full speed as long as possible.

Results

Mean exercise time outdoors (6,57 min) was significantly shorter than on the treadmill (11,20 min), \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}{O}_{2peak}$$\end{document}V˙O2peak (51.1 ml/min/kg vs. 40.1 ml/min/kg), RER (1.1 vs. 0.98) and important CPET parameters such as \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\dot{V}E$$\end{document}V˙E_max, O₂pulse, heart rate and breath rate were significantly higher outdoors. The submaximal parameter OUES was comparable between both the tests.

Conclusions

Testing very young children with a mobile device is a new alternative to treadmill testing. With a significantly shorter test duration, significantly higher values for almost all cardiopulmonary variables can be achieved without losing the ability to determine VT1 and VT2. It avoids common treadmill problems and allows for individualized exercise testing. The aim is to standardize exercise times with individual protocols instead of standardizing protocols with individual exercise times, allowing for better comparability.

Comparison of cardiorespiratory fitness between preschool children with normal and excess body adipose ~ An observational study

Objective

Overweight and obesity in preschoolers might develop into childhood and even adulthood obesity. Overweight and obesity have been shown to be negatively related with cardiorespiratory fitness (CRF) in children and adults but few studies did among preschoolers. We aimed to evaluate whether excess body adipose is negatively associated with CRF in both the submaximal and maximal effort of preschool children in exercise testing and to examine if there is difference to achieve maximal effort during exercise testing between preschoolers with normal and excess body adipose.

Methods

Data of 106 preschoolers aged 4–6 that received symptom-limited treadmill exercise testing was analyzed. Anthropometry was measured by vector bioelectrical impedance analysis. Excess body adipose was defined as (1) ‘overweight’ and ‘obesity’ by body mass index (BMI), (2) fat mass index (FMI) greater than the sex- and age-specific 75th percentile of whole subjects, and (3) fat-free mass index (FFMI) smaller than the sex- and age-specific 25th percentile. CRF was indicated by metabolic equivalent (MET) at anaerobic threshold (AT MET), peak MET, oxygen uptake efficiency slope (OUES) calculated by the 50% (OUES-50) and the entire (OUES-100) duration of the exercise testing.

Results

Preschoolers with excess body adipose by three different definitions (BMI, FMI, and FFMI) all had poorer ability to perform maximal effort (p = 0.004, 0.043, and 0.007, respectively). Preschoolers with excess body adipose by BMI and FFMI classifications had lower OUES-50 (p = 0.018, and 0.001, respectively), and lower OUES-100 (p = 0.004, and 0.001, respectively) than peers with normal body adipose during exercise testing while those with excess body adipose by FMI classification showed no significant differences from peers with normal body adipose in both OUES-50 and OUES-100.

Conclusions

Preschoolers with excess body adipose had lower CRF significantly during treadmill exercise testing. Weight control and health promotion should start as early as possible.