Cardiovascular magnetic resonance assessment of left atrial size and function in endurance athletes.

Background: Left atrial (LA) dilatation is linked to cardiovascular disease and atrial fibrillation but its associations in athletes are unknown. The authors investigated whether aerobic fitness and clinical parameters are associated with LA dilatation and emptying fraction (EF) in endurance athletes. Materials & methods: 65 endurance athletes underwent cardiovascular magnetic resonance to assess LA size and function along with fitness assessment. 25 sedentary controls underwent an identical cardiovascular magnetic resonance protocol. Results: In athletes, LA volume index was elevated, while total and passive LAEFs were decreased versus sedentary controls. Increasing age and maximal oxygen uptake were associated with LA volume index. Only older age was associated with decreased total LAEF. Conclusion: LA dilatation in athletes is associated with increasing age and aerobic fitness rather than conventional cardiovascular risk factors.

Screen time and physical activity behaviours are associated with health-related quality of life in Australian adolescents.

PURPOSE: To explore the cross-sectional relationships between health-related quality of life (HRQoL) and physical activity (PA) behaviours and screen-based media (SBM) use among a sample of Australian adolescents. METHODS: Data came from baseline measures collected for the It's Your Move! community-based obesity prevention intervention. Questionnaire data on sociodemographics, PA, SBM and HRQoL were collected from 3,040 students (56% boys) aged 11-18 years in grade levels 7-11 in 12 secondary schools. Anthropometric data were measured. RESULTS: The highest level of PA at recess, lunchtime and after school was associated with higher HRQoL scores (boys, by 5.3, 8.1, 6.3 points; girls, by 4.2, 6.1, 8.2 points) compared with not being active during these periods. Exceeding 2 h of SBM use each day was associated with significantly lower HRQoL scores (boys, by 3.2 points; girls, by 4.0 points). Adolescents who were physically active and low SBM users on school days had higher HRQoL scores (boys, by 6.6 points; girls, by 7.8 points) compared with those who were not physically active every school day and high SBM users on school days. CONCLUSIONS: Several of the relationships between low PA and high SBM use and HRQoL were comparable to those previously observed between chronic disease conditions and HRQoL, indicating that these behaviours deserve substantial attention.