My name is David. I´m from Germany and I´m currently living in Innsbruck, Austria. I´ve found this great forum while doing some researches on the lightweight dumbbel system. I´m generally enjoying bodyweight training since several years. Currently I´m working on my pull up strength (with extra weights) and I´m also working on my strength to perform a proper handstand push up.
Some weeks ago, I found something totally new to me (although quite old right now

There are certain points however that I don´t completely understand. According to Eugen Sandow, the number of repetitions must be increased gradually by a given amount, Attila however is very vague about it and recommends 50 to 100, or 20 to 30 reps for example, depending on the exercise.
So should the number of reps be really increased over time? On the one hand I think that the endurance will increase. But on the other hand I think that someone who is very experienced with these exercises can flex his/her muscles very much, so the muscles are exhausted quicklier.
How exactely should I flex the muscles used? When doing bicep curls for example, I´m not sure whether I should flex my biceps and triceps simultaneously or not. Sandow just wrote that both muscles are used for this exercise. He adviced to "make tense the muscles of your arms...". About the muscles used he wrote: "This exercise will develop chiefly the flexor biceps muscle,and the triceps extensor muscle, of the upper arm". So should I flex the opponent muscles simultaneously to create the necessary tension for each exercise or should other muscles be flexed during the concentric and eccentric part of the movement?
I´m very much looking forward to your answers!
Thank you in advance!
Best regards,
David