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Cardio Debate/Question

Just last night I was sitting with one of my friends and we started talking about working out. I haven’t known her very long but I did know that she worked out and ran a lot (5-8 mile sessions).

Somehow we got to talking about training legs and she proceeded to state that running was great for building leg muscles…needless to say I almost fell out of my chair and got very excited at the chance to help out her poor misinformed soul.

She was adamant that if I wanted big legs I needed to run and that she herself has gained consider muscle in her legs from running (and she does have a descent amount of leg muscle).

Now as I began telling her that running for muscle building couldn’t hold a candle to squats, lunges, leg-presses, and stiff-leg deadlifts, I got a little overworked and said that running wouldn’t build muscle at all.

In hindsight I bet that was probably an inaccurate statement but as I continued to ponder this question I realized I didn’t have any solid information about running and it’s direct muscle-building properties.

It seems evident that it really would be a second tier form of leg building, as I don’t think a typical bodybuilders leg day consists of 5 miles on the track but my question is does anyone have any evidence or can point to any studies that show anything about the correlation between running and gaining leg muscle?

Everything I know about running is mainly for fat burning, pure cardiovascular health, and the secondary benefits cardio gives you for muscle building (can eliminate c02 better, flush lactic acids, etc.)

I realize there are lots of individual variables that could affect whether one gains muscle simply from running, such as genetics but any help with this question would be appreciated!

Thanks T-People!

well running for middle distances might increase leg muscle if you are already under a certain muscle size level. Usually though the body will try to lose as much weight as possible when doing long distance cardio activity, thus this will cause fast muscle loss. laters pk

My legs got huge after i got out of the Marines. I rarely did legs and ran about 35-40 miles a week. Also considering that i think i was constantly eating above caloric intake and slowly gaining muscle in a span of about 2 1/2 years.

It all depends on the individual. I know many people who gain the most hypertrophy on any bodypart, with higher than usual recommended rep range. Ian King has talked about this in one of his videos I recently saw. Some people actually gain muscle with rep ranges in the 20-100 REP RANGE!! Sounds crazy, but it is all based on the individual. Also remember that if you have been following a low rep range for a long while, the shock of high reps will induce the body to adapt to the extra workload and that might mean an increase in size. So you can increase muscle in the legs by running, especially if you add intervals or periods of high power output. I train at the York University Track Centre in Toronto, home to Charlie Francis and some of the world’s greatest sprinters past and present and you would not believe the leg development on these athletes. I watch them train and it amazes me how little actual strength training with weights they do. Most of the “strength” work they do is running.

You’re right, she’s wrong. When is the last time you saw a runner with big (or ripped, for that matter) legs?

Mind you, I’m talking T-Mag big, not everyday person ‘big’. Females can, I believe, develope shapely and/or ‘tone’ (I cringe to use that word) legs, but a man’s legs developed from running don’t look like much. Mind you, I’m talking about running/jogging, not sprinting.

I’m sure that people with a high percentage of slow-twitch fibers can gain muscle size by doing long-distance running. I’ve known a few female cross-country runners who put on quite a bit of leg muscle through running (and eating.)

Type 1 muscle fibers will hypertrophy under aerobic conditions. They just don’t have the potential for growth that the type 2 fibers do. It is genetic as to how much you will gain, based on your fiber type ratio. A good way to tell if you would hypertrophy well on an aerobic program would be to test a higher rep range of a conventional lift (squats) against your max. If you can get >75% of your max for 12 reps or so, chances are you are very type 1 dense, and thus would hypertrophy on aerobic training significantly more than someone with more type 2 fibers.

I would imagine it depends on intensity and duration. When I ran long distances, my legs looked muscular, but were absolutely tiny little sticks. When I started running short little bursts up hills and stairs to improve my shotput performance, my quads blew up practically overnight. I believe Mike Mentzer used to draw comparisons to the physiques of distance runners vs. sprinters in a similar manner.

Those we consider “runners” who train over long distances often find themselves in calorie deficit which reverses muscle growth. Additionally, while they’re training they’re also canibalizing their muscle mass by using their muscle for fuel. Thus the debate on this forum about whether to do any running at all.

I would say that she was (partly) right, but it changes from person to person. For example, a few years ago I did not do any leg exercises at the gym. But - I cycled frequently, anything from 10 to 20 kilometers (approx. 6 - 13 mails) a day with longer trips during summer weekends. I had big quads. By big, I don’t quite mean T-mag “big”, but a lot bigger than people usually have, and big even compared to other body parts that I trained at the gym (there was a fair bit of fat as well, though). I don’t see why this wouldn’t apply to running as well. But you don’t need running to build big legs, just that it is possible.

I know that I am destined to have big legs - they respond very well now that I have began squatting, and my family is of the type “long back, short and stocky feet”. Of course, with direct hypertrophy work they grow much better than with just cycling.

lets not be too narrow minded here…as with any exercise, the physiological response depends upon the loading parameters. If you’re interesting in gaining muscle mass on the legs from running, and you are of average fiber distribution (ie. not an elite athlete at one end of the spectrum) sprinting should serve to add a substantial amount of muscle mass to your legs. As for the correlation between running and leg muscle, just look at any sprinting event there is, the guys have AMAZING leg development for their stature.