[stu3ufc]

i have gone with and without-- i currently run to music-- and far more enjoy my running with music, its just more fun and can put u in a better state

if you want good concentration and mental toughness --really go without-- but u gotta be in ur own head --telling urself to run faster, harder, longer

music blocks out those crappy thoughts of "oh lets stop" "im bored, i cant be bothered lets cut it short"

i cud never lift weights without music tho--one day i forgot my music and the radio was broken --so the gym was silent except for grunts and groans---