What does means isometric exercise?

Advice by professor V.V.Matova.
And to fight osteochondrosis you need to do a physic exercises,but this is not a possible,if you are time is poor, and what you can to do? Isometric gymnastic this is for you, you can to do her and in a dental chair.  And isometry is muscles shortening,and by Crete means is muscles shortening without a changing her size. Muscle loading ,but not stretching. That system had formed from a frog, which a researches had pressed one leg, and in a few time, they had found ,that leg is non proportionally developed,and try to referee,she loaded muscles,and trained theirs.
Muscles training having an especially place in our life, they support skeleton, and gives a right position  and vital activity for organs,and they having metabolism processes ,that capillaries conditions for covering in muscles, will improve,that a good influences for organism.A doing of exercises you need to add a forces,patience and motivation, calm breathing,and every exercise doing till 6 seconds, do not fast train,and with pushes, load muscles,and a penetrate for support is a strong,that to avoid any transferring.