To HIT program will be use cycle ergometers adapted for children (OXFORDTM, model BE2601, OXOFORD Inc, Santiago, Chile) were used. Each participant performed a range of 8 to 14 cycling intervals during the intervention period. The time of each work interval cycling will be increased progressively weekly, and ranged between 40-60 s (40 s weeks 1-2; 50 s weeks 3-5; 60 s week 6), with 120 s of passive rest (over the bicycle without movement) between each interval of work.

The RT will consist in voluntary concentric/eccentric exercise during 1 minute until to get a high subjective effort perception (i.e., between 8-10 points based on the modified and subjective Borg scale of 1 to 10 points. Subjects will perform 4 exercises (biceps curl, leg-extension, shoulders press, and upper row exercise) during 6-weeks.

We will compare within each group (G)-1, G-2, and G-3 sub-group according to both RT and HIT intervention both pre-post changes as well as if are there some anthropometric, cardiovascular, and performance variable predicting changes in homeostasis model assessment (HOMA-IR).

Exercise will be performed at three sessions per week. Post statistical analyses will be including analyses by the 3 sub-groups proposed. All sessions will be supervised by an exercise physiologist during 6 weeks.