Using a bar forces both sides of the body to work together.
Due to the wide grip used in a squat, If the right side is working harder than the left, the bar will tilt you to the left. You will then have to shift your feet, work harder with the left and less with the right until.
We are never fully balanced. Even when standing, if we stopped using our balance for a moment our muscles would not know what to do and we would fall. By using a bar you are not only getting stronger but you are improving your ability to balance under great stress. This is why it is important for sports persons to use a bar.
Agreed. -And if using dumbbells, the effect is magnified due to more balance being required in more places. Hence, more functional strength over all because the body can better balance the weight utilizing MORE muscles rather than fewer from a bar centered in a spinal region.
If one was using the 180 lb dumbbells for instance, the amount of strength required forces all of the muscles in play to be used to handling 180 per side to hold weight in position which is closer to the outside of the body. A line of force goes straight down.
If one used a 360 lb barbell, the line of force goes straight down ONLY UNTIL off balance. In other words, the line of force going down the body is oriented and centered in the spine. It is a "capital 't' " if you will, whereas the dumbbells are 2 side-by-side "capital letter 'I' " formations.
End result: The body ends up better able to handle the weight in normal functional activity by dumbbells because you never lift things day-to-day with them on your spine, you do it with things in your HANDS.
Sure, its always good to mix it up, but never use dumbbells all the time.
Hawk – I’m not sure why you think that using a bar will give you a squat disproportionate with regions of the back or arms.
I guess I was not very clear.
When a heavy squat and a heavy overhead press, for example, are employed, which is heavier?
Typically the squat is heavier. The legs become able to handle "x" weight while the upper body "x divided by 2" for example. In this formula, assume that the person is doing ALL upper body movements at x divided by 2. (we all know that this is way stronger than practical, but it works for this example).
When the body is required to perform daily tasks, how do the arms properly support a natrual movement to lift when the legs do the lifting?
If a lift in daily tasks requires "x" force, when the upper body can only support "x divided by 2", you have weak points. Biceps tear or the spine takes too much load.
The bottom line is that 1/2 of your leg strength is hazzardous to employ in regular activity. If your upper body strength matched the lower body, you would easier handle any employment of your strength, and do it without the weak points. Hence, a far more effective strength factor in daily activities.
I think many times we get used to thinking in regular life: "I lifted this much in the gym, how can I do this now that I am not there with a bar?"
The natural thing should be: "I lift this every day, how can I SIMULATE THIS IN THE GYM."
We have our thinking exactly opposite from correct if we want to employ our strength.
Sorry to have derailed this, I merely wanted to add clarity to dumbbells and their role in efficient use of functional strength. I thought that would better make for an intellegent decision for when to use the bar and when not to.