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Updated: May 17, 2026

A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement
Published on: February 22, 2022
[Effect of an 8-week aerobic training program during physical education lessons on aerobic fitness in adolescents]
J Ramírez Lechuga1, J J Muros Molina, J Morente Sánchez
1Department of Sport and Informatics, University Pablo de Olavide, Seville, Spain.
Objective:
To determine the effect of a high intensity aerobic training program of 8 weeks, developed during physical education classes, on the aerobic capacity of adolescents aged 15 to 18 years.
Methods:
A total of 84 adolescents (51 boys and 33 girls) participated in this study. The aerobic capacity (VO(2)max) was measured directly with a portable gas analyzer (K4b², Cosmed) during the performance of the 20 Meters Shuttle Run Test (20mSRT). The sample was divided into 2 experimental groups (G2S and G3S) and 1 control group. The training program was composed of aerobic physical activity (75-80% VO(2)max.). The G2S developed 2 sessions per week while the G3S made 3.
Results:
The G2S increased VO(2)max (boys: from 55.7 to 56.6 ml/kg/min; girls: from 37.8 to 38.7 ml/kg/min; p < 0.001) and the number of stages in the 20mSRT (9.0% boys, p < 0.001; 20.0% girls, p < 0.001). The G3S also increased VO(2)max (boys: from 54.9 to 56.0 ml/kg/min; girls: from 36.0 to 38.7 ml/kg/min) and the number stages in the 20mSRT (10.4% boys, p < 0.001; 32.3% girls, p < 0.001). In G2S and G3s, girls showed greater improvement than boys.
Conclusions:
A high intensity aerobic training program developed during 8 weeks, 2 sessions per week, improves aerobic capacity of the students. An extra session of intense exercise for week is a greater improvement in girls, but do not produce such effects in boys.
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