I have a few simple queries here. First of all, if a person does some weight training for a some time( say a couple of months) and then stops doing it, will his body shape become worse than what he started with? does that mean he has to work out forever once started?
Also i started lifting a few weights and i could sense a change in all my body muscles not just biceps. Is it just beginners luck or lifting weights gives the entire body a good workout and you don't have to do all the different types of drills and exercises?
As far as the first part, I have no real clue. I do know you cant get to a point that you like and just stop training / lifting. You wont maintain it without keeping up an exercise routine, but I wont say you'd be worse then what you started with unless you fell back into the same old bad routine.
As far as the 2nd part, I'm sure it has more to do with you probably havent used those muscles so ANYTHING that stimulated them would allow you to feel them working. Same thing if you would go out and do yard work after not doing any all winter. That bending and lifting and stretching etc etc weeding / cleaning up sticks / limbs even if not heavy would make you sore the next day if you werent used to it.
when you stop working out, the research shows that you can start to lose muscle mass anywhere from 2-5 weeks after you stop. Even worse sometimes you start to build up fat again and the muscles get "hidden away" quickly. There is a very simple rule that applies to your muscles, your joints, and your brain- use it or lose it baby! Sorry but its one of the fundamental laws of thermodyamics - if you don't add energy to something it will fall apart.
Having said that your body shape won't be worse than when you started assuming that you are basically returning to the same level of effort as when you started.
Question 2: Its nearly impossible to isolate a muscle 100% (so that you are only exercising that one muscle). When you do something like benchpress you are using chest, shoulders, triceps, even your back. So even if you do a "bicep" exercise there is typically collaterate benefits particularly in the forearms and shoulders. Frankly that's a good thing. Your core body gets exercised with weight lifting and makes your entire body strong.
What johnj7777 said is correct, BUT I want to answer your question directly. You will NOT end up in worse shape than you started with if you stop the training, assuming you go back to doing things exactly as before. In fact, it will make it easier to get back to the point you left off once you start weight training again.
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