This is my third attempt with weight training, and at 10 months, my longest attempt so far. And I'm glad of the progress I have made this time: I certainly don't feel like a beginner any more - I can talk the gobbledygook of GH and leptin levels, and the differences between a stiff-legged deadlift and a Romanian deadlift :) But I'm also not an expert - there have been plenty of occasions where I have overtrained, and experienced soreness for days.
The typical beginner (and I could count myself as one when I started) encounters many problems when starting out with bodybuilding - there isn't adequate time to devote to the activity, form is always an issue, minor injuries keep occurring, the list goes on and on. Beyond these, an issue that pops up is that one's support structure (friends, family, etc.) is not always supportive of an individual's weight training. Even my doctor said, "You don't need weight training, cardiovascular endurance should be more than adequate." Another common comment I keep hearing is "Walking should be enough. It's the best exercise!"
Walking is the best exercise - Really? Best for what? Can one set a goal saying "I'll walk till the strength in my shoulders improves"? How does walking help improve the flexibility of the neck?
I'm not trying to make fun of walkers or cardiovascular exercises. In fact, I enjoy both running and cycling - I don't run very regularly, but I love doing a 25 klick cycle ride as often as I can. But doing a cardiovascular activity in isolation can do the body a lot more harm than good. Let me elaborate:
- Running long distances hurts the knees [google for the phrase "joggers' knee" - it will flood your browser with a zillion results] - Seasoned runners know they have to complement their running with specific exercises for the glutes, hamstrings, and the back, in addition to the pre-run stretches
- Cycling is a great exercise, but can take a toll on the back. It's unnatural for the body to be crouched down for long periods, and this leads to muscle fatigue. Ultracycling.com lays out some resistance training tips for cyclists (and swimmers). Even Lance Armstrong's training program mentions a few points on weight training - I would assume this includes hyperextension exercises for the back.
Now, walking may not be as intensive as running or cycling, so the wear & tear takes longer to appear, but as I sarcastically mentioned earlier, it can not help the body parts that it doesn't work out: walking can not help improve upper body strength and flexibility.
So, here's my opinion: it helps the body more if a cardiovascular activity is done as part of a more comprehensive fitness program that ensures:
- Coverage of as many muscle groups as possible
- Increase in strength of muscles and joints
- Increase in flexibility of the overall body
- Endurance [the cardio will probably take care of that]
Now, body building isn't the only option to meet the above criteria. Other options include calisthenics, yoga, and pilates, to name a few. So, pick one, and give your body the full-fledged fitness regimen it deserves. And please don't let others brainwash you by saying, "Exercise X is the best exercise."