Im running right now t3(about 2weeks total now) at 75 mcg with 2cc of t400.The last 3-4 days i dont feel very well at all during workout.Seems like my cardio is not there anymore plus my heart rate is alot faster.Im out of breath alot and i feel like im going to collapse.Do you guys think its t3.........and by the way its my first time using t3 and ive done 3 steroid cycle im 6ft0 220 lbs at 9 %bf.....anyway thks