One of the best ways to significantly increase the amount of pressure or depth that you can give your partner without having to put undue stress on your body are going to "Hulk Mode" is to use your feet to give your partner the massage. There are a lot of different styles of barefoot massage. The main differences in the styles are due to their origins and/or attempts to systematize the work or make it more proprietary. I am going to use the generic name "barefoot massage" as much as possible here and hope that does not offend any practitioners.
There are a lot of caveats and nuances here, but the main ones I will focus on are
These first three videos are pretty good instructional videos from PsycheTruth.
This video is a good example of some of the deeper work that you can do with your feet.
These next videos are just really great examples of how amazing barefoot massage can actually be. Enjoy...
Because you will never know if you don't try :-)