Hi Susanne, i looked up the study you may be referring to. While I don't have hypertension (yet) I have a very strong family hx of it so I found it interesting. Thanks for bringing it to my attention as I'll try to incorporate more isometric work now.
I don't recall any specific Cathe workout that "features" iso-holds, she does have workouts where she incorporates them:
Wall sits: Xtrain Legs (they squat with movement but you could just hold it), STS2 LB2 workout (near the end) - the crew actually squat with movement but Cathe does not. LIS Tri-sets has a set of wall squats too at the beginning. Again, you could just do the hold. Wall-sits could be substituted anytime Cathe does squats.
Planks: Cathe often does planks but usually incorporates movement to make them harder; you could just sub stationary. I add stationary planks (on elbows due to arthritis) to a workout myself by supersetting them with another core exercise.
Iso-hand grips: Cathe uses these in STS2 sometimes in unilateral moves. Like a bicep curl will have an iso-hold for one arm while the other curls or in a shoulder press. The STS2 Giant Sets Unilateral round may give you more ideas.
