Background/Objectives: Today, digital technologies are integral to children’s lives; their increasing use, however, may raise health concerns. This study aims to examine the effect of screen time on physical activity and lifestyle factors in German school children. Methods: As part of the prospective hand-on-heart-study (“Hand-aufs-Herz”), a comprehensive cardiovascular system check-up examination was conducted on 922 German schoolchildren. The pupils were asked for a self-report on their daily physical activities and club sports. The examinations on-site contained measurements of the pupils’ weight and height as well as their physical fitness, which was assessed by a stair-climbing test. Results: A large proportion of pupils had a screen time of more than 2 h daily, regardless of the day of the week (63–76%). In fact, pupils with a screen time ≥ 2 h were more likely to achieve poor grades in school (weekday ORs 3.23, 95% CI 1.76, 5.95; weekend ORs 3.28, 95% CI 1.53, 7.00) and not be members of a sports club (weekday ORs 2.35, 95% CI 1.68, 3.29; weekend ORs 2.13, 95% CI 1.44, 3.14). Pupils who did not meet both recommendations for physical activity and screen time walked <5000 steps daily (60%), had a high proportion of overweight/obesity (40%), were non-swimmers (38.5%), spent ≥7 h sitting (35.8%), and slept fewer hours than recommended (30%). It has also been shown that longer screen time has a negative impact on the lifestyle of children and young people. Conclusions: Our results show that excessive screen time in children is linked to higher weight and an unhealthy lifestyle, increasing long-term cardiovascular risks. Public health initiatives aimed at reducing screen time, promoting physical activity, and encouraging healthier habits are essential to improve children’s overall health and prevent future chronic diseases.

Background/Objectives: Cardiorespiratory fitness (CRF) is of great interest in children and adolescents. Due to the limited availability of cardiopulmonary exercise testing, simple and reliable alternatives are needed. A stair climbing test (SCT) for the assessment of CRF developed at the Department of Pediatric Cardiology of the LMU University Hospital in Munich showed a strong correlation with VO₂max. The aim of this study is to prove its feasibility in a non-clinical setting and to analyse its results in a larger study population. Methods: During the “Hand aufs Herz” study, a comprehensive cardiovascular examination was carried out on 922 pupils and siblings (13.2 ± 7.8 years) at a high school in Bavaria. The SCT was performed to evaluate CRF: participants had to run up and down a total of four floors (14.8 m) as quickly as possible without skipping steps or holding on to the banister. Absolute time has been normalized over the standard height of 12 m to allow comparisons with different settings. An SCT Index was calculated to adjust results to the different weights of participants and the exact height of the staircase. Results: The SCT proved to be easily feasible and safe in non-clinical contexts. Out of 922 participants, 13 (1.4%) were not able to perform the test, and 3 (0.3%) had to interrupt it following fatigue or stumbling. A total of 827 participants aged from 9 to 17 years (13.1 ± 2.1 years, 45.8% girls) had a mean absolute SCT time of 53.4 ± 6.2 s and 43.3 ± 5.1 s when normalized over 12 m. Conclusions: The SCT represents a simple, cost- and time-saving test that allows a rapid and solid assessment of cardiorespiratory fitness in children and adolescents. We could demonstrate that it is safe and feasible in non-clinical contexts. Its short duration and universal applicability are valuable advantages that could facilitate the establishment of a repetitive cardiovascular screening in the pediatric population, particularly in outpatient departments or settings with low-resource systems.

Background/Objectives: physical activity (PA) in children offers lifelong benefits, yet nearly four in five children are insufficiently active. We examined sex-specific differences in sport participation by sport type and its association with weight status. Methods: in the ongoing hand-on-heart-study (“Hand-aufs-Herz”), comprehensive data on sociodemographic profiles, PA, and anthropometry were collected from 922 school-aged children, adolescents, and young adults (8–20 years) in Germany. Sex-specific differences in sport participation, sport types, and weight status were analyzed using descriptive statistics and logistic regression models. Results: based on the eligibility criteria for analysis (ages 8–18 years), 883 pupils were included (mean age 13.1 ± 2.4 years), 406 (46%) were females. Compared to females, males had a 43% higher chance of being members of a sports club and were more likely to spend more days/week on sports (44–85%). Males participated more in football, martial arts, and basketball while females favored gymnastics and volleyball. As age increased, males had a 30% higher likelihood of not being sports club members (females: 13%). Overweight/obese males had twice the risk of lacking sports memberships. The largest body mass index (BMI) difference was found in males and females participating in athletics, with −4.64 kg/m² (males) and −1.99 kg/m² (females) compared to their counterparts without club memberships. Conclusions: in conclusion, sports participation should be encouraged especially among females and overweight/obese males. Targeted strategies should focus on promoting inclusive and non-competitive activities that cater to their interests.