Hi all,
I was wondering if you guys feel like cardio hurts muscle growth. I am doing about 15 minutes of high intensity cardio exercise 4-5 times a week. Will this make it harder to put on muscle mass? I know running 10 miles a day might, but maybe in small amounts it wouldn't? I want to get to a lower body fat while putting on muscle mass so I've introduced some cardio. Thanks!
Hey Matt. First of all cardio doesn't necessarily kill muscle and it doesn't necessarily kill fat. Cardio are basically exercises that burn calories used to "supplement" a stable fat loss nutrition. You probably know to lose fat you need to be in a caloric deficit (process known as cutting, eat less calories so you can use your fat calories), and to gain muscle you have to be in a caloric surplus [bulking, eat more so the energy goes to the muscles] (or if you're already mid-fat to very fat (anything higher than 15%) you could be in a caloric deficit with a positive nitrogen balance and produce kinda slow muscle growth which is why 90% of people prefer caloric surplus for faster results). I don't know your current body fat [%] but if you are ectomorph or mesomorph which is fairly lean or lean, I'd just focus on a bulk.. In this case with all that cardio you'd have to compensate the calories you burn from cardio - which is easier to skip the cardio or have it 2-3 times a week (which is what people prefer for HIIT anyway). So to answer the question: Cardio doesn't burn muscles, it helps show them, what will burn muscles is a very big caloric deficit & the main thing - not eating enough protein. So look at your body and see if you'd be better off going on a cut or on a bulk (if you can see your muscles quite goodly defined, in example less than 15% body fat, preferably around the 11-14% range, just focus on bulking).
Daniel Malo
I am not quite sure how to tell, but I believe I am at about 15%. I am lean but not lean enough to see much abs until they are much bigger (although they are slowly starting to show through). I am at a comfortable level at which without doing cardio I don't think my body will change. Is it possible to do cardio and eat more calories and then when I'm not eating, my metabolism would be sped up and burn fat even though I ate enough protein to keep growing muscles? Thank you! By the way, what is the positive nitrogen balance? (Sorry for so many questions!)
First of all, great answer by Gligor, couldn't have said it better. You don't really need to be in a colonic deficit based on your definition of body-type. I'd reccomend training your abs around 3-4 times a week and eating cleaner. Cardio doesn't hurt muscle growth, like Gligor said, it all depends on your caloric intake. If you eat 3300 calories a day and burn 300 calories thanks to cardio, then you'll still gain mass cause you're eating 3000 calories(this is an example/estimate). But if you say "Oh, I'll eat 3000 calories today.", and do cardio(-300) then you're only really consuming 2700 calories a day, which will slow down your muscle growth(again, just an estimate). So no, you can gain size and do cardio. Just make sure you eat up the calories that you burned up!
Daniel Malo