Standing on one leg is an easiest way to develop your balance
We don’t think much about it, but walking and even just standing straight require lots of physical training. Robotic scientists are working hard to simulate stability in the human body, but so far cannot recreate it perfectly. Most of us needed a couple of years to learn how to run without tumbling every five seconds! We are lucky that we went through this training period when we were really young.
It is not the heavy weight, but the level of muscle fatigue is the most important factor to get great muscle toning. You can use a light weight but you need to lift it until you cannot lift it anymore.
A half of female office workers report frequent neck pain. One cause of this problem is their posture. One study published in Denmark says that easy weight training for women can improve this condition.