How to use long length partials 

Thank You, "Science Based Fitness". You expertly dispensed much needed information. On some resistance exercise movements, many trainers were unsure of exactly where the Lengthened part of the exercise Was! Thanks to You, that confusion has been cleared away. Kudos to You!

Thanks for the screenshot. Triceps was my biggest problem, was not sure should it be fully bent or fully extended. Rest of the muscles I could feel and knew already.

Sorry, but this is wrong You might show activation on your machine but it's like when a machine shows activation on a plank. Planks are worthless to build size and strength, all they do is make you better at doing planks but the machine shows activation everywhere that's exactly the same for partials. To build and strengthen a muscle you have to contract it and lengthen it and the less you lengthen it the less size and strength you're building, simple as that. You've had no response on this video because anybody that has ever worked out in any form knows Full ROM is better, your thumbnail killed you on this video. Sorry, man I'm getting beliefs straight from Science and Biomechanics