try pushing slower also when injecting. i use to get bruises to from subcutaneous anything. insulin,igf hgh, it came down to injecting slower.
some guys bruise sometimes and sometimes they dont, but i think everyone does from time to time, in terms of the igf-1 lr3 as long as you are using muscle chemistry with acetic acid then at least you know it cant be from infection or bacteria or anything like that cause acetic acid would kill it on contact, if you are using some other version with water then becareful cause water breeds bacteria easily.
i have used igf here for a while and no problems but sometimes a i will get a little knot if i push it out to fast or dont go in deep enough.