att : see other review for ppl who have use this a while . its not a gym replacement . but its something to get a good pump say before you go out . I have be work out 5 to 10 time a week consistently for the past year and a half -lrb- some two a day -rrb- . and I would not believe it my self have I be read this without ever try it . also note that I work out with high intensity and focus completely on that . not talk to ppl or waste time . well , I be over at a friend house the other day and he have one of these funny look thing . I shake it for a while and feel a good pump . the next day my biceps be hurt and that just do not happen often . I think I have get all the lactic acid out long ago , but this thing get what be leave . I be get one . so be this a one stop shop for any real fitness goal ? NO. . be good to have ? yes . why ? because it give you diversity in you workout and it be CHEAP . Lactic Acid - release by you muscle when stressed . the reason for the muscle soreness day after start a workout routine .