I dont understand marinera: what does “do a dip with a very narrow gip” mean?
Pulling with an equivalent force of you bodyweight? That sounds like crazy. I don’t think one can stretch over 15-20 kilos force SD. And no more than 15kilos holding the stretch confortably for 1-2 min. I will try tonight how much maximun weight I can hold SD and SD/BTC(sitting).
Would be great to know from other people here