At the beginning of 2020, the World Health Organization, UNICEF and The Lancet published a report entitled to Future for The World's Children? in which it was concluded that the health and future of children and adolescents around the world is in danger from climate change and other threats such as the increase in ultra -processed food consumption, sugary drinks, alcohol and tobacco (1). However, a current problem that is not addressed in the document and that also supposes a real danger to their present and future health is the lack of physical activity carried out at these ages, since 80% of young people around the world do not It meets the minimum amount of recommended physical activity (2).

Performing physical activity from an early age can impact the health of the following years. This has stated a study published in the Pediatrics that evaluated the level of physical activity of more than 400 children between 3 and 5 years and made a re-evaluation 3 years later measuring different cardiovascular health markers such as cardiorespiratory capacity (CRF , for its acronym in English), blood pressure and arterial stiffness (3). The remarkable thing about the study was that the children who carried out more physical activity during those first years of life showed better cardiovascular health indicators within a few years, obtaining greater benefits with vigorous physical activity (3). We observe, therefore, that the protective effect of physical activity on cardiovascular health begins from a very early stage of life.

Current cardiorespiratory capacity and future health

In children and adolescents, the CRF - which depends large Mortality risk years later (6–10). Thus, in an important multicenter study in which several Spanish centers participated, the authors observed that the CRF that a child of 6 to 10 years has determined its cardiovascular risk two years later (7). They also determined the CRF cutting points for good cardiovascular health, establishing them at 39.0 ml/kg/min for boys and 37.5 ml/kg/min for girls. In addition, a systematic review published in the prestigious Sports Medicine showed that having a good CRF during childhood and adolescence is associated with a lower body mass index, grozship and body fat circumference and lower prevalence of metabolic syndrome 6 years later, what that gives a cardioprotective role to the CRF that we have of children about our future health (8). But this role seems to stay even after many years. This is what follows from a meta-analysis published in the prestigious Jama Pediatrics and led by our partner Dr. Antonio García Hermoso (9). In this case, the meta-analysis included 55 studies, more than 37,000 young people between 3 and 18 years old, and a follow-up of between 1 and 27 years. The results confirmed that a good CRF during childhood and adolescence is associated with a lower risk of developing obesity and heart disease in the future (9). And in the same way as the CRF, another component of the physical condition - although less studied - as the force has also shown a great influence on our health and the risk of mortality years later (6,11,12).

Physical form and risk of early retirement

While the relationship between the CRF we have of children or adolescents and our subsequent health has been widely demonstrated, little was so far known about the role of the CRF and its association with disabling diseases that derive in an early retirement. However, in recent years different prospective studies led by Dr. Francisco B. Ortega of the University of Granada and researchers at Karolinska Institute (Stockholm, Sweden) have been published, in which the physical condition data of more of one million Swedish teenagers (between 16 and 19 years old) during recruitment exams prior to military service and were followed for an average of 28 years. The authors found that having a low CRF or combining a low CRF with low levels of muscle strength or obesity during adolescence was an important risk factor for early retire of psychiatric, musculoskeletal or cardiovascular diseases) (13–15). Another of the results to highlight is that a good CRF during adolescence, regardless of the body mass index, was associated with a lower risk of early retirement due to disabling disease (14). That is, adolescents with obesity and a good CRF had a lower risk of disability in the future than adolescents with Normapeso, but with a low physical condition. 

In addition, in an editorial that has just been published in British Journal of Sports Medicine, Dr. Ortega and his collaborators have estimated that the attributable population risk (the PAF, for its acronym in English, which indicates the events that would be avoided if a Determined risk factor was not present; 14% if teenagers with low CRF were form (16). And if we divided the CRF into deciles, the PAF would be 10% if the youth of the deciles 1 to 9 increased their CRF corresponding to 1 decil, for example, that they pass from the 50th percentile to the 60s ( Figure 1 ). The PAF estimated by the increase in CRF was relatively high for all specific causes of disabling disease, indicating that many cases of disability could have been prevented from having been better physical. Therefore, these data indicate that an improvement of 1 decil in the CRF would be associated with a 10% decrease in disabling diseases (16).

Figure 1 . Population attributable risk (PAF) for disability due to different causes associated with cardiorespiratory capacity (16).

Conclusions

These findings have notable implications for public health, since they support the importance of a good CRF during childhood and adolescence to prevent subsequent chronic diseases. That is why the promotion of active lifestyles becomes essential, as well as the acquisition of a good physical condition from the earliest stages of life that can help preserve present and future health. If, in addition, we take into account the difficulty of modifying habits during adulthood, we can say without fear of being wrong that childhood and adolescence are key periods in the future of health that young people have when they are older.

References: 

1. Clark H, Coll-Seck Am, Banerjee A, Peterson S, Dalglysh SL, America S, et al. Future for the World's Children? To who - unicef ​​- lancet commission. Lancet 2020; 395 (10224): 605–58. 

2. Guthold R, Stevens Ga, Riley LM, Bull FC. Global Trends in insufficient Physical Activity Among Adolescents: A Poold Analysis of 298 Population-Based Surveys with 1 · 6 million participants. Lancet Child teen heal. 2020; 4 (1): 23–35. 

3. Prudfoot Na, King-Dowling S, Cairney J, Bray Sr, Macdonald MJ, Timmons bw. Physical Activity and Trajectories of Cardiovascular Health Indicators During Early Childhood. Pediatrics 2019; 144 (1). 

4. Ortega FB, Ruiz JR, MJ Castillo, Sjöström M. Physical Fitness in Childhood and Adolescence: A Powerful Marker of Health. Int j obes. 2008; 32 (1): 1–11. 

5. Ruiz Jr, Cavero-Redondo I, Ortega FB, Welk GJ, Andersen LB, Martinez-Vizcaino V. CardiorespiRary Fitness Cut Points to Avoid Cardiovascular Disease Risk in Children and Adolescents; What Level of Fitness Should Raise A Red Flag? A Systematic Review and Meta-Analysis. BR J Sports Med. 2016; 50 (23): 1451–8. 

6. Ruiz Jr, Castro-Piñero J, Artero EG, Ortega FB, Sjöström M, Suni J, et al. Predictive Valridity of Health-Related Fitness in Youth: A Systematic Review. Br J Sports Med. 2009; 43 (12): 909–23. 

7. Castro-Piñero J, Perez-Bey A, Segura-Jiménez V, Aparicio Va, Gómez-Martínez S, Izquierdo-Gomez R, et al. Cardiorespiratory Fitness Cutoff Points for Early Detection of present and cardiovascular future risk in Children: 2-YEAR FOLLOW-UP STUDY. MAY CLIN PROC. 2017; 92 (12): 1753–62. 

8. MINTJENS S, Ment MD, DAAMS JG, VAN POPPEL MNM, ROSEEBOOM TJ, GEMKE RJBJ. Cardiorespiratory Fitness in Childhood and Adolescence Affects Future Cardiovascular Risk Factors: A Systematic Review of Longitudinal Studies. Sport Med. 2018; 48 (11): 2577–605. 

9. GARCIÁ-HERMOSO A, RAMÍREZ-VÉLEZ R, GARCIÁ-ALONSO Y, ALONSO-MARTÍNEZ AM, IZQUIERDO M. Association of CardiorespiRATORY FITNESS LEVELS DASING DURING YOUTH WITH HEALTH HEALTH RISK LATER IN LIFE: A SYSTEMATIC REVIEW AND META-ANALYSIS. Jama Pediatr. 2020; 174 (10): 952–60.

10. Sato M, Kodama S, Sugawara A, Saito K, Sone H. Physical Fitness During Adolescence and Adult Mortality. 2009; 20 (3): 463–4.

11. García-Hermoso A, Ramírez-Campillo R, Izquierdo M. is muscular fitness associated with future Health Benefits in Children and Adolescents? A Systematic Review and Meta-Analysis of Longitudinal Studies. Sport Med. 2019; 49 (7): 1079–94. 

12. Ortega FB, Silventoinen K, Tynelius P, Rasmussen F. muscular Strength in Male Adolescents and Premature Death: Cohort Study of One Million Participants. BMJ. 2012; 345 (7884). 

13. Henriksson H, Henriksson P, Tynelius P, Ortega FB. Muscle Weakness in Adolescence is Associated with Disability 30 Years Later: A Population-Based Cohort Study of 1.2 Million Men. BR J Sports Med. 2019; 53 (19): 1221–30. 

14. Henriksson P, Henriksson H, Tynelius P, Berglind D, Löf M, Lee Im, et al. Fitness and Body Mass Index During Adolescence and Disability Later in Life. Ann Intern Med. 2019; 170 (4): 230–9. 

15. Henriksson H, Henriksson P, Tynelius P, Ekstedt M, Berglind D, Labayen I, et al. Cardiorespiratory Fitness, muscle Strength, and Obesity in Adolescence and Later Chronic Disability Due To Cardiovascular Disease: A Cohort Study of 1 Million Men. Eur Heart J. 2020; 41 (15): 1503–10. 

16. Henriksson P, Shiroma Ex, Henriksson H, Tynelius P, Berglind D, Löf M, Lee Im, Ortega FB. Fit for life? Low CardiorespiRary Fitness in Adolescence is Associated with a Higher Burden of Future Disability. Br J Sports Med. 2021; 55 (3): 128-129.