Have you tried using a stick or broom handle to do your isometric exercises? Using a tool like this can add another dimension to your routine. You can use a stick by simply holding it in your hands and pushing and pulling with it in front of you, behind you and over your head. You should hold each movement for at least 7 seconds.
Vary the distance between your hands from close together to far apart to hit the muscles at different angles because you want to exercise the muscles in more than one position. Try placing one end of the stick on the ground in front of you and pushing down on it with both hands or use each hand separately, this will target your back and your abs. Push down with one arm and feel your Lat muscle with the other hand, you will notice how it is tensed up.
There are many ways you can do isometric exercises like this. Hold the stick over your head with your two hands holding it. Push your hands together while squeezing the stick then try pulling outwards on the stick. Pushing will target your shoulders and pulling will target your Lats. Try using the stick from every position you can think of and vary how close or far apart your hands are and you will get a good workout.
Isometrics are great because you can do them anywhere with little or no equipment. You can do them alone or use them together with weights or bodyweight exercises.
Isometric Exercises Done With a Stick by Tim Archbold