Originally posted by deepsoup
If thats the case, isn't there a danger you might be teaching yourself to be tense throughout your techinque? (Like trying to maintain an 'unbendable arm' with your biceps fighting against your triceps.) Sounds like it might be a bad idea.
Originally I also thought the same thing, and I was reluctant to try the exercise after my uncle showed it to me. When I tried the exercise for 15 minutes I was covered in sweat and my muscles were so tired they became oppose to flexing and are were quite relaxed. Right after dynamic tension exercises I practiced shadow boxing and combination drills. The muscles are so relaxed after dynamic tension exercises that your strikes fly out like a whip. The only real problem I encountered is that I would inadvertently strike my lead punch before I could pull it back with my follow through punch of the other hand. The difference in speed is so different that you have to readjust your timing.
So maybe I should clarify if you are trying dynamic tension exercise. First perform the dynamic tension exercise for as long as you like, but make sure to produce a good sweat and tire the muscles out slightly. Next, perform shadow boxing drills and combination drills for at least an equal length of time. I feel the two in conjunction will counteract any conditioning by the body to become tense during the execution of an actual technique.
But like I said earlier, I prefer the tai chi chuan extension method better for aikido.
Peace and Blessings.