Is it possible to lower body fat while using long acting insulin? My plan is to use it while on steroid cycle. And protocol would be - 1 hour fasted cardio in the morning and then after a few hours I'd inject 20iu's of long acting insulin (lantus). So basically I'd burn fat in the morning and build muscle later in the day.. Because as we know, it's impossible to burn fat while there is insulin in your body.