I'm 19, 5-9, 190, 15%bf, i'm just trying to get down to about 7 or 8% bf so that i can try to compete for the first time, i want to know if i'im doing too much cardio or the wrong kind. 4 or 5 times a week i'll hit the treadmill and do HIT. 2 min. walk and 1 min run at about 12degrees slope total of 40 min. or so. is this too much cardio? will it result in muslce loss? should i just walk instead?