Study On The Variation Characteristics And Limiting Factors Of Aerobic Capacity Of Youth Athletes In Different Age

Objective:Aerobic capacity can comprehensively reflect the body's ability to uptake,transport and utilize oxygen.It is related to the heart's blood pumping function,lung ventilation function,the ability of the blood circulation system to carry oxygen and the ability of peripheral tissues such as muscles to utilize oxygen.Besides the impact on health,aerobic capacity is also an important determinant for the success of many sports.Aerobic capacity is not only the decisive factor for athletes in endurance sports to achieve excellent performance,but also one of the important factors for athletes in fighting sports and team games to win competitions.Most of the current data involving aerobic capacity in children and adolescents is based on individuals not participating in intensive training programs,and with the vast majority of studies measuring the duration of training interventions on a monthly basis,it is unclear how years of systematic athletic training will affect the aerobic capacity of youth athletes.Additionally,it has been suggested that youth athletes in different sports show different patterns of aerobic capacity development as they age.Based on this,the following hypotheses are proposed to be experimentally validated in this study:1)differences in age-dependent characteristics of aerobic capacity in youth athletes of different genders;2)differences in age-dependent characteristics of aerobic capacity in youth athletes of different sports;and 3)differences in physiological factors that limit the development of aerobic capacity in youth athletes of different age groups.Based on the validation of the above hypothesis,the characteristics of changes in aerobic capacity of adolescent athletes aged 11-18 years in different sports were explored,and the physiological factors limiting the aerobic capacity of adolescent athletes of different ages were investigated in terms of the uptake,transport and utilization of oxygen in the body.Method:This study selected 585 youth athletes aged 11-18?386 boys and 199 girls?as research participants.According to the energy metabolism characteristics of sports,they are divided into the aerobic group?swimming,middle and long-distance running,sailing,cycling,rowing,and canoeing?and the mixed-aerobic group?football,basketball,judo,boxing,Sanda,taekwondo?.Their peak oxygen uptake?VO₂peak?is tested by ramp type incremental load exercise.Taking age,gender and sports as independent variables and VO₂peak as dependent variables,a Three-Way ANOVA was conducted to observe the characteristics of aerobic capacity of young athletes with age.By testing lung function indicators,heart structure and function indicators,and muscle oxygen utilization indicators,the possible mechanism of restricting aerobic capacity development of youth athletes of different ages is analyzed from three aspects of body oxygen uptake indicators,oxygen transportation indicators,and oxygen utilization indicators.Taking age,gender,and sports as independent variables,taking oxygen uptake,oxygen transportation,and oxygen utilization as dependent variables respectively,a Three-Way MANOVA was conducted to observe the differences between age,gender and sports events of various physiological indicators.After the principal components were extracted from oxygen uptake indicators,oxygen transportation indicators,and oxygen utilization indicators by factor analysis,the extracted principal components were taken as independent variables and VO₂peak as dependent variables for multiple regression analysis to explore the possible physiological mechanisms affecting the aerobic capacity of youth athletes.Results:Through Three-Way ANOVA,it was found that VO₂peak of 11-18-year-old youth athletes increased with age.Male athletes VO₂peak was significantly higher than female athletes,p<0.001?95%CI:0.649,0.804?.Before the age of 18,the peak of VO₂peak for male youth athletes has been growing rapidly,with the fastest growth rate appearing in 12-14 years old.On the other hand,the growth rate of VO₂peak for female youth athletes is relatively slow before the age of 15,and it increases rapidly after the age of 15,with the fastest growth rate occurring between the ages of 16-18 years old.VO₂peak was significantly higher in aerobic athletes than in mixed-aerobic athletes,p<0.001?95%CI:0.297,0.452?,with VO₂peak continuing to increase until age 18,with the fastest increase occurring in the 12-15 age range;and mixed aerobic athletes continued to increase until age 16,then stabilized,with the fastest increase occurring in the 12-14 age range.Through factor analysis and multiple regression analysis,we found that that the limiting factors of VO₂peak for youth athletes aged 11-13 are mainly lung function and heart structure,with R² adjusted to 0.221.The limiting factors of VO₂peak for 14-15-year-old youth athletes are mainly heart structure,cardiac function,and lung function,with R² adjusted to 0.393.The limiting factors of VO₂peak for 16-18-year-old youth athletes are mainly cardiac structure,muscle oxygen utilization capacity,lung function,cardiac functional capacity,and diastolic capacity,with R² adjusted to 0.554.The limiting factors of male youth athletes VO₂peak are heart structure,cardiac function,SmO₂index,lung function,and tHb index in order of contribution,with R² adjusted to 0.369.The limiting factors of female youth athletes VO₂peak are mainly heart structure,cardiac function,and lung function,with R² adjusted to 0.238.The limiting factors of VO₂peak for youth athletes in aerobic sports are heart structure,tHb indicators,diastolic function,lung function,SmO₂ indicators,and cardiac function,with R² adjusted to0.570.The limiting factors of VO₂peak for youth athletes in mixed-aerobic sports are mainly tHb index,heart structure,and lung function,with R² adjusted to 0.277.Conclusion:1.The characteristics of aerobic capacity of youth athletes of different genders vary with age.The aerobic capacity of male athletes is significantly higher than that of female athletes.The VO₂peak of male youth athletes has maintained rapid growth before the age of 18,with the fastest growth rate appearing at the age of 12-14;the VO₂peak of female youth athletes grew slowly before the age of 15,and grew rapidly after the age of 15,with the fastest growth rate occurring between 16-18.2.The characteristics of aerobic capacity were inconsistent with age between athletes in different sports,and aerobic capacity was significantly higher in aerobic than in mixed-aerobic sports.The VO₂peak in aerobic athletes continues to grow until age 18,with the fastest growth rate occurring at age 12-15;while VO₂peak in mixed-aerobic athletes continues to grow until age 16 and then plateaus,with the fastest growth rate occurring at age 12-14.3.The limiting factors for aerobic capacity vary by age,and age differences in aerobic capacity in youth athletes are driven by growth and development and sports training caused by a combination of the two.The limiting factors of VO₂peak for youth athletes aged 11-13 are mainly oxygen uptake index?lung function?and oxygen transport index?heart structure?;The limiting factors of VO₂peak for 14-15 year-old athletes are mainly oxygen uptake index?lung function?and oxygen transport index?cardiac structure and cardiac contraction?;The limiting factors of VO₂peak for 16-18 year-old young athletes are mainly oxygen uptake capacity?lung function?,oxygen transport capacity?cardiac structure,cardiac contraction and diastole?and oxygen utilization index?SmO₂,tHb and BLA?.The effect of oxygen utilization index on VO₂peak of youth athletes aged11-13 years and 14-15 years is not statistically significant.4.The limiting factors for aerobic capacity of youth athletes in different sports are different,and muscle oxygen utilization capacity is the main factor for the difference of VO₂peak among young athletes of different genders.The main limiting factors of male adolescent athletes VO₂peak are oxygen uptake capacity?lung function?,oxygen transport capacity?heart structure,cardiac contraction?and oxygen utilization capacity index?SmO₂,tHb?,while the main limiting factors of female adolescent athletes VO₂peak are oxygen uptake capacity index?lung function?and oxygen transport capacity index?heart structure,cardiac contraction?.5.The limiting factors for aerobic capacity of youth athletes in different events are different,and the oxygen transport capacity?systolic and diastolic capacity?is the main factor for the difference in VO₂peak of youth athletes in different sports.The main limiting factors of VO₂peak for youth athletes in aerobic spotts are oxygen uptake capacity index?lung function?,oxygen transport capacity index?heart structure,cardiac contraction,cardiac relaxation?and oxygen utilization capacity index?tHb,SmO₂?,while the main limiting factors of VO₂peak for youth athletes in mixed oxygen events are oxygen uptake capacity index?lung function?,oxygen transport capacity index?heart structure?and oxygen utilization capacity index?tHb?.