Yep. I've done it, so have thousands over others using my program. But the best way to prove it is to try it yourself.
There are plenty of free Isometrics on my site - and a complete free guide with loads of exercises and workouts here - https://samuraistrengthtraining.com/starting-isometrics-the-ultimate-guide/
Download that, for free. Commit to training for 7 weeks doing the workouts in that. Do the work, make the commitment, get the results. ;-) Then if you want even better results, you can pick u my Perfect Body course.